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Service Manual 



Tektronix 

/ 



1502B 

Metallic Time-Domain Reflectometer 
070-6267-04 



This document applies for firmware version 5.02 
and above. 

Warning 

The servicing instructions are for use by qualified 
personnel only. To avoid personal injury, do not 
perform any servicing unless you are qualified to do 
so. Refertothe Safety Summary prior to performing 
service. 



First Printing: June 1996 
Revised: February 1998 



Instrument Serial Numbers 



Each instrument manufactured by Tektronix has a serial number on a panel insert or tag, or stamped on the 
chassis. The first letter in the serial number designates the country of manufacture. The last five digits of the 
serial number are assigned sequentially and are unique to each instrument. Those manufactured in the 
United States of America have six unique digits. The country of manufacture is identified as follows: 

B010000 Tektronix, Inc., Beaverton, Oregon, U.S.A. 

E200000 Tektronix United Kingdom, Ltd., London, England 
J300000 Sony/Tektronix, Japan 

H700000 Tektronix Holland, NV, Heerenveen, The Netherlands 

Instruments manufactured for Tektronix by external vendors outside the United States are assigned a 
two-digit alpha code to identify the country of manufacture (e.g., JP for Japan, HL for Honk Kong, IL for 
Israel, etc.). 

Tektronix, Inc., RO. Box 500, Beaverton, Oregon 97077, USA 
Printed in U.S.A. 

Copyright Tektronix, Inc., 1998. All rights reserved. Tektronix products are covered by U.S. and foreign 
patents, issued and pending. TEKTRONIX and TEK are registered trademarks of Tektronix, Inc. 



FCC Class A Device 

This equipment has been tested and found to comply with the limits for a 
Class A digital device, pursuant to Part 15 of the FCC Rules. These limits are 
designed to provide reasonable protection against harmful interference in a 
commercial environment. This equipment generated, uses, and can radiate 
radio frequency energy, and, if not installed and used in accordance with the 
instructions, may cause harmful interference to radio communications. Op- 
eration of this equipment in a residential area is likely to cause harmful interfer- 
ence, in which case the user will be required to correct the interference at his 
own expense. 

Changes or modification not expressly approved by Tektronix can affect 
emission compliance, and could void the user’s authority to operate this 
equipment. 



The 1502B Metallic Time-Domain Reflectometer was designed and manufactured by: 

Tektronix, Inc. 

100 S.E. Wilson Ave. 

Bend, Oregon 97702 U.S.A 
Phone: 1-800-835-9433 



Certificate of the Manufacturer/Importer 

We hereby certify that the Tektronix 1502B Metallic TDR complies with the RF 
Interference Suppression requirements of Amtsbl.-Vfg 1046/1984. The German 
Postal Service was notified that the equipment is being marketed. The German 
Postal Service has the right to re-test the series and to verify that it complies. 

TEKTRONIX 

Bescheinigung des Herstellers/lmporteurs 

Hiermit wird bescheinigt, dap das Tektronix 1 502B Metallic TDR Ubereinstimmung 
mit den Bertimmungen der Amtsblatt-Verfugung 1046/1984 funkentstort ist. Der 
Deutschen Bundespost wurde das Inverkehrbringen dieses Gerates angezeigt 
und die Bereschtigung zur Uberprufung der Serie auf Einhalten der 
Bestimmungen eingeraumt. 

TEKTRONIX 



NOTICE to the user/operator: 

The German Postal Service requires that this equipment, when used in a test setup, 
may only be operated if the requirements of Postal Regulation, Vfg. 1046/1984, Par. 
2, Sect. 1 .7.1 are complied with. 

HINWEIS fur den Benutzer/Betriber: 

Dieses Gerat darf in Mepaufbauten nur betrieben werden, wenn die 
Voraussetzungen des Par. 2, Ziff. 1.7.1 der Vfg. 1046/1984 eingehalten werden. 



NOTICE to the user/operator: 

The German Postal Service requires that systems assembled by the operator/user 
of this instrument must also comply with Postal Regulation, Vfg. 243/1 991 , Par. 2, 
Sect. 1 . 

HINWEIS fur den Benutzer/Betreiber: 

Die vom Betreiber zusammengestellte Anlage, innerhalb derer dieses Gerat 
eingesetzt wird, mu8 ebenfalls den Voraussetzungen nach Par. 2, Ziff. 1 der Vfg. 
243/1991 , genugen. 



WARRANTY 



Tektronix warrants that this product will be free from defects in materials and workmanship for a 
period of one (1) year from the date of shipment. If any such product proves defective during this 
warranty period, Tektronix, at its option, either will repair the defective product without charge for 
parts and labor, or will provide a replacement in exchange for the defective product. 

In order to obtain service under this warranty, Customer must notify Tektronix of the defect before the 
expiration of the warranty period and make suitable arrangements for the performance of service. 
Customer shall be responsible for packaging and shipping the defective product to the service 
center designated by Tektronix, with shipping charges prepaid. Tektronix shall pay for the return of 
the product to Customer if the shipment is to a location within the country in which the Tektronix 
service center is located. Customer shall be responsible for paying all shipping charges, duties, 
taxes, and any other charges for products returned to any other locations. 

This warranty shall not apply to any defect, failure or damage caused by improper use or improper or 
inadequate maintenance and care. Tektronix shall not be obligated to furnish service under this 
warranty a) to repair damage resulting from attempts by personnel other than Tektronix 
representatives to install, repair or service the product; b) to repair damage resulting from improper 
use or connection to incompatible equipment; or c) to service a product that has been modified or 
integrated with other products when the effect of such modification or integration increases the time 
or difficulty of servicing the product. 

THIS WARRANTY IS GIVEN BY TEKTRONIX WITH RESPECT TO THIS PRODUCT IN LIEU OF 
ANY OTHER WARRANTIES, EXPRESSED OR IMPLIED. TEKTRONIX AND ITS VENDORS 
DISCLAIM ANY IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A 
PARTICULAR PURPOSE. TEKTRONIX’ RESPONSIBILITY TO REPAIR OR REPLACE 
DEFECTIVE PRODUCTS IS THE SOLE AND EXCLUSIVE REMEDY PROVIDED TO THE 
CUSTOMER FOR BREACH OF THIS WARRANTY. TEKTRONIX AND ITS VENDORS WILL NOT 
BE LIABLE FOR ANY INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES 
IRRESPECTIVE OF WHETHER TEKTRONIX OR THE VENDOR HAS ADVANCE NOTICE OFTHE 
POSSIBILITY OF SUCH DAMAGES. 



Table of Contents 



List of Figures iii 

List of Tables viii 

General Safety Summary ix 

Service Safety Summary xi 

General Information xiii 

Installation and Repacking xiv 

Operating Instructions 1-1 

Overview 1-1 

Preparing to Use the 1502B 1-4 

Display 1-5 

Front-Panel Controls 1-5 

Menu Selections 1-7 

Test Preparations 1-10 

Cable Test Procedure 1-12 

Additional Features (Menu Selected) 1-25 

Operator Performance Checks 2-1 

Specifications 3-1 

Electrical Characteristics 3-1 

Environmental Characteristics 3-3 

Physical Characteristics 3-4 

Options and Accessories 4-1 

Option 03: Battery Pack 4-1 

Option 04: YT-1 Chart Recorder 4-1 

Option 05: Metric Default 4-1 

Option 07: YT-1S Chart Recorder 4-2 

Power Cord Options 4-2 

Accessories 4-2 

Circuit Descriptions 5-1 

Introduction 5-1 

Power Supply 5-4 

Processor System 5-7 

Option Port Interface 5-10 

Video Processor 5-13 

Timebase 5-15 

Elapsed Time Indicator (SN <B020511 only) 5-22 

Driver/Sampler 5-23 

Front Panel 5-25 

Display Module 5-29 



1502B MTDR Service Manual 




Contents 



Calibration 6-1 

Introduction 6-1 

Calibration Performance Check 6-1 

Display Module Check 6-2 

Front Panel Check 6-4 

Horizontal Scale (Timebase) Check 6-7 

Zero Offset Check 6-10 

Vertical Position (Offset) Check 6-12 

Noise Check 6-13 

Sampling Efficiency Check 6-15 

Offset/Gain Check 6-16 

RAM/ROM Check 6-16 

Aberrations Check 6-17 

Risetime Check 6-19 

Jitter Check 6-21 

Option 03: Battery Pack Check 6-23 

Option 04/07 : YT-l/YT- 1 S Chart Recorder Check 6-23 

Option 05: Metric Default Check 6-23 

Adjustment Procedures 6-24 

Visual Inspection 6-25 

Power Supply Checks and Adjustments 6-25 

Main Board ”12 VDC Check and Adjust 6-29 

Impedance Check 6-34 

LCD Check and Adjustment 6-35 

Zero Offset Adjust 6-38 

After Adjustments are Completed 6-40 

Maintenance 7-1 

Introduction 7-1 

Preventive Maintenance 7-1 

Part Removal and Replacement 7-2 

Troubleshooting 7-14 

Control Panel Installation 7-20 

Top and Bottom EMI Shield Installation 7-21 

Installing the Case Cover Over the Chassis 7-22 

Replaceable Electrical Parts 8-1 

Diagrams 9-1 

Replaceable Mechanical Parts 10-1 



ii 



1502B MTDR Service Manual 



Contents 



List of Figures 



Figure 1-1: Rear Panel Voltage Selector, Fuse, AC Receptacle 1-1 

Figure 1-2: Display Showing Low Battery Indication 1-3 

Figure 1-3: 1502B Front-Panel Controls 1-4 

Figure 1-4: Display and Indicators 1-5 

Figure 1-5: Vp Set at .30, Cursor Beyond Reflected Pulse 

(Set Too Low) 1-11 

Figure 1-6: Vp Set at .99, Cursor Less Than Reflected Pulse 

(Set Too High) 1-11 

Figure 1-7: Vp Set at .66, Cursor at Reflected Pulse (Set Correctly) 1-12 

Figure 1-8: 20-ft Cable at 5 ft/div 1-12 

Figure 1-9: Short in the Cable 1-13 

Figure 1-10: Open in the Cable 1-13 

Figure 1-11: 455-ft Cable 1-14 

Figure 1-12: 455-ft Cable 1-14 

Figure 1-13: Reflection Adjusted to One Division in Height 1-15 

Figure 1-14: Return Loss 1-16 

Figure 1-15: Ohms-at-Cursor 1-17 

Figure 1-16: Display with VIEW INPUT Turned Off 1-18 

Figure 1-17: Display of a Stored Waveform 1-18 

Figure 1-18: Display of a Stored Waveform 1-18 

Figure 1-19: Waveform Moved to Top Half of Display 1-19 

Figure 1-20: Current Waveform Centered, Stored Waveform Above . 1-20 

Figure 1-21: Current Waveform Center, Stored Waveform Above, 

Difference Below 1-20 

Figure 1-22: Waveform of Three-Foot Lead-in Cable 1-21 

Figure 1-23: Cursor Moved to End of Three-Foot Lead-in Cable .... 1-22 

Figure 1-24: Cursor Moved to End of Three-Foot Lead-in Cable .... 1-22 

Figure 1-25: Cursor Moved to 0.00 ft 1-23 

Figure 1-26: Incident Pulse at Three Divisions 1-23 

Figure 1-27: Waveform of Short 75 Q Cable 1-24 

Figure 1-28: Waveform Centered and Adjusted Vertically 1-24 

Figure 1-29: Cursor Moved to Desired Position 1-25 

Figure 1-30: Waveform Viewed in Normal Operation 1-26 

Figure 1-31: Waveform Showing Intermittent Changes 1-26 

Figure 1-32: Waveform Display with No Outgoing Pulses 1-27 

Figure 1-33: A Captured Single Sweep 1-28 

1502B MTDR Service Manual iii 



Contents 



Figure 2-1: Start-up Measurement Display 2-2 

Figure 2-2: Measurement Display with 3-foot Cable 2-2 

Figure 2-3: Cursor at End of 3 -foot Cable 2-3 

Figure 2-4: Flat-Line Display Out to 50,000+ Feet 2-3 

Figure 2-5: Flat-Line Display at -2.000 ft 2-4 

Figure 2-6: Waveform Off the Top of the Display 2-4 

Figure 2-7: Waveform at the Bottom of the Display 2-5 

Figure 2-8: Waveform with Gain at 5.00 mp/div 2-5 

Figure 2-9: Top of Pulse on Center Graticule 2-7 

Figure 2-10: Rising Edge of Incident Pulse in Left-most 

Major Division 2-7 

Figure 2-11: Waveform Centered, Cursor at 0.000 ft 2-8 

Figure 2-12: Pulse Centered on Display 2-8 

Figure 2-13: Cursor on Lowest Major Graticule that Rising Edge 

crosses 2-9 

Figure 2-14: Cursor on Highest Major Graticule that Rising Edge 

crosses 2-9 

Figure 2-15: Jitter Apparent on Leading Edge of Incident Pulse .... 2-10 

Figure 2-16: Jitter Captured Using Max Hold 2-10 

Figure 5-1: System Block Diagram 5-2 

Figure 5-2: Waveform Accumulation Diagram 5-3 

Figure 5-3: Power Supply Block Diagram 5-4 

Figure 5-4: Processor Block Diagram 5-8 

Figure 5-5: Option Port Interface Block Diagram 5-11 

Figure 5-6: Video Processor Block Diagram 5-13 

Figure 5-7: Video Processor Output 5-15 

Figure 5-8: Timebase Block Diagram 5-16 

Figure 5-9: Timebase Control 5-17 

Figure 5-10: Combined Effects of Time Delay 5-18 

Figure 5-11: Calibration of Delay Zero and 50-ns Analog Delay .... 5-19 

Figure 5-12: Driver/Sampler Block Diagram 5-24 

Figure 5-13: Front Panel Block Diagram 5-26 

Figure 5-14: Display Module Block Diagram 5-29 

Figure 5-15: SBE Cell 5-31 

Figure 5-16: Row Driver Block Diagram 5-31 

Figure 5-17: Column Driver Block Diagram 5-32 

Figure 5-18: Row Timing Diagram 5-34 

Figure 5-19: Column Timing Diagram 5-35 



iv 



1502B MTDR Service Manual 



Contents 



Figure 5-20: Shift Register 5-37 

Figure 5-21: CPU and Display Memory Interface 5-39 

Figure 6-1: Typical Start-Up Display 6-2 

Figure 6-2: Waveform on the Display 6-2 

Figure 6-3: Setup Menu 6-3 

Figure 6-4: Main Menu 6-4 

Figure 6-5: Diagnostics Menu 6-5 

Figure 6-6: Front Panel Diagnostic Display 6-5 

Figure 6-7: Front Panel Diagnostic Display 6-6 

Figure 6-8: Front Panel Diagnostic Display 6-6 

Figure 6-9: Front Panel Diagnostic Display 6-7 

Figure 6-10: Waveform on the Display with No Cable Attached .... 6-8 

Figure 6-11: Display with 3-ft Cable and Stored Waveform 6-8 

Figure 6-12: Cursor on Rising Edge of Pulse 6-9 

Figure 6-13: Cursor at 0.000 ft 6-9 

Figure 6-14: Cursor on Rising Edge of Pulse 6-9 

Figure 6-15: Flatline Display to >2,000 ft 6-10 

Figure 6-16: Incident Pulse at -2.000 ft 6-11 

Figure 6-17: Incident Pulse at -2.000 ft with 3-ft Cable Connected . . 6-11 

Figure 6-18: Incident Pulse at -2.000 ft with Max Hold 6-11 

Figure 6-19: Waveform at Top of the Display 6-12 

Figure 6-20: Waveform at Bottom of the Display 6-13 

Figure 6-21: Waveform at Centered 6-13 

Figure 6-22: Cursor Moved to 100.000 ft 6-14 

Figure 6-23: Noise with Gain at 5.00 mp 6-14 

Figure 6-24: Noise Diagnostic Display 6-15 

Figure 6-25: Service Diagnostic Menu 6-15 

Figure 6-26: Service Diagnostic Menu 6-16 

Figure 6-27: Service Diagnostic Menu 6-17 

Figure 6-28: Waveform with Cursor at -2.000 ft 6-18 

Figure 6-29: Waveform at 50 mp/div 6-18 

Figure 6-30: Waveform at 5 mp/div 6-19 

Figure 6-3 1 : Incident Pulse at Center of Display 6-19 

Figure 6-32: Incident Pulse Centered, Vertical Increased 6-20 

Figure 6-33: Cursor on Rising Edge at First Horizontal Graticule . . . 6-20 

Figure 6-34: Cursor on Rising Edge at Last Horizontal Graticule . . . 6-21 

Figure 6-35: Rising Edge at Center of Display 6-22 

Figure 6-36: Rising Edge with Scale at 1.0 mp/div 6-22 



1502B MTDR Service Manual 



v 



Contents 



Figure 6-37: Rising Edge with Max Hold on 6-22 

Figure 6-38: Head Alignment Chart Print 6-23 

Figure 6-39: Circuit Board Locations in the Instrument 6-24 

Figure 6-40: Power Supply Board 6-26 

Figure 6-41: Power Supply Test Points TP 1020 and TP 10 10 6-26 

Figure 6-42: Power Supply Test Point TP2030 6-27 

Figure 6-43: Connector Plug P5040 and Pins J5040 on Bottom of 

Main Board 6-28 

Figure 6-44: Power Supply Test Point TP 1020 6-28 

Figure 6-45: Power Supply Test Point TP2030 6-29 

Figure 6-46: Location of Main Board in Instrument 6-29 

Figure 6-47: Main Board Probe Points 6-30 

Figure 6-48: Waveform on Display 6-30 

Figure 6-49: Battery Pack Port Jacks on Frame 6-31 

Figure 6-50: CR20 12 on Power Supply Board 6-31 

Figure 6-51: Display Showing Power is Battery 6-32 

Figure 6-52: Display Showing Battery Voltage is Low 6-32 

Figure 6-53: R2012 on Power Supply Board 6-33 

Figure 6-54: Driver/Sampler Board Location 6-34 

Figure 6-55: TP 1030 on Driver/Sampler Board 6-34 

Figure 6-56: R1018 on Front Panel Board 6-35 

Figure 6-57: LCD Pattern with Contrast Too Light 6-35 

Figure 6-58: LCD Pattern with Contrast Too Dark 6-36 

Figure 6-59: LCD Pattern Adjusted for Sharpness 6-36 

Figure 6-60: Waveform with Contrast Too Light 6-37 

Figure 6-61: Waveform with Contrast Adjusted Correctly 6-37 

Figure 6-62: Driver/Sampler Board Location 6-38 

Figure 6-63: Incident Pulse at -2.000 ft 6-39 

Figure 6-64: R1042 on Driver/Sampler Board 6-39 

Figure 7-1 : Location of Voltage Selector and Fuse Holder on 

Rear Panel 7-2 

Figure 7-2: Desiccant Cartridge on Rear of Chassis 7-4 

Figure 7-3: Power Supply Module and P/O Rear Panel 7-5 

Figure 1 - 4 : DC (Battery) Banana Plugs 7-8 

Figure 7-5: Main Board 7-9 

Figure 7-6: Elapsed Time Indicator on Main Board 7-9 

Figure 7-7: EPROM on Main Board 7-10 

Figure 7-8: Lithium Battery on Main Board 7-10 



vi 



1502B MTDR Service Manual 



Contents 



Figure 7-9: Display Module/Front Panel Board Screw Locations . . . 7-12 

Figure 7-10: Display Module/Front Panel Board Showing Hex Nuts . 7-13 

Figure 7-1 1 : Location of Default Jumper on Front Panel Board 7-13 

Figure 7-12: Default Jumper Positions 7-14 

Figure 7-13: Main Board TP1041 and TP3040 7-15 

Figure 7-14: Main Board TP3041 and TP4040 7-15 

Figure 7-15: Main Board TP60 10 and TP70 10 7-16 

Figure 7-16: Main Board TP90 11 and TP9041 7-16 

Figure 7-17: Front Panel CABLE Connector 7-16 

Figure 7-18: Installing Top and Bottom EMI Shields 7-21 

Figure 7-19: Installing the Case Cover Over the Chassis 7-22 

Figure 9-1: Special Schematic Symbols 9-3 

Figure 9-2: Component Locator - Main Board 9-15 

Schematics - Main Board 9-16-24 

Figure 9-3: Component Locator - Front Panel Board 9-25 

Schematics - Front Panel 9-26-27 

Figure 9-4: Component Locator - Power Supply Board 9-28 

Schematics - Power Supply 9-29 

Figure 9-5: Component Locator - Driver/Sampler Board 9-30 

Schematics - Driver/Sampler 9-31 

Schematics - Power Fuse Jack 9-32 

Figure 10-1: Cabinet 10-17 

Figure 10-2: Frame, Assemblies and Front Panel Controls 10-18 

Figure 10-3: Power Supply 10-19 

Figure 10-4: Battery Pack 10-20 



1502B MTDR Service Manual vii 



Contents 



List of Tables 



Shipping Carton Test Strength xv 

Fuse / Voltage Ratings 1-2 

Vp of Various Dielectric Types 1-10 

Operator Performance Checks - Equipment Required 2-1 

Specifications: Electrical Characteristics 3-1 

Specifications: Environmental Characteristics 3-3 

Specifications: Physical Characteristics 3-4 

Option Port Wiring Configuration 5-12 

Row Driver Latch Bits 5-33 

Column Driver Latch Bits 5-36 

Controller Periods 5-37 

Calibration Performance Check - Equipment Required 6-1 

Adjustment Procedures - Equipment Required 6-24 

Main Board Voltages, Tolerances, Test Point Locations 6-27 

Maintenance - Equipment Required 7-1 

Power Cord Conductor Color Code 7-7 

Sealing Materials 7-20 



viii 



1502B MTDR Service Manual 



General Safety Summary 



The safety information in this summary is for operating personnel. Specific 
warnings and cautions will be found throughout the manual where they apply, but 
might not appear in this summary. For specific service safety information, see page 
xiii. 



Safety Terms and Symbols Terms in this manual: 



WARNING . Warning statements identify conditions or practices that could result in 
injury or loss of life. 



CAUTION. Caution statements identify conditions or practices that could result in 
damage to this product or other property. 





Terms on the Product: 

DANGER indicates an injury hazard immediately accessible as you read the 
marking. 

WARNING indicates an injury hazard not immediately accessible as you read the 
marking. 

CAUTION indicates a hazard to property including the product. 

Symbols in the Manual: 

A 

WARNING or CAUTION 
Information 

Symbols on the Product: 





© 


A 




□ 




DANGER 
High Voltage 


Protective Ground 
(Earth) Terminal 


ATTENTION 
Refer to 
Manual 


Double 

Insulated 



Power Source This product is intended to operate from a power source that will not apply more than 

250 volts RMS between the supply conductors or between the supply conductor and 



1502B MTDR Service Manual 



ix 




General Safety Summary 





ground. A protective ground connection, by way of the grounding conductor in the 
power cord, is essential for safe operation. 


Grounding the Product 


This product is grounded through the grounding conductor of the power cord. To 
avoid electrical shock, plug the power cord into a properly wired receptacle before 
connecting to the product input or output terminals. A protective ground connection 
by way of the grounding conductor in the power cord is essential for safe operation. 


Danger Arising from Loss 
of Ground 


Upon loss of the protective-ground connection, all accessible conductive parts 
(including knobs and controls that appear to be insulating) can render an electric 
shock. 


Use the Proper Power 
Cord 


Use only the power cord and connector specified for this product. Do not use this 
instrument without a rated AC line cord. 

The standard power cord ( 1 61-0288-00) is rated for outdoor use. All other optional 
power cords are rated for indoor use only. 

Use only a power cord that is in good condition. 

Refer cord and connector changes to qualified service personnel. 


Use the Proper Fuse 


To avoid fire hazard, use only a fuse of the correct type. 
Refer fuse replacement to qualified service personnel. 


Do Not Operate in 
Explosive Atmosphere 


To avoid explosion, do not operate this product in an explosive atmosphere unless 
it has been specifically certified for such operation. 


Do Not Remove Covers or 
Panels 


To avoid personal injury, do not remove the product covers or panels. Do not operate 
the product without the covers and panels properly installed. 



x 



1502B MTDR Service Manual 



Service Safety Summary 





Only qualified personnel should perform service procedures. Read this Service 
Safety Summary and the General Safety Summary before performing any service 
procedures. 


Do Not Service Alone 


Do not perform internal service or adjustments of this product unless another person 
capable of rendering first aid and resuscitation is present. 


Disconnect Power 


To avoid electric shock, disconnect the main power by means of the power cord or 
the power switch. 


Use Care When Servicing 
With Power On 


Dangerous voltages or currents may exist in this product. Disconnect power, remove 
battery, and disconnect test leads before removing protective panels, soldering, or 
replacing components. 

To avoid electric shock, do not touch exposed connections. 


Disposal of Batteries 


This instrument contains a NiCad battery pack. Some states and/or local 
jurisdictions might require special disposition/recycling of this type of material in 
accordance with Hazardous Waste guidelines. Check your local and state 
regulations prior to disposing of an old battery pack. 

Tektronix Factory Service will accept 1502B batteries for recycling. If you choose 
to return the battery to us for recycling, the battery cases must be intact, the battery 
should be packed with the battery terminals insulated against possible short-circuits, 
and should be packed in shock-absorbant material. 

Send batteries, post-paid, to: 

Tektronix, Inc. 

Attn: Bend Service 
100 S.E. Wilson Ave. 

Bend, OR 97702 

For additional information, phone: 1-800-835-9433. 



1502B MTDR Service Manual xi 




Service Safety Summary 



xii 



1502B MTDR Service Manual 



General Information 



Product Description 


The Tektronix 1502B Metallic-cable Time-Domain Reflectometer (MTDR) is a 
cable test instrument that uses radar principles to determine the electrical 
characteristics of metallic cables. 

The 1502B generates a half-sine wave signal, applies it to the cable under test, and 
detects and processes the reflected voltage waveform. These reflections are 
displayed in the 1502B liquid crystal display (LCD), where distance measurements 
may be made using a cursor technique. Impedance information may be obtained 
through interpreting waveform amplitude. 

The waveform may be temporarily stored within the 1502B and recalled or may be 
printed using the optional dot matrix strip chart recorder, which installs into the 
front-panel Option Port. 


Battery Pack 


The 1502B may be operated from an AC power source or a battery pack consisting 
of nine NiCad C-cells, which supply a minimum of five hours operating time (see 
the Specifications chapter for specifics). 


Options 


Options available for the 1502B are explained in the Options and Accessories 
chapter of this manual. 


Standards, Documents, 
and References Used 


Terminology used in this manual is in accordance with industry practice. 
Abbreviations are in accordance with ANSI Yl. 1-19722, with exceptions and 
additions explained in parentheses in the text. Graphic symbology is based on ANSI 
Y32. 2-1975. Logic symbology is based on ANSI Y32. 14-1973 and manufacturer’s 
data books or sheets. A copy of ANSI standards may be obtained from the Institute 
of Electrical and Electronic Engineers, 345 47th Street, New York, NY 10017. 


Changes and History 
Information 


Changes that involve manual corrections and/or additional data will be incorporated 
into the text and that page will show a revision date on the inside bottom edge. 
History information is included in any diagrams in gray. 



1502B MTDR Service Manual xiii 




General Information 



Installation and Repacking 



Unpacking and Initial 
Inspection 


Before unpacking the 1502B from its shipping container or carton, inspect for signs 
of external damage. If the carton is damaged, notify the carrier. The shipping carton 
contains the basic instrument and its standard accessories. Refer to the replaceable 
parts list in the Service Manual for a complete listing. 

If the contents of the shipping container are incomplete, if there is mechanical 
damage or defect, or if the instrument does not meet operational check requirements, 
contact your local Tektronix Field Office or representative. If the shipping container 
is damaged, notify the carrier as well as Tektronix. 

The instrument was inspected both mechanically and electrically before shipment. 
It should be free if mechanical damage and meet or exceed all electrical 
specifications. Procedures to check operational performance are in the Performance 
Checks appendix. These checks should satisfy the requirements for most receiving 
or incoming inspections. 


Power Source and Power 
Requirements 


The 1502B is intended to be operated from a power source that will not apply more 
than 250 volts RMS between the supply conductors or between either supply 
conductor and ground. A protective ground connection, by way of the grounding 
conductor in the power cord, is essential for safe operation. 

The AC power connector is a three-way polarized plug with the ground (earth) lead 
connected directly to the instrument frame to provide electrical shock protection. If 
the unit is connected to any other power source, the unit frame must be connected 
to earth ground. 

Power and voltage requirements are printed on the back panel. The 1502B can be 
operated from either 115 VAC or 230 VAC nominal line voltage at 45 Hz to 440 Hz, 
or a 12 VDC supply, or a battery pack. 

Further information on the 1502B power requirements can be found in the Safety 
Summary in this section and in the Operating Instructions chapter. 


Repacking for Shipment 


When the 1502B is to be shipped to a Tektronix Service Center for service or repair, 
attach a tag showing the name and address of the owner, name of the individual at 
your firm who may be contacted, the complete serial number of the instrument, and 
a description of the service required. If the original packaging is unfit for use or is 
not available, repackage the instrument as follows: 

1. Obtain a carton of corrugated cardboard having inside dimensions that are at 
least six inches greater than the equipment dimensions to allow for cushioning. 
The test strength of the shipping carton should be 275 pounds (102.5 kg). Refer 
to the following table for test strength requirements: 



xiv 



1502B MTDR Service Manual 



General Information 



SHIPPING CARTON TEST STRENGTH 



Gross Weight (lb) 


Carton Test Strength (lb) 


0-10 


200 


11-30 


275 


31 - 120 


375 


121 - 140 


500 


141 - 160 


600 




CAUTION. The Option 03 battery pack should be removed from the instrument before 
shipping. If it is necessary to ship the battery, it should be wrapped and secured 
separately before being packed with the instrument. 



2 . Install the front cover on the 1502B and surround the instrument with 
polyethylene sheeting to protect the finish. 

3. Cushion the instrument on all sides with packing material or urethane foam 
between the carton and the sides of the instrument. 

4 . Seal with shipping tape or an industrial stapler. 

If you have any questions, contact your local Tektronix Field Office or 
representative. 



1502B MTDR Service Manual 



xv 



General Information 



xvi 



1502B MTDR Service Manual 



Operating Instructions 



Overview 



Handling The 1502B front panel is protected by a watertight cover, in which the standard 
accessories are stored. Secure the front cover by snapping the side latches outward. 
If the instrument is inadvertently left on, installing the front cover will turn off the 
POWER switch automatically. 

The carrying handle rotates 325° and serves as a stand when positioned beneath the 
instrument. 

Inside the case, at the back of the instrument, is a moisture-absorbing canister 
containing silica gel. In extremely wet environments, it might be be necessary to 
periodically remove and dry the canister. This procedure is explained in the 1502B 
Service Manual. 

The 1502B can be stored in temperatures ranging from -62° C to +85° C. However, 
if the temperature is below -40° C or above +55° C, the battery pack should be 
removed and stored separately. Battery storage temperature should be -40° C to 
+55° C. 

Powering the 1502B In the field, the 1502B can be powered using the optional internal battery. For AC 

operation, check the rear panel for proper voltage setting. The voltage selector can 
be seen through the window of the protective cap. If the setting differs from the 
voltage available, it can be easily changed. Simply remove the protective cap and 
select the proper voltage using a screwdriver. 




Figure 1-1 : Rear Panel Voltage Selector, Fuse, AC Receptacle 



1502B MTDR Service Manual 



1-1 




Operating Instructions 




Care of the Optional 
Battery Pack 




Battery Charging 



The 1502B is intended to be operated from a power source that will not apply more 
than 250 V RMS between the supply conductors or between either supply conductor 
and ground. A protective ground connection by way of the grounding conductor in 
the power cord is essential for safe operation. 

The AC power connector is a three-way polarized plug with the ground (earth) lead 
connected to the instrument frame to provide electrical shock protection. If the unit 
is connected to any other power source, the unit frame must be connected to an earth 
ground. See Safety and Installation section. 



CAUTION. If you change the voltage selector, you must change the line fuse to the 



appropriate value as listed near the fuse holder and in the table below. 


FUSE RATING 


VOLTAGE RATING 


250 V 


NOMINAL RANGE 


0.3 AT 


115 VAC (90 - 132 VAC) 


0.15 AT 


230 VAC (180 -250 VAC) 



CAUTION. Read these instructions concerning the care of the optional battery pack. 
They contain instructions that reflect on your safety and the performance of the 
instrument. 



The 1502B can be powered by an optional rechargeable Nickel-cadmium battery 
pack that is accessible from the back of the instrument without removing the case. 
When AC power is applied, the battery pack is charged at a continuous rate of 
approximately 150 mA. 

The battery pack will operate the 1502B for a minimum of five continuous hours 
(including making 20 chart recordings) if the LCD backlight is turned off. 



The battery pack will charge fully in 16 hours when the instrument is connected, via 
the power cord, to an AC power source with the instrument turned off. The 
instrument may be turned on and operated while the batteries are charging, but this 
will increase the charging time. For longest battery life, a full charge is preferred 
over a partial charge. 

For maximum capacity, the batteries should be charged within a temperature range 
of +20° C to +25° C. However, the batteries can be charged within a temperature 
range of 0° C to +40° C and operated in temperatures ranging from -15° C to +55° C. 



1-2 



1502B MTDR Service Manual 



Operating Instructions 




CAUTION. Do not charge battery pack below 0° C or above +45° C. Do not 
discharge battery pack below -20° C or above + 65 ° C. If removing the battery pack 
during or after exposure to these extreme conditions , turn the instrument off and 
remove the AC power cord. Move the instrument to an ignition-free area before 
removing the battery pack. 



If the instrument is operated beyond the previously stated limits, turn off the 
instrument and either disconnect the AC power or remove the battery pack. 

If the instrument is shipped, the battery pack should be removed. If the instrument 
is stored with the battery pack installed, the battery pack should be charged every 
30 days. A fully charged battery pack will lose about 50% of its capacity in three 
to four months if stored between +20° C and +25° C. 

The batteries can be damaged by reverse charging. This can occur when an 
individual cell becomes discharged before the others and current from the other cells 
flows in a reverse direction through the discharged cell. Reverse charging might 
develop because of individual cell aging, partial charging of the battery pack, or if 
a single cell has been replaced rather than the entire pack. 



LOW Battery If the battery is low, it will be indicated on the LCD (bat/low). If this is the case, 
protective circuitry will shut down the 1502B within minutes. Switch to AC power, 
change the battery, or work very fast. If the instrument is equipped with a chart 
recorder, using the recorder will further reduce the battery level, or the added load 
might shut down the instrument. 




Low Battery 
Indicator 



Protection circuits in the charger prevent deep discharge of the batteries during 
instrument operation. The circuits automatically shut down the instrument 
whenever battery voltage falls below approximately 10 V. If shutdown occurs, the 
batteries should be fully recharged before further use. 



1502B MTDR Service Manual 



1-3 



Operating Instructions 



NOTE. Turn the POWER switch off after instrument shutdown to prevent continued 
discharge of the batteries. 

Under low AC line voltage conditions, the AC fuse ratings might be exceeded if the 
battery if fully discharged and a chart recording is being made. Allow the battery 
to charge for about one hour before attempting to make a chart recording, or use 
AC only. 



LOW Temperature When operating the 1502B in an environment below +10° C, a heater will activate. 

0 peration The element is built into the LCD module and will heat the display to permit normal 

operation. Depending on the surrounding temperature, it might take up to 15 
minutes to completely warm the crystals in the LCD. Once warmed, the display will 
operate normally. 



Preparing to Use the 1502B 

Check the power requirements, remove the front cover, and you are ready to test 
cables. The following pages explain the front-panel controls. 




Figure 1-3: 1502B Front-Panel Controls 



1-4 



1502B MTDR Service Manual 



Operating Instructions 




CAUTION. Do not connect live circuits to the CABLE connector. Voltages exceeding 
5 volts can damage the driver or sampler circuits. 

Bleed the test cable of any residual static charge before attaching it to the 
instrument. To bleed the cable, connect the standard 50Q terminator and standard 
female-to-female BNC connector together, then temporarily attach both to the 
cable. Remove the connectors before attaching the cable to the instrument. 



When testing receiving antenna cables, avoid close proximity to transmitters. 
Voltages may appear on the cable if a nearby transmitter is in use, resulting in 
damage to the instrument. Before testing, be sure that there are no RF voltages 
present, or disconnect the cable at both ends. 



Display 



Power Front-Panel to Cursor 

Type Waveform Cursor Distance Window 









L_I_ 


View Input 

Indicator 

View Store 


i 

? 

e 


ac 












0.000 ft 






































r. 






















1 








Indicator 
View Difference 

1 nHir'dtnr 








r~. 


A_/ — ^ 
































If lUlUcUUf 

Store yj 
Indicator 


























1 avq 




500 


mo 


0.; 


2 ft 







Selected Selected Selected 
Noise Filter Vertical Scale Distance per 



Grid 



Division 



Figure 1-4: Display and Indicators 



Front-Panel Controls 



NOISE FILTER 




HORZ 

vert — ^ SET REF 



1. CABLE: A female BNC connector for attaching a cable to the 1502B for 
testing. 

2. NOISE FILTER: If the displayed waveform is noisy, the apparent noise can 
be reduced by using noise averaging. Averaging settings are between 1 and 128. 
The time for averaging is directly proportional to the averaging setting chosen. 
A setting of 128 might take the instrument up to 35 seconds to acquire and 
display a waveform. The first two positions on the NOISE FILTER control are 
used for setting the vertical and horizontal reference points. The selected value 
or function is displayed above the control on the LCD. 



1502B MTDR Service Manual 



1-5 



Operating Instructions 



VERT SCALE 




DIST/DIV 





POWER AA 

(PULL ON) V_y 



A 

V 



POSITION 




<> POSITION 




MENU 



VIEW 

INPUT 



VIEW 

STORE 



VIEW 

DIFF 



3. VERT SCALE: This control sets the vertical sensitivity, displayed in mp per 
division, or the vertical gain, displayed in dB. Although the instrument defaults 
to millirho, you may choose the preferred mode from the Setup Menu. The 
selected value is displayed above the control on the LCD. 

4. DIST/DIV: Determines the number of feet (or meters) per division across the 
display. The minimum setting is 0.1 ft/div (0.025 meters) and the maximum 
setting is 200 ft/div (50 meters). The selected value is displayed above the 
control on the LCD. 

A standard instrument defaults to ft/div. A metric instrument (Option 05) 
defaults to m/div, but either may be changed temporarily from the menu. The 
default can be changed by changing an internal jumper (see 1502B Service 
Manual and always refer such changes to qualified service personnel). 

5. Vp: The two Velocity of Propagation controls are set according to the 
propagation velocity factor of the cable being tested. For example, solid 
polyethylene commonly has a Vp of 0.66. Solid poly tetrafloure thy lene (Teflon 
®) is approximately 0.70. Air is 0.99. The controls are decaded: the left control 
is the first digit and the right control is the second digit. For example, with a Vp 
of 0.30, the first knob would be set to .3 and the second knob to .00. 

6. POWER: Pull for power ON and push in for power OFF. When the front cover 
is installed, this switch is automatically pushed OFF. 

7. 0 POSITION: This is a continuously rotating control that positions the 
displayed waveform vertically, up or down the LCD. 

8. <]> POSITION: This is a continuously rotating control that moves a vertical 
cursor completely across the LCD graticule. In addition, the waveform is also 
moved when the cursor reaches the extreme right or left side of the display. A 
readout (seven digits maximum) is displayed in the upper right corner of the 
LCD, showing the distance from the front panel BNC to the current cursor 
location. 

9. MENU : This pushbutton provides access to the menus and selects items chosen 
from the menus. 

10. VIEW INPUT: When pushed momentarily, this button toggles the display of 
the waveform acquired at the CABLE connector. This function is useful to stop 
displaying a current waveform to avoid confusion when looking at a stored 
waveform. This function defaults to ON when the instrument is powered up. 

11. VIEW STORE: When pushed momentarily, this button toggles the display of 
the stored waveform. 

12. VIEW DIFF : When pushed momentarily, this button toggles the display of the 
current waveform minus the stored waveform and shows the difference between 
them. 



1-6 



1502B MTDR Service Manual 



Operating Instructions 



STORE — > 



Menu Selections 



Main Menu 



13. STORE: When pushed momentarily, the waveform currently displayed will be 
stored in the instrument memory. If a waveform is already stored, pushing this 
button will erase it. The settings of the stored waveform are available from the 
first level menu under View Stored Waveform Settings. 



There are several layers of menu, as explained below. 

The Main Menu is entered by pushing the MENU button on the front panel. 

1. Return to Normal Operations puts the instrument into normal operation 
mode. 

2. Help with Instrument Controls explains the operation of each control. When 
a control or switch is adjusted or pushed, a brief explanation appears on the 
LCD. 

3. Cable Information has these choices: 

a. Help with Cables gives a brief explanation of cable parameters. 

b. Velocity of Propagation Values displays a table of common dielectrics and 
their Vp values. These are nominal values. The manufacturer’s listed 
specifications should be used whenever possible. 

c. Impedance Values displays impedances of common cables. In some cases, 
these values have been rounded off. Manufacturer’s specifications should 
be checked for precise values. 

d. Finding Unknown Vp Values describes a procedure for finding an 
unknown Vp. 

4. Setup Menu controls the manner in which the instrument obtains and displays 
its test results. 

a. Acquisition Control Menu has these choices: 

i. Max Hold Is: On/Off. Turn Max Hold on by pushing MENU then 
STORE. In this mode, waveforms are accumulated on the display. Max 
Hold can be deactivated by pushing STORE or the mode exited by 
using the Setup Menu. 

ii. Pulse Is: On/Off. Turns the pulse generator off so the 1502B does not 
send out pulses. 

iii. Single Sweep Is: On/Off. This function is much like a still camera; it 
will acquire one waveform and hold it. 



1502B MTDR Service Manual 



1-7 



Operating Instructions 



b. Ohms-at-Cursor is: On/Off. When activated, the impedance at thee point 
of the cursor is displayed beneath the distance window on the display. 

c. Vertical Scale Is: dB/mp. This offers you a choice as to how the vertical 
gain of the instrument is displayed. You may choose decibels or millirho. 
When powered down, the instrument will default to millirho when powered 
back up. 

d. Distance/Div Is: ft/m. Offers you a choice of how the horizontal scale is 
displayed. You may choose from feet per division or meters per division. 
When powered up, the instrument will default to feet unless the internal 
jumper has been moved to the meters position. Instructions on changing this 
default are contained in the 1502B Service Manual. 

e. Light Is: On/Off. This control turns the electroluminescent backlight 
behind the LCD on or off. 

5. Diagnostics Menu lists an extensive selection of diagnostics to test the 
operation of the instrument. 



NOTE. The Diagnostics Menu is intended for instrument repair and calibration. 
Proper instrument setup is important for correct diagnostics results. Refer to the 
1502B Service Manual for more information on diagnostics. 



a. Service Diagnostics Menu has these choices: 

i. Sampling Efficiency Diagnostic displays a continuous efficiency 
diagnostic of the sampling circuits. 

ii. Noise Diagnostic measures the internal RMS noise levels of the 
instrument. 

iii. Offset/Gain Diagnostic reports out-of-tolerance steps in the program- 
mable gain stage. This can help a service technician to quickly isolate 
the cause of waveform distortion problems. 

iv. RAM/ROM Diagnostics Menu performs tests on the RAM (Random 
Access Memory) and the ROM (Read Only Memory). 

v. Timebase Is: Normal - Auto Correction / Diagnostic - No 
Correction. When in Normal - Auto Correction , the instrument 
compensates for variations in temperature and voltage. This condition 
might not be desirable while calibrating the instrument. While in 
Diagnostic - No Correction , the circuits will not correct for these 
variations. 

b. Front Panel Diagnostics aids in testing the front panel. 



1-8 



1502B MTDR Service Manual 



Operating Instructions 



c. LCD Diagnostics Menu has these choices: 

i. LCD Alignment Diagnostic generates a dot pattern of every other 
pixel on the LCD. These pixels can be alternated to test the LCD. 

ii. Response Time Diagnostic generates alternate squares of dark and 
light, reversing their order. This tests the response time of the LCD and 
can give an indication of the effectiveness of the LCD heater in a cold 
environment. 

iii. LCD Drive Test Diagnostic generates a moving vertical bar pattern 
across the LCD. 

iv. Contrast Adjust allows you to adjust the contrast of the LCD. It 
generates an alternating four-pixel pattern. The nominal contrast is set 
internally. When in Contrast Adjust mode, VERT SCALE is used as the 
contrast adjustment control. This value ranges from 0 to 255 units and 
is used by the processor to evaluate and correct circuit variations caused 
by temperature changes in the environment. When the diagnostic menu 
is exited, the LCD contrast returns to that set by internal adjust. 

d. Chart Diagnostics Menu offers various tests for the optional chart 
recorder. 

i. LCD Chart allows adjusting the number of dots per segment and the 
number of prints (strikes) per segment. 

ii. Head Alignment Chart generates a pattern to allow mechanical 
alignment of the optional chart recorder. 

6. View Stored Waveform Settings displays the instrument settings for the stored 
waveform. 

7. Option Port Menu contains three items. Two items allow configuration of the 
option port for communicating with devices other than the optional chart 
recorder and one item test the option port. 

a. Option Port Diagnostic creates a repeating pattern of signals at the option 
port to allow service technicians to verify that all signals are present and 
working correctly. 

b. Set Option Port Timing allows adjustment of the data rate used to 
communicate with external devices. The timing rate between bytes can be 
set from about 0.05 to 12.8 milliseconds. 

c. Option Port Debugging Is Off/On. Off is quiet, On is verbose. This 
chooses how detailed the error message reporting will be when communi- 
cating with an external device. 

It is possible to connect the instrument to a computer through a parallel interface 
with a unique software driver. Because different computers vary widely in 



1502B MTDR Service Manual 



1-9 



Operating Instructions 



Test Preparations 

The Importance of Vp 
(Velocity of Propagation) 



Vp of Various Dielectric 
Types 



processing speed, the instrument must be able to adapt to differing data rates 
while communicating with those computers. With user-developed software 
drivers, the ability to obtain detailed error messages during the development can 
be very useful. For more information, contact your Tektronix Customer Service 
representatives. They have information describing the option port hardware and 
software protocol and custom development methods available. 

8. Display Contrast (Software Version 5.02 and above) 

a. Press the MENU button firmly once. If the display is very light or very dark, 
you might not be able to see a change in the contrast. 

b. Turn the VERTICAL SCALE knob slowly clockwise to darken the display 
or counterclockwise to lighten the display. If you turn the knob far enough, 
the contrast will wrap from the darkest to lightest value. 

c. When the screen is clearly readable, press the MENU button again to return 
to normal measurement operation. The new contrast value will remain in 
effect until the instrument is turned off. 



Vp is the speed of a signal down the cable given as a percentage of the speed of light 
in free space. It is sometimes expressed as a whole number (e.g., 66) or a percentage 
(e.g., 66%). On the 1502B, it is the percentage expressed as a decimal number (e.g., 
66% = .66). If you do not know the velocity of propagation, you can get a general 
idea from the following table, or use the Help with Cables section of the Cable 
Information menu. You can also find the Vp with the procedure that follows using 
a cable sample. 



NOTE. If you do not know the Vp of your cable, it will not prevent you from finding 
a fault in your cable. However, if the Vp is set wrong, the distance readings will be 
affected. 

All Vp settings should be set for the cable under test, not the supplied jumper cable. 



Dielectric 


Probable Vp 


Jelly Filled 


.64 


Polyethylene (PIC, PE, or SPE) 


.66 


PTFE (Teflon ®) or TFE 


.70 


Pulp Insulation 


.72 


Foam or Cellular PE (FPE) 


.78 


Semi-solid PE (SSPE) 


.84 


Air (helical spacers) 


.98 



1-10 



1502B MTDR Service Manual 



Operating Instructions 



Finding an Unknown Vp 



1. Obtain a known length of cable of the exact type you wish to test. Attach the 
cable to the CABLE connector on the front panel. 

2. Pull POWER on. 

3. Turn the DIST/DIV to an appropriate setting (e.g., if trying to find the Vp of a 
three-foot cable, turn the DIST/DIV to 1 ft/di v). 

4. Turn the POSITION control until the distance reading is the same as the 
known length of this cable. 

5. Turn the Vp controls until the cursor is resting on the rising portion of the 
reflected pulse. The Vp controls of the instrument are now set to the Vp of the 
cable. 

The following three illustrations show settings too low, too high, and correct for a 

sample three-foot cable. 




Figure 1-5: Vp Set at .30, Cursor Beyond Reflected Pulse (Set Too Low) 




Figure 1-6: Vp Set at .99, Cursor Less Than Reflected Pulse (Set Too High) 



1502B MTDR Service Manual 



1-11 



Operating Instructions 



Cable Test Procedure 

Distance to the Fault 




Be sure to read the previous paragraphs on Vp. 
1. Set the 1502B controls: 



POWER 
CABLE 
NOISE FILTER 
VERT SCALE 
DIST/DIV 
Vp 



On 

Cable to BNC 
1 avg 
500 mp 
(see below) 
(per cable) 



2. If you know approximately how long the cable is, set the DIST/DIV 
appropriately (e.g., 20-ft cable would occupy four divisions on the LCD if 5 
ft/div was used). The entire cable should be displayed. 




If the cable length is unknown, set DIST/DIV to 200 ft/div and continue to decrease 
the setting until the reflected pulse is visible. Depending on the cable length and the 
amount of pulse energy absorbed by the cable, it might be necessary to increase the 
VERT SCALE to provide more gain to see the reflected pulse. 



1-12 



1502B MTDR Service Manual 



Operating Instructions 




Short 



When the entire cable is displayed, you can tell if there is an open or a short. 
Essentially, a large downward pulse indicates a short (see Figure 1-9), while a large 
upward pulse indicates an open (see Figure 1-10). Less catastrophic faults can bee 
seen as smaller reflections. Bends and kinks, frays, water, and interweaving all have 
distinctive signatures. 




Open 



3. To find the distance to the fault or end of the cable, turn the <]> POSITION 
control until the cursor rests on the leading edge of the rising or falling reflected 
pulse (see Figure 1-10). Read the distance in the distance window in the upper 
right corner of the display. 

A more thorough inspection might be required. This example uses a longer cable: 

4 . When inspecting a 452-foot cable, a setting of 50 ft/div allows a relatively fast 
inspection. If needed, turn VERT SCALE to increase the gain. The higher the 
gain, the smaller the faults that can be detected. If noise increases, increase the 
NOISE FILTER setting. 



1502B MTDR Service Manual 



1-13 



Operating Instructions 



Reflection Coefficient 
Measurements 




Open 



Figure 1-11 : 455-ft Cable 

5. Change DIST/DIV to 20 ft/div. The entire cable can now be inspected in detail 
on the LCD. Turn the <> POSITION control so the cursor travels to the far right 
side of the LCD. Keep turning and the cable will be “dragged” across the 
display. 




Figure 1-12: 455-ft Cable 

A “rise” or “fall” is a signature of an impedance mismatch (fault). A dramatic rise 
in the pulse indicates and open. A dramatic lowering of the pulse indicates a short. 
Variations, such as inductive and capacitive effects on the cable, will appears as 
bumps and dips in the waveform. Capacitive faults appear as a lowering of the pulse 
(e.g., water in the cable). Inductive faults appear as a rising of the pulse (e.g., fray). 
Whenever an abnormality is found, set the cursor at the beginning of the fault and 
read the distance to the fault on the distance window of the LCD. 



The reflection coefficient is a measure of the impedance change at a point in the 
cable. It is the ratio of the signal reflected back from a point, divided by the signal 
going into that point. It is designated by the Greek letter p and is written in this 
manual as rho. The 1502B measures the reflection coefficient in millirho 
(thousandths of a rho). 

To measure a reflection, adjust VERT SCALE to make the reflection one division 
high. Read the reflection coefficient directly off the display above the VERT 



1-14 



1502B MTDR Service Manual 



Operating Instructions 



Return Loss 
Measurements 



SCALE control. For reflections that are greater than 500 mp/div, adjust VERT 
SCALE for a reflection that is two divisions high and multiply the VERT SCALE 
reading by two. 




Figure 1-13: Reflection Adjusted to One Division in Height 

In an ideal transmission system with no changes in impedance, there will be no 
reflections, so rho is equal to zero. A good cable that is terminated in its 
characteristic impedance is close to ideal and will appear as a flat line on the 1502B 
display. 

Small impedance changes, like those from a connector, might have reflections from 
10 to 100 mp. If rho is positive, it indicates an impedance higher than that of the 
cable before the reflection. It will show as an upward shift or bump on the waveform. 
If rho is negative, it indicates an impedance lower than that of the cable prior to the 
reflection. It will show as a downward shift or dip on the waveform. 

If the cable has an open or short, all the energy sent out by the 1502B will be 
reflected. This is a reflection coefficient of rho = 1, or +1000 mp for the open and 
-1000 mp for the short. 

Long cables have enough loss to affect the size of reflections. In the 1502B, this loss 
will usually be apparent as an upward ramping of the waveform along the length of 
the cable. In some cases, the reflection coefficient measurement can be corrected for 
this loss. This correction can be made using a procedure very similar to the Vertical 
Compensation for Higher Impedance Cable procedure (see the VERT SET REF 
section). 



Return loss is another was of measuring impedance changes in a cable. 
Mathematically, return loss is related to rho by the formula: 

Return Loss (in dB) = -20 * log (base ten) of Absolute Value of Rho (Vref/Vinc) 

The 1502B can be made to display in dB instead of mp/div through the menu: 

1. Press MENU. 



1502B MTDR Service Manual 



1-15 



Operating Instructions 



Ohms-at-Cursor 



2. Select Setup Menu. 

3. Press MENU again. 

4. Select Vertical Scale is: Millirho. 

5. Press MENU again. This should change is to Vertical Scale is: Decibels. 

6. Press MENU twice to return to normal operation. 

To measure return loss with the 1502B, adjust the height of the reflected pulse to 
be two divisions high and read the dB return loss directly off the LCD. The incident 
pulse is set to be two divisions high at zero dB automatically when the instrument 
is turned on. 




Figure 1-14: Return Loss 

A large return loss means that most of the pulse energy was lost instead of being 
returned as a reflection. The lost energy might have been sent down the cable or 
absorbed by a terminator or load on the cable. A terminator matched to the cable 
would absorb most of the pulse, so its return loss would be large. An open or short 
would reflect all the energy, so its return loss would be zero. 



The 1502B can compute and display what impedance mismatch would cause a 
reflection as high (or low) as the point at the cursor. This measurement is useful for 
evaluating the first impedance mismatch (first reflection) or small impedance 
changes along the cable (e.g., connectors, splices). 



This function can be selected in the Setup Menu. Once it is enabled, the impedance 
value will be displayed under the distance in the distance window. 



1-16 



1502B MTDR Service Manual 



Operating Instructions 



Using VIEW INPUT 




Ohms-at-Cursor 

Readout 



Figure 1-15: Ohms-at-Cursor 

The accuracy of the difference measurement in impedance between two points near 
each other is much better than the absolute accuracy of any single point 
measurement. For example, a cable might vary from 51.3Q to 58.4Q across a 
connector - the 7.1Q difference is accurate to about 2%. The 51.3Q measurement 
by itself is only specified to be accurate to 10%. 



The series resistance of the cable to the point at the cursor affects the accuracy of 
the impedance measurement directly. In a cable with no large impedance changes, 
the series resistance is added to the reading. For example, the near end of a long 50Q 
coaxial cable might read 51.5Q, but increase to 57. 5Q several hundred feet along 
the cable. The 6Q difference is due to the series resistance of the cable, not to a 
change in the actual impedance of the cable. 



Another limitation to the ohms-at-cursor function is that energy is lost going both 
directions through a fault. This will cause readings of points farther down the cable 
to be less accurate than points nearer to the instrument. 



In general, it is not wise to try to make absolute measurements past faults because 
the larger the fault, the less accurate those measurements will be. Although they do 
not appear as faults, resistive pads (often used to match cable impedances) also 
affect measurements this way. 



When pushed, the VIEW INPUT button displays the input at the front panel CABLE 
connector. When VIEW INPUT is turned off and no other buttons are pushed, the 
display will not have a waveform on it (see Figure 1-16, next page). The default 
condition when the instrument is powered up is to have VIEW INPUT on. 



1502B MTDR Service Manual 



1-17 



Operating Instructions 



How to Store the 
Waveform 



Using VIEW STORE 




Figure 1-16: Display with VIEW INPUT Turned Off 

When pushed, the STORE button puts the current waveform being displayed into 
memory. If already stored, pushing STORE again will erase the stored waveform. 

The front panel control settings and the menu-accessed settings are also stored. They 
are accessed under View Stored Waveform Settings in the first level of the menu. 




The VIEW STORE button, when pushed on, displays the waveform stored in the 
memory as a dotted line. If there is no waveform in memory, a message appears on 
the LCD informing you of this. 



ac 










3.000 ft ! 
































<r — ' 


















l 












in 


r 

. . 1 . . 





















1 


















F 




















1 





















Figure 1-18: Display of a Stored Waveform 



1-18 



1502B MTDR Service Manual 



Operating Instructions 



Using VIEW DIFF When pushed on, the VIEW DIFF button displays the difference between the current 

waveform and the stored waveform as a dotted line. If no waveform has been stored, 
a message will appear. The difference waveform is made by subtracting each point 
in the stored waveform from each point in the current waveform. 



NOTE. If the two waveforms are identical ( e.g., if STORE is pushed and VIEW DIFF 
is immediately pushed ) the difference would be zero. Therefore you would see the 
difference waveform as a straight line. 



The VIEW DIFF waveform will move up and down with the current input as you 
move the ^POSITION control. Any of the waveforms may be turned on or off 
independently. You might want to turn off some waveforms if the display becomes 
too busy or confusing. 



NOTE. Because the stored waveform is not affected by changes in the instrument 
controls, care should be taken with current waveform settings or the results could 
be misleading. 



One method to minimize the overlapping of the waveforms in VIEW DIFF is: 

1. Move the waveform to be stored into the top half of the display. 




2. Push STORE to capture the waveform. Remember, once it is stored, this 
waveform cannot be moved on the display. 

3. Move the current waveform (the one you want to compare against the stored 
waveform) to the center of the display. 

4 . Push VIEW STORE and the stored waveform will appear above the current 
waveform. 



1502B MTDR Service Manual 



1-19 



Operating Instructions 




Figure 1-20: Current Waveform Centered, Stored Waveform Above 

5. Push VIEW DIFF and the difference waveform will appear below the current 
waveform. 




Notice the VIEW INPUT waveform is solid, VIEW DIFF is dotted, and VIEW 
STORE is dot-dash. 

There are many situations where the VIEW DIFF function can be useful. One 
common situation is to store the waveform of a suspect cable, repair the cable, then 
compare the two waveforms after the repair. During repairs, the VIEW INPUT, 
VIEW DIFF, and VIEW STORE waveforms can be used to judge the effectiveness 
of the repairs. The optional chart recorder can be used to make a chart of the three 
waveforms to document the repair. 

Another valuable use for the VIEW DIFF function is for verifying cable integrity 
before and after servicing or periodic maintenance that requires moving or 
disconnecting the cable. 

The VIEW DIFF function is useful when you want to see any changes in the cable. 
In some systems, there might be several reflections coming back from each branch 
of the network. It might become necessary to disconnect branch lines from the cable 
under test to determine whether a waveform represents a physical fault or is simply 
an echo from one of the branches. The STORE and VIEW DIFF functions allow you 



1-20 



1502B MTDR Service Manual 



Operating Instructions 



Using Horizontal Set 
Reference 



to see and compare the network with and without branches. 



Two important things to be observed when using the VIEW DIFF function: 



■ If you change either the VERT SCALE or DIST/DIV, you will no longer be 
comparing features that are the same distance apart or of the same magnitude 
on the display. It is possible to save a feature (e.g., a connector or tap) at one 
distance down the cable and compare it to a similar feature at a different distance 
by moving the ^POSITION and 0 POSITION controls. 



■ When this is done, great care should be taken to make sure the vertical and 
horizontal scales are identical for the two waveforms being compared. If either 
the stored or current waveform is clipped at the top or bottom of the display, the 
difference waveform will be affected. 



HORZ SET REF (A mode) allows you to offset the distance reading. For example, 
a lead-in cable to a switching network is three feet long and you desire to start the 
measurement after the end of the lead-in cable. HORZ SET REF makes it simple. 




1. Turn the NOISE FILTER control to HORZ SET REF. The noise readout on the 
LCD will show: set A. 

2. Turn the ^POSITION control to set the cursor where you want to start the 
distance reading. This will be the new zero reference point. For a three-foot 
lead-in cable, the cursor should be set at 3.00 ft. 



1502B MTDR Service Manual 



1-21 



Operating Instructions 



ac 










3.000 ft 


1 . . . . 




















1 
























































r . 




























































• mo v 


e cur 


so r t 


o ref 

: i 


erenc 

i 


e and 


Pres: 


5 STOF 


jE • • • 



Figure 1-23: Cursor Moved to End of Three-Foot Lead-in Cable 

3. Push STORE. 

4. Turn the NOISE FILTER control to 1 avg. The instrument is now in HORZ SET 
REF, or delta mode. The distance window should now read 0.00 ft. As the cursor 
is scrolled down the cable, the distance reading will now be from the new zero 
reference point. 



ac 








0.000 ft A ! 


1 . . . . 
















1 


















. r . 








/" * * 
























... 

1 












































i 



Figure 1-24: Cursor Moved to End of Three-Foot Lead-in Cable 



NOTE. Vp changes will affect where the reference is set on the cable. Be sure to set 
the Vp first, then set the delta to the desired location. 



5. To exit HORZ SET REF, use the following procedure: 

a. Turn the NOISE FILTER control to HORZ SET REF. 

b. Turn DIST/DIV to .1 ft/div. If the distance reading is extremely high, you 
might want to use a higher setting initially, then turn to . 1 ft/div for the next 
adjustment. 

c. Turn the ^POSITION control until the distance window reads 0.00 ft. 



1-22 



1502B MTDR Service Manual 



Operating Instructions 



Using Vertical Set 
Reference 



ac 

1 . . . . 
















0.00( 


D ft ! 


1 








































/ 










. . f . 






























... 

1 
























' mo v 

_ _ . J 


e cur 

l _ _ _ 


so r t 


i ° 

1 ~3 

i n> 

— h 


erenc 


e and 


Press 


5 STOP 


If ’ •' 



Figure 1-25: Cursor Moved to 0.00 ft 

d. Push STORE. 

e. Turn NOISE FILTER to desired setting. 



VERT SET REF works similar to HORZ SET REF except that it sets a reference 
for gain (pulse height) instead of distance. This feature allows zeroing the dB scale 
at whatever pulse height is desired. 

1. Turn NOISE FILTER fully counterclockwise. “Set Ref’ will appear in the noise 
averaging area of the LCD. 

2. Adjust the incident pulse to the desired height (e.g., four divisions). It might be 
necessary to adjust y POSITION. 



ac 










0.000 ft 






















1 . . . . 


f. ■ • 










1 






































































































s e 1 

J 


t ve r 1 

[ : 


: i c a L 


scale 


i and 


press 


STOR 


E ' ' ' 





Figure 1-26: Incident Pulse at Three Divisions 

3. Push STORE. 

4. Return NOISE FILTER to the desired setting. Notice that the vertical scale now 
reads 500 mp/div. 



NOTE. The millirho vertical scale will not be in calibration after arbitrarily 
adjusting the pulse height. 



1502B MTDR Service Manual 



1-23 



Operating Instructions 



Vertical Compensation for 
Higher Impedance Cable 



The millirho scale is the reciprocal of the number of divisions high the pulse has 
been set. For example, 1 pulse divided by 4 divisions equals 0.25 or 250 mp/div. 



When testing cables other than 50Q, this procedure allows reflection measurements 
in millirho. 

1. Attach a short sample of the given cable (750 in this example)to the instrument. 




2. Adjust the ^POSITION control to position the reflected pulse at center screen. 

3. Turn NOISE FILTER to VERT SET REF. 

4. Adjust VERT SCALE so the reflected pulse (from open at far end of cable 
sample) is two divisions high. 



! ac 










19.200 ft 


1 . . . . 




















1 






























. . . > 












/ 


















L 




















i 




;e t ve 


; r t i ca 


i L sea 


L e an 


d pre 


ss ST 


ORE- • 





Figure 1-28: Waveform Centered and Adjusted Vertically 



5. Press STORE. 

6. Return NOISE FILTER to the desired setting. 

7. Adjust the ^POSITION control to the desired position on the waveform to 
measure loss. 



1-24 



1502B MTDR Service Manual 



Operating Instructions 




Figure 1-29: Cursor Moved to Desired Position 

The instrument is now set to measure reflections in millirho relative to the sample 
cable impedance. 

To measure reflections on a 50Q cable, the VERT SET REF must be reset. 

8. To exit VERT SET REF, use the following procedure: 



a. Turn NOISE FILTER to VERT SET REF. 

b. Adjust VERT SCALE to obtain an incident pulse height of two divisions. 

c. Push STORE. 

d. Turn NOISE FILTER to desire filter setting. 

The instrument can be turned off and back on to default to the two division pulse 
height. 



Additional Features (Menu Selected) 

Max Hold The 1502B will capture and store waveforms on an ongoing basis. This is useful 
when the cable or wire is subjected to intermittent or periodic conditions. The 1 502B 
will monitor the line and display any fluctuations on the LCD. 

1. Attach the cable to the 1502B front-panel CABLE connector. 

2. Push MENU to access the main menu. 

3. Scroll to Setup Menu and push MENU again. 

4. Scroll to Acquisition Control Menu and push MENU again. 

5. Scroll to Max Hold is: Off and push MENU again. This line will change to Max 
Hold is: On. The monitoring function is now ready to activate. 

6. Repeatedly push MENU until the instrument returns to normal operation. 



1502B MTDR Service Manual 



1-25 



Operating Instructions 



Pulse On/Off 




Figure 1-30: Waveform Viewed in Normal Operation 

7. When you are ready to monitor this cable for intermittent s, push STORE. The 
1502B will now capture any changes in the cable. 




Captured 

changes 



Figure 1-31 : Waveform Showing Intermittent Changes 



8. To exit monitor mode, push STORE again. 



9. To exit Max Hold, access the Acquisition Control Menu again, turn off Max 
Hold, and push MENU repeatedly until the instrument returns to normal 
operation. 



This feature puts the 1502B in a “listening mode” by turning off the pulse generator. 

1. Attach a cable to the 1502B front-panel CABLE connector. 

2. Push MENU to access the Main Menu. 

3. Scroll to Setup Menu and push MENU again. 

4. Scroll to Acquisition Control Menu and push MENU again. 

5. Scroll to Pulse is: On and push MENU again. This will change to Pulse is: Off. 



1-26 



1502B MTDR Service Manual 



Operating Instructions 




Figure 1-32: Waveform Display with No Outgoing Pulses 

6. Repeatedly press MENU until the instrument returns to normal operation. 




CAUTION. This function is used mostly for troubleshooting by qualified technicians. 
It is not recommended that you use the 1502B as a stand-alone monitoring device. 
The input circuitry is very sensitive and can be easily damaged by even moderate 
level signals. 



NOTE. In this mode, the 1502B is acting as a detector only. Any pulses detected will 
not originate from the instrument, so any distance readings will be invalid. If you 
are listening to a local area network, for example, it is possible to detect traffic, but 
not possible to measure the distance to its origin. 



Pulse is: Off cm be used in conjunction with Max Hold is: On. 

7. To exit Pulse is: Off, access the Acquisition Control Menu again, turn the pulse 
back on, then repeatedly push MENU until the instrument returns to normal 
operation. 



Single Sweep The single sweep function will acquire one waveform only and display it. 

1. Attach a cable to the 1502B front-panel CABLE connector. 

2. Push MENU to access the Main Menu. 

3. Scroll to Setup Menu and push MENU again. 

4. Scroll to Acquisition Control Menu and push MENU again. 

5. Scroll to Single Sweep is: Offmd push MENU again. This will change to Single 
Sweep is: On. 

6. Repeatedly press MENU until the instrument returns to normal operation. 



1502B MTDR Service Manual 



1-27 



Operating Instructions 



7. When you are ready to begin a sweep, push VIEW INPUT. A sweep will also 
be initiated when you change any of the front-panel controls. This allows you 
to observe front panel changes without exiting the Single Sweep mode. 

As in normal operation, averaged waveforms will take longer to acquire. 




Figure 1-33: A Captured Single Sweep 

8. To exit Single Sweep is: On , access the Acquisition Control Menu again, turn 
the Single Sweep back off, then repeatedly push MENU until the instrument 
returns to normal operation. 



1-28 



1502B MTDR Service Manual 



Operator Performance Checks 



Equipment Required 



Getting Ready 



Power On 



Metric Instruments 



This chapter contains performance checks for many of the functions of the 1502B. 
They are recommended for incoming inspections to verify that the instrument is 
functioning properly. Procedures to verify the actual performance requirements are 
provided in the 1502B Service Manual. 

Performing these checks will assure you that your instrument is in good working 
condition. These checks should be performed upon receipt of a new instrument or 
one that has been serviced or repaired. It does not test all portions of the instrument 
to Calibration specifications. 

The purpose of these checks is not to familiarize a new operator with the instrument. 
If you are not experienced with the instrument, you should read the Operating 
Instructions chapter of this manual before going on with these checks. 

If the instrument fails any of these checks, it should be serviced. Many failure modes 
affect only some of the instrument functions. 



Item 


Tektronix Part Number 


50Q precision terminator 


011-0123-00 


3-foot precision coaxial cable 


012-1350-00 



Disconnect any cables from the front-panel CABLE connector. Connect the 
instrument to a suitable power source (a fully charged optional battery pack or AC 
line source). If you are using AC power, make sure the fuse and power switch are 
correct for the voltage you are using (115 VAC requires a different fuse than 
230 VAC). 



Pull the POWER switch on the front panel. If a message does not appear on the 
display within a second or two, turn the instrument off. There are some failure modes 
that could permanently damage or ruin the LCD if the power is left on for more than 
a minute or so. 



Option 05 instruments default to metric; however, you can change the metric scale 
to ft/div in the Setup Menu or use the metric numbers provided. To change the 
readings, press the MENU button. Using the 0 POSITION control, scroll down to 
Setup Menu and press MENU again. Scroll down to Distance/Div is: m/div and press 
MENU again. This will change to ft/div. Press the MENU button repeatedly to 
return to normal operation mode. If the instrument power is turned off, these checks 
must be repeated again when the instrument is powered on again. 



1502B MTDR Service Manual 



2-1 




Operator Performance Checks 



Set Up 



1. Horizontal Scale 
(Timebase) Check 



Set the 1502B front-panel controls: 



NOISE FILTER 
VERT SCALE 
DIST/DIV 
Vp 



1 avg 

no adjustment 
1 ft/div (0.25 m) 
.66 



If the instrument fails this check, it must be repaired before any distance 
measurements can be made with it. 




2 . Connect the 3-foot precision cable to the front-panel CABLE connector. The 
display should now look like Figure B-2. 




3 . Using the POSITION control, measure the distance to the rising edge of the 
waveform at the open end of the cable. The distance shown on the display 
distance window (upper right corner of the LCD) should be from 2.87 to 3.13 
feet (0.875 to 0.954 m). 



2-2 



1502B MTDR Service Manual 



Operator Performance Checks 




4. Remove the 3-foot cable and connect the 50Q terminator. 

5. Change the DIST/DIV to 200 ft/div (50 m/div) 

6. Turn the POSITION control clockwise until the distance window shows a 
distance greater than 2,000 feet (> 600 m). The waveform should be a flat line 
from the pulse to this point. 




Figure 2-4: Flat-Line Display Out to 50,000+ Feet 

7. Turn the ^ POSITION control counterclockwise until the distance window 
shows a distance less than 10.000 feet (< 3.1 m). 

8. Set the DIST/DIV control to . 1 ft/div (0.025 m/div). 

9. Turn the ^ POSITION control counterclockwise until the distance window 
shows a distance of -2.000 feet (-0.611 m). 



1502B MTDR Service Manual 



2-3 



Operator Performance Checks 



2. Vertical Position 
(Offset) Check 




Figure 2-5: Flat-Line Display at -2.000 ft 

This last step has set up the instrument for the next check. 



If the instrument fails this test, it can be used, but should be serviced when possible. 
Not all of the waveforms will be viewable at all gain settings. 



1. Using the y POSITION control, verify that the entire waveform can be moved 
to the very top of the display (off the graticule area). 



ac 










-2.000 ft 




















.... 













































































































Figure 2-6: Waveform Off the Top of the Display 



\ 

Waveform 
off display 



2. Using the y POSITION control, verify that the entire waveform can be moved 
to the very bottom of the display (to the bottom graticule line). 



2-4 



1502B MTDR Service Manual 



Operator Performance Checks 



3. Noise Check 



Waveform 

/ 



If the instrument fails this check, it can still be usable for measurements of large 
faults that do not require a lot of gain, but send the instrument to be serviced when 
possible. A great deal of noise reduction can be made using the NOISE FILTER 
control. 

1. Adjust the POSITION control to obtain 100.000 ft in the distance window. 



ac 






100.000 ft 




1 . . . . 














1 






















,, ; : 































































Figure 2-8: Waveform with Gain at 5.00 mp/div 

2. Using the 0 POSITION control and VERT SCALE control, set the gain to 5.00 
mp/div. Keep the waveform centered vertically in the display. 

3. Press MENU. 

4. Using the 0 POSITION control, select Diagnostics Menu. 

5. Press MENU again. 

6. Using the 0 POSITION control, select Service Diagnostic Menu. 

7. Press MENU again. 

8. Using the 0 POSITION control, select Noise Diagnostics. 

9 . Press MENU again and follow the instructions on the display. 




Figure 2-7: Waveform at the Bottom of the Display 



1502B MTDR Service Manual 



2-5 



Operator Performance Checks 



4. Offset/Gain Check 



5. Sampling Efficiency 
Check 



6. Aberrations Check 



10 . Exit from Noise Diagnostics , but do not exit from the Service Diagnostic Menu 
yet. 



If the instrument fails this check, it should not be used for loss or impedance 
measurements. Send it to be serviced when possible. 

1. In the Service Diagnostic Menu , select the Offset/Gain Diagnostic and follow 
the directions on the display. 



NOTE. Occasionally, the instrument might not pass the 48 dB step. This is no cause 
for alarm. If the remainder of the steps do not fail, proceed as normal. Refer to 
Chapter 6 of this manual. 



There are three screens of data presented in this diagnostic. The Pass/Fail level is 
3% for any single gain setting tested. 

2. Exit from Offset/Gain Diagnostic , but do not leave the Service Diagnostic 
Menu yet. 



If the instrument fails this check, the waveforms might not look normal. If the 
efficiency is more than 100%, the waveforms will appear noisy. If the efficiency is 
below the lower limit, the waveform will take longer (more pixels) to move from 
the bottom to the top of the reflected pulse. This smoothing effect might completely 
hide some faults that would normally only be one or two pixels wide on the display. 

1. In the Service Diagnostic Menu , select Sampling Efficiency and follow the 
directions on the screen. 

2. When done with the test, press the MENU button repeatedly until the instrument 
returns to normal operation. 



If the aberrations are out of specification, the ohms-at-cursor function might be less 
accurate than specified. 

1. Connect the 50Q precision terminator to the front-panel CABLE connector. 

2. Set the DIST/DIV control to 5 ft/div (1 m/div). 

3. Increase the VERT SCALE control to 50 mp/div. 

4 . Using the 0 POSITION control, move the top of the pulse to the center graticule 
line. 



2-6 



1502B MTDR Service Manual 



Operator Performance Checks 



ac 








-2.000 ft 




















.... 




















IL 



































































































Figure 2-9: Top of Pulse on Center Graticule 



5. Set the DIST/DIV control to 0.2 ft/div (0.05 m/div). 

6. Turn the <l> POSITION control clockwise until the rising edge of the incident 
pulse is in the left-most major division on the display. 




Figure 2-10: Rising Edge of Incident Pulse in Left-most Major Division 



7. Using the <l> POSITION control, move the cursor back to 0.000 ft (0.00 m). 



All the aberrations, except the one under the cursor (see Figure 2-11, next page), 
must be within one division of the center graticule line from out to 10 feet past 
the rising edge of the pulse. 



To verify distances past the right edge of the display, scroll along the waveform 
by turning the ^ POSITION control clockwise. 



1502B MTDR Service Manual 



2-7 



Operator Performance Checks 



7. Risetime Check 




Figure 2-11 : Waveform Centered, Cursor at 0.000 ft 



If the risetime is out of specification, it might be difficult to make accurate 
short-distance measurements near the front panel. 

1. Set the 1502B front-panel controls: 

NOISE FILTER 1 avg 

VERT SCALE 500 mp/div 

DIST/DIV 0.2 ft/div (0.05 m) 

Vp .99 

2. Using the <1> POSITION control, move the incident pulse to the center of the 
display as shown below. 




3. Turn the VERT SCALE control clockwise until the leading edge of the incident 
pulse is five major divisions high (about 205 mp). 

4. Position the waveform so that it is centered about the middle graticule line. 



2-8 



1502B MTDR Service Manual 



Operator Performance Checks 



8. Jitter Check 




Crosses 

Lowest 

Point 



Figure 2-13: Cursor on Lowest Major Graticule that Rising Edge crosses 



5. Using the <ll> POSITION control, and noting the distances displayed, verify that 
the distance between the points where the leading edge crosses the highest and 
lowest major graticule lines is less than or equal to 0.096 feet (0.029 m). 




Crosses 

Highest 

Point 



Figure 2-14: Cursor on Highest Major Graticule that Rising Edge crosses 

In the above example, the distances are -0.848 feet and -0.768 feet. The difference 
between these two measurements is 0.080 feet, which is well within specification. 



Jitter is the uncertainty in the timebase. Its main effect is that the waveform appears 
to move back and forth a very small amount. If the jitter is too great, it will affect 
the repeatability of very precise distance measurements. 



1. Set the VERT SCALE less than or equal to 1.0 mr/div. 

2. Watch the leading edge of the pulse move and verify that this movement is less 
than five pixels, or < 0.02 ft (0.006 m). 



1502B MTDR Service Manual 



2-9 



Operator Performance Checks 



Conclusions 



? 

? 

? 



ac 










-1 .624 ft ! 




















: 










































































































i 



Jitter 



Figure 2-15: Jitter Apparent on Leading Edge of Incident Pulse 

Using the Max Hold function (accessed in the Setup Menu , Acquisition Control) can 
simplify your observation of jitter. Max Hold allows you to observe the accumulated 
jitter without having to stare continuously at the display. 



? 

? 

? 



ac 










-1 .624 ft ! 






















.... 


































































































































i 



Accumulated 

Jitter 



Figure 2-16: Jitter Captured Using Max Hold 

If the instrument failed Jitter or Risetime checks, it is probably still adequate for all 
but extremely precise distance measurements. If it failed the Horizontal Scale check, 
you should not use the instrument until the cause of the failure has been identified 
and corrected. 

All of the previous checks only test the major functional blocks of the instrument 
that could prevent you from being able to make measurements. It is possible for the 
front-panel controls or the LCD to have problems that would interfere with 
controlling or displaying measurements. Most problems of this type would become 
evident as you perform the checks. If you suspect a problem of this nature, you 
should have the instrument checked by a qualified service technician, using the 
diagnostics in the 1502B Service Manual. 

If the instrument passed all of the previous checks, it is ready for use. 



2-10 



1502B MTDR Service Manual 



Specifications 



The tables in this chapter list the characteristics and features that apply to this 
instrument after it has had a warm-up period of at least five minutes. 

The Performance Requirement column describes the limits of the Characteristic. 
Supplemental Information describes features and typical values or other helpful 
information. 



Electrical Characteristics 



Characteristic 


Performance Requirement 


Supplemental Information 


Excitation Pulse 
Reflected Pulse 


<200 ps (0.096 feet) 


Vp set to 0.99; 10 to 90%, into a precision short 


Aberrations 


± 5% peak within 0 to 10 feet after rise 
± 0.5% peak beyond 10 feet 


Excluding front panel aberrations 


J itter 


< 0.02 feet ( < 40 ps) p-p Horz scale 0.1 ft/div 

< 0.2 feet ( < 400 ps) p-p Horz scale 1 ft/div 


Vp set to 0.99, DIST/DIV set to 0.1 ft/div 
At 23.4 feet to 46.8 feet, jitter is <0.04 feet. 


Output Impedance 


50Q ±2% 


After risetime stabilizes into 50Q termination 


Pulse Amplitude 




300 mV nominal into 50Q load 


Pulse Width 




25 ps nominal 


Pulse Repetition Time 




200 ps nominal 


Vertical 

Scales 


0.5 mp/div to 500 mp/div, 


>240 values, includes 1, 2, 5 sequences 


Accuracy 


Within ±3% of full scale 




Set Adj 


Set incident pulse within 3% 


Combined with VERT SCALE control 


Vertical Position 




Any waveform point is moveable to center 
screen 


Displayed Noise 


± 5 mp peak or less, filter set to 1 
± 2 mp peak or less, filter set to 8 




Distance Cursor 
Resolution 




l/25th of 1 major division 


Cursor Readout 
Range 




-2 ft to >2,000 ft 


Resolution 




0.004 ft 


Distance Measurement 
Accuracy 


1.6 inches or ± 1% of distance measured, 
whichever is greater 


For cables with Vp =0.66 
For delta mode measurements 
Error <0.5% for distance >27 ft 
Error <1.0% for distance >14 ft 
Error <2.0% for distance >7 ft 
Error < 10% for distance >1.5 ft 



(continued next page) 



1502B MTDR Service Manual 



3-1 




Specifications 



Characteristic 


Performance Requirement 


Supplemental Information 


CursorOhms Readout 
Range 




1 Q to 1 kQ 


Resolution 




3 significant digits 


Accuracy 




± 10% with serial cable impedance 
correction (relative impedance 
measurements ±2%) 


Horizontal 

Scales 

Range 




11 values, 1, 2, 5 sequence 

0.1 ft/div to 200 ft/div (0.025 m/div to 50 m/div) 

1ft to 2, 000 ft (2. 5 m to 500 m) 


Horizontal Position 




Any distance to full scale can be moved on 
screen 


Vp 

Range 




Propagation velocity relative to air 
0.30 to 0.99 


Resolution 




0.01 


Accuracy 


Within ±1% 


Included in total timebase error tolerance 


Custom Option Port 




Tektronix Chart Recorders YT-1 and YT-1S are 
designed to operate with the 1502B. Produces a 
high resolution thermal dot matrix recording of 
waveform and switch values. 


Line Voltage 


115 VAC (90 to 132 VAC) 45 to 440 Hz, or 
230 VAC (180 to 250 VAC) 45 to 440 Hz, or 
12 VDC through battery pack connector 


Fused at 0.3 A 
Fused at 0.15 A 


Battery Pack 
Operation 


5 hours minimum, 20 chart recordings maximum 


+15° C to +25° C charge and discharge temp, 
LCD backlight off. Operation of instrument with 
backlight on or at temps below +10° C will 
degrade battery operation specification 


Full Charge Time 




20 hours maximum 


Overcharge Protection 




Limited to 10 days continuous charge. Battery 
will charge whenever instrument is plugged in. 
Battery can be removed during AC operation. 


Discharge Protection 




Operation terminates prior to cell reversal 


Charge Capacity 




2 Amp-hours typical 


Charge Indicator 




Bat/low will be indicated on LCD when capacity 
reaches approximately 10% 



3-2 



1502B MTDR Service Manual 



Specifications 



Environmental Characteristics 



Characteristic 


Performance Requirement 


Supplemental Information 


Temperature 

Operating 


-10°C to+55°C 


Battery capacity reduced at other than +15°C to 
+25°C 


Non-operating 


-62° C to +85° C 


With battery pack removed. Storage temp with 
battery pack in is -20° C to +55° C. Contents 
on non-volatile memory (stored waveform) might 
be lost at temps below -40° C. 


Humidity 


to 100% 


Internal desiccant 


Altitude 

Operating 


to 15,000 ft 


MIL-T-28800C, Class 3 


Non-operating 


to 40,000 ft 




Vibration 


5 to 15 Hz, 0.06 inch p-p 
15 to 25 Hz, 0.04 inch p-p 
25 to 55 Hz, 0.013 inch p-p 


MIL-T-28800C, Class 3 


Shock, Mechanical 
Pulse 


30 g, 11 ms 1/2 sine wave, total of 18 shocks 


MIL-T-28800C, Class 3 


Bench Handling 




M IL- STD-810, Method 516, Procedure V 


Operating 


4 drops each face at 4 inches or 45 degrees 
with opposite edge as pivot 


Cabinet on, front cover off 


Non-operating 


4 drops each face at 4 inches or 45 degrees 
with opposite edge as pivot. Satisfactory opera- 
tion after drops. 


Cabinet off, front cover off 


Loose Cargo Bounce 


1 inch double-amplitude orbital path at 5 Hz, 6 
faces 


M IL- STD-810, Method 514, Procedure XI, 
Part 2 


Water Resistance 
Operating 


Splash-proof and drip-proof 


MIL-T-28800C, Style A 
Front cover off 


Non-operating 


Watertight with 3 feet of water above top of case 


Front cover on 


Salt Atmosphere 


Withstand 48 hours, 20% solution without 
corrosion 




Sand and Dust 


Operates after test with cover on, non-operating 


M IL- STD-810, Method 510, Procedure 1 


Washability 


Capable of being washed 




Fungus Inert 


Materials are fungus inert 





(continued next page) 



1502B MTDR Service Manual 



3-3 



Specifications 



Characteristic 


Performance Requirement 


Supplemental Information 


Electromagnetic Compatibility 


VDE 0871 Class B 






MIL-T-28800C 
MIL-STD-461A notice 4(EL) 


C E 02, CE04, CS02, CS06, RE02, 
RE02.1 






RS03, RS03.1 from 14 kHz to 10 
GHz 


Radiated Susceptibility 


MIL-STD-461A notice 4(EL), method MIL-STD-462 notice 3 
for RS03 and RS03.1 


Limited to 1 V/m (greater than 1 
GHz, displayed noise characteristics 
performance shall be: ± 10 mp peak 
or less, with 50Q termination con- 
nected to RF input (16 averages)). 



Physical Characteristics 



Characteristic 


Description 


Weight 


without cover 


14.25 lbs (6.46 kg) 




with cover 


15.75 lbs (7.14 kg) 




with cover, chart recorder, and battery pack 


19.75 lbs (8.96 kg) 


Shipping Weight 
domestic 


25.5 lbs (11.57 kg) 




export 


25.5 lbs (11.57 kg) 


Height 


5.0 inches (127 mm) 


Width 


with handle 


12.4 inches (315 mm) 




without handle 


11.8 inches (300 mm) 


Depth 


with cover on 


16.5 inches (436 mm) 




with handle extended to front 


18.7 inches (490 mm) 



3-4 



1502B MTDR Service Manual 



Options and Accessories 



The following options are available for the 1502B MTDR: 



Option 03: Battery Pack 

Option 03 instruments come equipped with a rechargeable nickel-cadmium battery 
pack. 



Battery Pack Removal and 
Replacement 




CAUTION. Read the instructions in the front of this manual concerning safety 
precautions necessary when charging, removing, or servicing the battery pack. 



1. Loosen the two knurled screws on the battery pack and pull back to remove from 
the rear panel of the instrument. 

2. Check that the battery pack banana sockets are aligned correctly with the battery 
pack port banana plugs. Push the battery pack directly into the compartment and 
tighten the two screws finger tight. 

3. If removing the battery for any length of time, seal the battery pack port with 
the battery port cover. This will help seal the instrument from dirt and moisture. 



Option 04: YT-1 Chart Recorder 

Option 04 instruments come equipped with a chart printer. Refer to the YT-1/ YT-1 S 
Chart Recorder Instruction Manual that comes with this option for instructions on 
operation, paper replacement, and maintenance. 



Option 05: Metric Default 

Option 05 instruments will power up in the metric measurements mode. Standard 
measurements may be selected from the menu, but metric will be the default. 



1502B MTDR Service Manual 



4-1 




Options and Accessories 



Option 07: YT-1S Chart Recorder 

Option 07 instruments come equipped with a splashproof chart printer. Refer to the 
YT-1/ YT-1S Chart Recorder Instruction Manual that comes with this option for 
instructions on operation, paper replacement, and maintenance. 



Power Cord Options 



The following power cord options are available for the 1502B TDR. Note that these 
options require inserting a 0.15 A fuse in the rear panel fuse holder. 



NOTE. The only power cord rated for outdoor use is the standard cord included with 
the instrument (unless otherwise specified). All other optional power cords are 
rated for indoor use only. 



Option Al: 220 VAC, 16 A, Universal Europe 161-0066-09 

Option A2: 240 VAC, 13 A, United Kingdom 161-0066-10 

Option A3: 240 VAC, 10 A, Australia 161-0066-11 

Option A4: 240 VAC, 15 A, North America 161-0066-12 

Option A5: 240 VAC, 6 A, Switzerland 161-0154-00 



Accessories 

Standard Accessories 

■ Replacement Fuse (AC line fuse, 115 VAC) 159-0029-01 

■ Replacement Fuse (AC line fuse, 230 VAC) 159-0054-00 

■ Power Cord (outdoor rated) 161-0228-00 

■ Option Port Cover Assembly 200-3737-00 

■ Precision 50Q Test Cable (S/N >B021135) 012-1350-00 

■ 50Q BNC Terminator 011-0123-00 

■ BNC Connector, female-to-female 103-0028-00 

■ Slide Rule Calculator 003-0700-00 

■ Slide Application Note (bound in this manual) 062-8344-xx 

■ Accessory Pouch 016-0814-00 

■ Operator Manual 070-6266-xx 



4-2 



1502B MTDR Service Manual 



Options and Accessories 



Optional Accessories 



■ Service Manual 070-6267-xx 

■ Battery Pack 016-0813-00 

■ Chart Recorder, YT-1S 119-3616-00 

■ Chart Paper, single roll 006-7647-00 

■ Chart Paper, 25-roll pack 006-7677-00 

■ Chart Paper, 100-roll pack 006-7681-00 

■ Connector, BNC male to BNC male 103-0029-00 

■ Connector, BNC female to Alligator Clip (S/N > B025708) . . 013-0261-00 

■ Connector, BNC female to Hook-tip Leads 013-0076-01 

■ Connector, BNC female to Dual Banana Plug 103-0090-00 

■ Connector, BNC male to Dual Binding Post 103-0035-00 

■ Connector, BNC male to N female 103-0058-00 

■ Connector, BNC female to N male 103-0045-00 

■ Connector, BNC female to UHF male 103-0015-00 

■ Connector, BNC female to UHF female 103-0032-00 

■ Connector, BNC female to Type F male 103-0158-00 

■ Connector, BNC male to Type F female 013-0126-00 

■ Connector, BNC female to GR 017-0063-00 

■ Connector, BNC male to GR 017-0064-00 

■ Terminator, 75Q BNC 011-0102-00 

■ Adapter, Direct Current 015-0327-00 

■ * Adapter, 50/750 017-0091-00 

■ * Adapter, 50/930 017-0092-00 

■ * Adapter, 50/1250 017-0090-00 



* . These adapters should be purchased if GR connectors (017-0063-00 and/or 
017-0064—00) are purchased. 



1502B MTDR Service Manual 



4-3 



Options and Accessories 



4-4 



1502B MTDR Service Manual 



WARNING 



The following servicing instructions are for use only by qualified 
personnel. To avoid injury, do not perform any servicing other than 
that stated in the operating instructions unless you are qualified to do 
so. Refer to all Safety Summaries before performing any service. 



Circuit Descriptions 



Introduction 



This chapter describes how the instrument works. First is a circuit overview and how 
it relates to the block diagram (Figure 5-1, next page). Following that are the 
separate sections of the instrument, discussed in detail. 



The 1502B uses time-domain reflectometry techniques to detect and display the 
impedance characteristics of a metallic cable from one end of the cable. This is 
accomplished by applying a rapidly rising step to the cable and monitoring the 
resulting voltage over a period of time. If the cable has a known propagation 
velocity, the time delay to a particular reflection can be interpreted in cable distance. 
Amplitude of the reflected voltage is a function of the cable impedance and the 
impedance of the termination relative to the cable leading to it. The amplitude can 
be interpreted in rho or dB. Rho (p) is a convenient impedance function defined as 
the voltage reflection coefficient. It is the ratio between the incident step and the 
reflected step. For the simple case of a cable with a resistive load: 



R l -Z 0 

P = — — 

R|_ + Zq 

Where: 

Rl is the load impedance, and 
Zq is the characteristic impedance. 

The 1502B instrument is comprised of several subsections, as shown in the block 
diagram (Figure 5-1). These are organized as a processor system, which controls 
several peripheral circuits to achieve overall instrument performance. 

The processor system reads the front-panel control settings to determine the cable 
information that you selected for viewing. Distance settings are converted to 
equivalent time values and loaded into the timebase circuits. 

The timebase generates repetitive strobe signals to trigger the driver/sampler 
circuits. Pulse strobes cause a step to be applied to the cable under test. Sample 
strobes causes a single sample of the cable voltage to be taken during a very short 
interval. The timebase precisely controls the time delay of the sample strobe relative 
to the pulse strobe. When many sequential samples are recombined, a replica of the 
cable voltage is formed. This sampling technique allows extremely rapid repetitive 
waveforms to be viewed in detail. 



1502B MTDR Service Manual 



5-1 




Circuit Descriptions 



(JJ) Cable 



Front Panel 



Drivers 



LCD 



Controls, LCD Bias 
and temp, compensation 



Digital Bus 



Main Board 



CPU 



Z80 



RAM 



ROM 



Decoding 



Option Port 



Power Supply 



■j 



— I 



Front End 



Driver 



Sampler 



Hybrid 



J L 



Timebase 



Digital 



Analog 



Signal Processing 



Offset - ► Gain 



A/D converter 



Power Bus 





- - - ► 


Control 


- - - 




AC to DC 




A 




DC to DC 


Converter 




Battery 




Converter 



Figure 5-1 : System Block Diagram 



5-2 



1502B MTDR Service Manual 



Circuit Descriptions 



Referring to the waveforms in Figure 5-2, cable voltage waveforms are shown at 
the top. Each step is from the pulse generator and all steps are identical. At time 
delays (t n , t n+ i, t n + 2 , etc.) after the steps begin, a sample of the step amplitude is 
taken. Each of these samples is digitized and stored in the processor until sufficient 
points are accumulated to define the entire period of interest. The samples are then 
processed and displayed at a much slower rate, forming the recombined waveform 
as shown. This process allows the presentation of waveforms too rapidly to be 
viewed directly. 




Voltage samples from the driver/sampler are combined with a vertical position 
voltage derived from the front-panel control, then amplified. The amplifier gain is 
programmed by the processor to give the selected vertical sensitivity. Each 
amplified sample voltage is then digitized by an analog-to-digital converter and 
stored in the processor memory. 

When the processor has accumulated sufficient samples (251) to form the desired 
waveform, the samples are formatted. This formatted data is then transferred to the 
display memory. The display logic routes the data to each pixel of the LCD, where 
each digital data bit determines whether or not a particular pixel is turned on or off. 

Between each waveform, samples are taken at the cursor location for the “ohms at 
cursor” function, and at the leading edge of the incident step for use by the timebase 
correction circuit. 

Cursor and readout display data is determined by the processor and combined with 
the formatted sample waveform before it is sent to the display. 



1502B MTDR Service Manual 



5-3 



Circuit Descriptions 



Power Supply 



Introduction The power supply consists of the following: 

■ Primary Circuit 

■ Pre-regulator 

■ Battery Charger 

■ Deep Discharge Protection 

■ Port-regulator 

■ DC-to-DC Converters 

The power supply converts either 115/230 VAC line power, or takes power from a 
nickel-cadmium battery pack, and provides the instrument with regulated DC 
voltages. A block diagram of the power supply is shown in Figure 5-3. 



Instr. 




Figure 5-3: Power Supply Block Diagram 



Single-phase AC line voltage is applied to the power supply module through a 
power plug with internal EMI filter. The filtered line voltage is immediately fused, 
routed through a line selector switch and applied to a stepdown transformer. The 
transformer secondary voltage is rectified and power switched to power the post 
regulator. 



5-4 



1502B MTDR Service Manual 



Circuit Descriptions 



Primary Circuit 



A switching pre-regulator reduces this voltage to +15.8 VDC and is used to power 
the battery charger. This voltage is also processed through a rectifier and power 
switch to power the post-regulator. 

If a battery pack is installed, the battery charger operates as a current source to 
provide a constant charging current. Voltage limiting circuits in the charger prevent 
battery overcharge by reducing the charge current as the battery voltages approaches 
+12.5 VDC. 

The battery pack consists of nine nickel-cadmium C-size cells, connected in series. 
This combination provides a terminal voltage of 10 to 12.5 VDC, with a nominal 
capacity of up to 2.0 Amp-Hours. It also is connected through a rectifier to the 
instrument’s power switch and post-regulator. 

When the power switch is closed, an FET power transistor is momentarily turned 
on by the deep discharge protection circuit. If the voltage to the post-regulator rises 
to +9.7 VDC or greater, the transistor switch remains on. If at any time, the voltage 
drops below +9.7 VDC, the transistor turns off and the power switch must be 
recycled to restart the instrument. This operation prevents discharge of the battery 
pack below +10 VDC. Such a discharge could cause a reverse charge in a weak cell, 
resulting in permanent cell damage. 

The post-regulator is a boost switching regulator that increases its input voltage to 
a constant +16.2 VDC output. This voltage is supplied directly to the processor for 
large loads, such as the display heater, electroluminescent backlight, and options 
port. The post-regulator also supplies a DC-to-DC converter that generates 
± 5 VDC and ±15 VDC for use in the instrument. 

Status signals indicating whether the instrument is running on AC line voltage or 
the battery pack, and if the battery pack is approaching turn-off level, are supplied 
to the instrument by the deep-discharge protection circuits. 



The AC line power is received by the connector in the EMI filter (FL1). This filter 
prevents high frequency signals generated in the instrument from being conducted 
back to the AC power line. The line voltage is fused (F101) and switched (S201) 
to the primary step-down transformer (T201). Both the switch and the fuse can be 
accessed from the outside of the instrument via covers on the rear of the cabinet. 

The primary of T201 is wound in two identical sections. These sections are 
connected by S201 (in parallel for 110 VAC operation or in series for 220 VAC 
operation). The secondary of T201 is connected by a short two- wire cable to the 
Power Supply Board. The MOV (R101), across one of T201’s primaries, protects 
the power supply if 220 VAC is applied while S2011 is in the 110 VAC position. 
Fuse F101 will open in this event. 



1502B MTDR Service Manual 



5-5 



Circuit Descriptions 



Pre-Regulator 



Battery Charger 



Deep Discharge 
Protection 



The secondary voltage is full- wave rectified by CR1010 and filtered by capacitor 
C1010. The large value of this capacitor allows it to supply energy to the instrument 
between half cycles of the line voltage. 

Integrated circuit U1010 is a pulse- width modulator switching regulator controller. 
It oscillates at approximately 70 kHz and provides drive pulses to switching 
transistors Q1010 and Q1011. The output pulses from these transistors are filtered 
to DC by flyback rectifier CR2010, choke L1010, and capacitors C2010 and C2012. 
The resulting +16.6 VDC is fed back to the regulator U1010 by voltage divider 
R1016 and R1015. It is then compared to a +2.5 VDC reference voltage from, 
U101 1 . To increase the output voltage, U1010 increases the pulse width of the drive 
to Q 1 0 1 0 and Q 1 0 1 1 . To reduce the output voltage, U 1 0 1 0 decreases the pulse width 
to Q1010 and Q1011. This assures that a constant +16.6 VDC is maintained. 

Resistor R1010 acts as a current sensing shunt in the pre-regulator return line. In the 
event that a circuit fault draws excess current, the voltage developed across R1010 
(and filtered byR1011,R1012, and C1011) will cause U1010 to reduce the pulse 
width of the pre-regulator. This protects the pre-regulator from damage due to 
overload. 



The battery charger consists of a linear regulator integrated circuit, U2010, and 
associated components. U2010 is connected as a current source, drawing current 
from the +15.8 VDC and supplying it to the battery through T2012. The voltage 
drop across T2012 is fed back to U2010 through diode CR2014 to control charging 
current at a nominal 150 mA. Diode CR2013 and voltage divider R2010 and R201 1 
provide a voltage clamp to U2010’s feedback terminal to limit the maximum voltage 
that can be applied to the battery through CR2015. As the voltage R2012 and 
CR2015 approaches the clamp voltage, battery charging current is gradually 
reduced to trickle charge. 

Rectifier CR2015 prevents battery discharge through the charger when AC line 
voltage is not present. Rectifier CR2012 allows the battery pack to power the 
instrument when AC power is not present. 



Pre-regulator or battery voltage is applied to Q201 1 and Q2012 when the instrument 
power switch is pulled on. The rising voltage causes Q2011 and Q2012 to turn on 
due to the momentary low gate voltage while C2011 is charging. During this time, 
voltage comparator U1020A compares the switched voltage to a +2.5 VDC 
reference from U1022. If the voltage is greater than +9.7 VDC, U1020A turns on, 
drawing current through Q2010 and R2015 to keep the gates of Q2011 and Q2012 
near ground and the transistors turned on. If the voltage is less than +9.7 VDC (or 
drops to that value later), U 1020 A and Q2010 turn off, allowing C2011 to charge 
to the input voltage and turn off Q2011 and Q2012. When turned off, the deep 
discharge protection circuit limits current drawn from the battery pack to only a few 
microamperes. 



5-6 



1502B MTDR Service Manual 



Circuit Descriptions 



Post-Regulator 



DC-to-DC Converter 



Processor System 

Introduction 



The post-regulator receives from +9.7 to +15.5 VDC and boosts it to +16.2 VDC 
by switching Q2022 on and off with a pulse- width modulated signal. When Q2022 
is turned on, input voltage is applied across choke L2020, causing the current in 
L2020 to increase. When Q2022 is turned off, the stored energy in L2020 will cause 
the current to continue flowing through CR2021 to filter capacitor C2025. Due to 
its stored energy, the voltage developed across L2020 adds to the input voltage, 
allowing C2025 to be charged to a voltage greater than the input. 

The switching of Q2022 is controlled by pulse- width modulator U1023. The 
post-regulator output voltage is fed back to U1023 through R1025 and R1024 and 
compared to the +2.5 VDC reference from U 1022. Low output voltage causes wider 
pulses to be supplied to Q2022, storing more energy in L2020 during each pulse. 
This results in a higher output voltage. High output voltage, however, reduces pulse 
width and reverses the preceding process. 

U1023 oscillates at approximately 80 kHz and supplies a synchronizing signal to 
the pre-regulator at that frequency when the instrument is operating on AC power. 
This raises the pre-regulator frequency to the same 80 kHz. This synchronization 
eliminates beat frequency interference between the two regulators. 

The synchronizing signal from U1023 is also supplied to Q2021, where it is 
amplified to CMOS levels and buffered by gate U2030A. The signal is then used 
to clock flip-flop U1024B to produce a 40 kHz square wave output at Q and Q. These 
square waves are buffered by other U2030 inverters and used to drive DC-to-DC 
transistors Q2030 and Q2031. 



Transistors Q2030 and Q2031 apply push-pull power to the primary of T1030 at 
40 kHz by switching the +16.2 VDC alternately between the primary windings. The 
resulting transformer secondary voltages are rectified and filtered by CR1034, 
C1032, C1033, and C1034 to produce +15 VDC and -15 VDC. Other secondary 
voltages are rectified and filtered by CR1030, CR1031, CR1032, CR1033, C1030, 
Cl 031, and Cl 037 to produce +5 VDC and -5 VDC. 

Diodes CR203 1 and CR2030 rectify the primary voltage and clamp it to the voltage 
level that is across C2031. This prevents voltage transients caused by the rapid 
switching of Q2030 and Q2031 and prevents the leakage inductance of T1030’s 
primary from creating excessive voltage stress. R2030 provides a discharge path 
from C2031. T1031 and Cl 036 provide additional filtering of the +16 VDC supply. 



The processor system consists of the following: 

■ Microprocessor 

■ Address Decoding and Memory 

■ Interrupt Logic 



1502B MTDR Service Manual 



5-7 



Circuit Descriptions 



Microprocessor 



The processor system provides control and calculation functions for the instrument. 
A block diagram of the processor system is shown in Figure 5-4. 

An eight-bit microprocessor, clocked at 5 MHz, provides the processing capability 
in a bus-organized system. Instructions are read from the program memory EPROM 
and executed by the microprocessor to accomplish essentially all instrument 
functions. Random access memory is connected to the microprocessor through its 
data and address busses, allowing it to store and retrieve control, video, and display 
data, as required. 



5 MHz 
CLOCK 



c n 
c n 

LU 

cc 

Q 

o 

< 




Figure 5-4: Processor Block Diagram 

The processor communicates with all other instrument circuits via the address, data, 
and select signals, and receives requests for service from those circuits via the 
interrupt and status signals. Select signals are generated in address decoding circuits 
under control of the processor and used to read or write data from a circuit, or to 
trigger a circuit function. Interrupts from those circuits are combined in the interrupt 
logic to generate an interrupt request to the microprocessor. The processor responds 
by reading a data word from this logic to determine the source of the interrupt, or 
status data, and then performs the required service routine. 



The microprocessor, U1023, is a single chip processor using Z80 architecture 
constructed in high-speed CMOS logic. Each data word, or byte, is eight bits wide 
and the microprocessor has a 16-bit address capability, allowing it to address up to 
65,536 memory locations. The processor’s 5 MHz clock is derived from a crystal 
oscillator in the timebase circuits. 



5-8 



1502B MTDR Service Manual 



Circuit Descriptions 





When +5 VDC power is applied to C1030 and R1032, the rising voltage 
momentarily applies a positive signal to the input of gate U 103 IB. The resulting 
negative pulse at the gate output is supplied to U1023’s reset input, causing the 
microprocessor to start at the beginning of its programmed routine each time power 
is applied. 


Address Decoding and 
Memory 


The 16-bit address space of Z80 processor U1023 is divided into five primary areas. 
They are: 

■ Program Memory (EPROM) space 

■ RAM space 

■ Non-volatile RAM space 

■ Display RAM space 

■ Enable and Select Signal space 


Program Memory 
(EPROM) 


The program memory is stored in 64-kilobyte (kb) EPROM U2020, which is 
divided into two 32-kb bank-switched halves. Both halves occupy locations 
OOOOH to 7FFFH in the processor’s address space. The most significant address 
bit on the EPROM, which determines which bank is addressed, is set by flip-flop 
U2030A. This bank- switching flip-flop can be toggled by the processor with two 
select lines, decoded in the enable and select signal address space. The select signal 
for the EPROM is generated by combined address line A15 with the MREQ signal 
in U1045A. Whenever the processor addresses a location where A15 is not set, the 
program memory will be selected to place data on the bus. 


RAM 


The first RAM is eight-kilobyte memory U 1021, selected by a signal generated by 
a 1 -of -8 decoder, U 1022. This decoder operates on the three most significant address 
bits (A 15 , A 14 , A 13 ) in combination with MREQ. Each of its decodes represents a 
selection of a particular Vs th of addressable locations. The first four decode signals 
are not used because they are located in the program memory space. The fifth decode 
is the select signal for the first RAM, occupying locations 8 OOOH to 9FFFH. 


Non-Volatile RAM Space 


The second RAM is also an 8 -kb memory, U1020, made non-volatile by lithium 
battery BT1010 and non-volatile memory controller U1010. The select signal for 
this RAM is generated similarly to that for the first RAM with the sixth Vs th decode 
of U1022. This decode occupies AOOOH to BFFFH. 


Display RAM Space 


The display RAM is also an 8 -kb memory, U1040, located in the display module. 
It is selected by the seventh decode of U1022. It occupies locations COOOH to 
DFFFH. 


Enable and Select Signal 
Space 


The remaining addressable space is used to generate enable, select, or trigger 
signals, which read, write, and control other circuits of the instrument. The eighth 



1502B MTDR Service Manual 5-9 



Circuit Descriptions 



Additional Decoding 



Interrupt Logic 



Option Port Interface 

Introduction 



Vs th decode signal of U1022 is used to enable four other l-of-8 decoders: U2021, 
U2022, U2024, and U2026. These four decoders are further selected by the four 
combinations of A12 and An and operate on A10, A9, and Ag to generate the enable, 
select, and trigger signals CSOO through CS3 1 . These occupy the remaining address 
space, locations EOOOH to FFFFH. 

An automatic wait state is inserted for all circuits selected by U2022. The wait state 
is used by the processor to compensate for the slow access times of U2041, U2046, 
and U4020 on the Main Board; U2023 on the Front Panel Board; and U2040 on the 
display module. The wait request is generated by U 1041. 

The select signals from U2024 are also modified through U1043B by a 200-ns pulse. 
This pulse is created from gates U1042B, U 103 1C, U2040C, and J-K flip-flop 
U2033A. This circuit creates a write pulse that ends prior to the completion of the 
processor bus cycle, thus meeting data hold time requirements for some selected 
ICs. 



The most significant address bit on the EPROM is set or reset by bank- switching 
flip-flop U2023A. Another control signal, heat disable, is generated by a similar 
flip-flop, U2023B. This is also toggled by two select lines. 



The interrupt logic consists of an eight-bit tri-state buffer, U1032, and gates U1030 
and U1031D. Six interrupt requests signals are logically OR’d by U1030, then 
inverted by U103 ID and applied to the microprocessor interrupt request input. Five 
of the interrupts are received from the video ADC, the digital timebase, a real-time 
counter, the front panel control ADC, and from the Option Port connector. The sixth 
interrupt input is unused. 

The six interrupt requests and two power status signals are connected to pull-up 
resistors R1033 and the inputs of buffer U 1032. When the microprocessor responds 
to an interrupt request, it selects U1032, allowing the eight inputs to that device to 
be placed on the data bus for reading. 

The processor system outputs six control signals to the Driver/Sampler module. 
These signals are loaded from the data bus into latch U3010 by a select signal from 
the address decoder. These signals are used by the 1502B Driver/Sampler and the 
Option 06 adapter (if equipped). 



The option port interface consists of the following: 

■ Supply Controller 

■ Buffers 

■ Output Latch 



5-10 



1502B MTDR Service Manual 



Circuit Descriptions 



The option port interface provides the connection between the processor system and 
external options. This port has a unique protocol that must be followed for proper 
and safe operation. Further information can be obtained by contacting your 
Tektronix customer service representative. A block diagram of the option port 
interface is shown in Figure 5-5. 

The processor system provides all the data and control for the interface. Data, 
Address, and Control lines are all buffered for increased drive. The power to the 
option port is switchable to reduce power consumption, if necessary. The other 
outputs are available for control and protocol purposes. 



Supply Control The +16 VDC and +5 VDC power outputs to the option port are switched supplies 



controlled by the microprocessor system. CS14 and CS15 are used to set and clear 
flip-flop U1011B. This feeds comparators U1012A and U1012B. The positive (+) 
input to the comparators is set at 2.5 volts, so the CMOS flip-flop will drive the 
negative (-) terminals above and below that voltage level. The comparators are 
powered with a +16 VDC and a -12 VDC source to give a good output swing in 
controlling the FET switches. 

The output of U1012A controls the +16 VDC switch and is pulled up via a 20 kQ 
resistor, R201 1 . The output is also passed through two 100 kQ resistors, R2012 and 
R2013, to prevent the FETs from being over-driven. Two parallel FETs, Q201 1 and 
Q2012, control the supply. 

To reduce the instantaneous draw from the instrument supply when first turning the 
switch on, capacitive feedback is used (C2016). This feedback slows the turn-on 
time, allowing a capacitive load to be charged without affecting the instrument 
supply. A stabilizing 100 Q resistor, R2010, is also located in the feedback loop. 





Figure 5-5: Option Port Interface Block Diagram 



1502B MTDR Service Manual 



5-11 



Circuit Descriptions 



Buffers 



Output Latch 



Option Port Wiring 
Configuration 



NOTE. There are specified limits to this type of circuitry. Load specifications must 
be followed. 



The arrangement of the +5 VDC switch is similar except that a 10 kQ TO 1 00 kQ 
resistive divider is used to ensure the switch has a definite turn-on. A single FET, 
Q1010, controls the +5 VDC output. 



Data lines to the option port pass through the bus transceiver, U201 1 . Address lines 
RD’ and WR’ are driven by U2012. CS22, from the processor system, enables these 
drivers with RD controlling the transceiver direction. U2012 outputs are pulled up 
by the switched +5 VDC supply, via R2015. The data lines are pulled down via 
R2014. 

WR’ is a modified write pulse 200 ns long, created to give a rising edge prior to the 
disabling of the drivers. This pulse is created by flip-flop U2033A. 



The output latch U1011A is controlled by Aq and Ai, with select signal CS10. The 
output of this latch is optionally used in the interface protocol. 

Two more lines are used in the option port interface. IR4 is an interrupt signal that 
is active low when creating processor interrupts. R-T TRIG is also available at the 
interface. This is the trigger pulse generated in the analog timebase. 



Label 


J2010 

(on Main Board) 


Option Port 
(D-Connector) 


D 0 


3 


2 


Di 


1 


1 


D 2 


24 


25 


d 3 


22 


24 


d 4 


20 


23 


d 5 


18 


22 


d 6 


16 


21 


d 7 


14 


20 


Ao’ 


12 


19 


Ai’ 


10 


18 


A 2 ’ 


8 


17 


A 3 ’ 


6 


16 


RD’ 


7 


4 


WR’ 


5 


3 


CS22 


9 


5 



5-12 



1502B MTDR Service Manual 



Circuit Descriptions 



Video Processor 

Introduction 





J2010 


Option Port 


Label 


(on Main Board) 


(D-Connector) 


IA 


11 


6 


IR4 


13 


7 


R-T TRIG 


2 


14 


SW+16 


25 


13 




23 


12 


+16rtn 


21 


11 




19 


10 


SW+5 


17 


9 


+5rtn 


4 


15 




15 


8 



The video processor system consists of the following: 

■ Vertical Position DAC 

■ Summing Amplifier 

■ Video Amplifier 

■ Video DAC 

The video processor receives sampled video from the driver/sampler and outputs a 
digitized video signal to the processor system data bus. A block diagram of the video 
processor is shown in Figure 5-6. 



INTERRUPT 

REQUEST 




Figure 5-6: Video Processor Block Diagram 

Vertical position information is loaded by the processor system into a DAC to 
generate a DC signal. Sampled video is combined with this vertical position DC 
voltage in a summing amplifier in order to allow vertical positioning of the 
displayed waveform. 



1502B MTDR Service Manual 



5-13 



Circuit Descriptions 



The combined video and position signal is amplified by the user-selected gain in the 
video amplifier. Gain of the amplifier is set by the processor system via the data bus 
and video amplifier select signal. 

The amplified video is digitized by the video ADC upon receipt of a control signal 
from the processor system. The processor is notified by the ADC interrupt request 
when the conversion has been completed. The processor then reads the value via the 
data bus. 



Vertical Position DAC The vertical position DC voltage is generated by a digital-to-analog converter 

consisting if U2046 and U3041 . DAC integrated circuit U2046 receives a +2.5 VDC 
reference voltage from U3040 and multiplies it by a 14-bit digital value loaded from 
the data bus under control of the processor. The resulting current output of U2046 
is amplified by operational amplifier U3041 to a proportional voltage of zero to 
-2.5 VDC. 

Slimming Amplifier The summing amplifier consists of operational amplifier U8041; input resistors 

R8044, R8046, and R8047 ; and a feedback resistor, R8045. Summation of the DAC 
output through R8047 with the +2.5 VDC reference through R8046 causes the 
vertical position signal range to be enlarged and shifted to achieve an effective 
output of -2.5 VDC to +2.5 VDC. 

Sampled video, through R8044, is summed with the vertical position signal at the 
input node of U8041 . Resistor T8045 determines the gain of U8041 and is paralleled 
with C8040 to reduce high frequency gain for noise reduction. The sampled video 
input may be observed at TP9041. 

Video Amplifier Combined video from the summing amplifier is further amplified by a three-stage 
programmable video amplifier. 

The first stage of this amplifier consists of amplifier U7040, voltage divider T8040 
through R8043, and analog multiplexer U8040. Voltage gains of 0, 16, 32, or 48 dB 
are achieved by switching U8040 to connect one of the four points from the resistive 
voltage divider to the inverting input of U7040. This causes the amplifier gain to 
be equal to the attenuation factor of the voltage divider point selected. 

The second stage consists of amplifier U5040, voltage divider R6040 through 
R6047, and analog multiplexer U6040. This stage operates similar to the first stage 
except eight voltage gains are provided from 0 to 14 dB in 2-dB steps. 

The third stage consists of amplifier U3042, voltage divider T4040 through R4047, 
and analog multiplexer U4040. This stage operates similar to the first and second 
stages except eight voltage gains are provided from 0 to 1.75 dB in 0.25-dB steps. 

Gain of each of the three amplifier stages is controlled by the processor system by 
loading latch U2044 with the appropriate 8-bit word from the data bus. Digital word 



5-14 



1502B MTDR Service Manual 



Circuit Descriptions 



00 (all Os) selects 0 dB gain and word FF (all Is) selects 63.75 dB gain. All 
intervening values of 0.25 dB multiples are similarly chosen. 

The output of the video amplifier is filtered by R2040 and C2043 for noise 
reduction, then sent to the analog-to-digital converter. The output may be observed 
at TP4040 (see Figure 5-7). 













: 




20nS 
































: 




r 










1 1 1 1 






1 1 1 1 


















1 1 1 1 






1 1 1 1 




i 




f 




1 1 






































: 




























500m V 








: 











Figure 5-7: Video Processor Output 



Video Analog-tO-Digital The output of the video amplifier is converted to its digital equivalent value by ADC 
Converter device U2041. The conversion is done using successive approximation technique 
to compare the video voltage to the +2.5 VDC reference from U3040. The device 
is clocked by a 1 .25 MHz clock derived from the timebase oscillator, and completes 
its 12-bit plus sign conversion in approximately 100 [is. 

Gate U2040 provides an OR function for the ADC start conversion trigger and read 
pulses from the processor system. Either pulse selects the ADC for control and 
concurrent pulses select the trigger (WR input) or read (RD input) functions. 

Upon completing a conversion, the processor system is notified by an interrupt 
request (IR0) from U2041. 

Timebase 

Introduction The timebase circuits receive video sample time delay values in digital form from 
the processor system and generate precisely timed strobes to the driver/sampler 
circuits. Digital counters determine the delay in 50 ns multiples, and analog circuits 
further define the delay to fractions of that period. A block diagram of the timebase 
circuits is shown in Figure 5-8 (next page). 



1502B MTDR Service Manual 



5-15 




Circuit Descriptions 



The digital portion of the timebase contains a clock generator that develops all 
frequencies used in the instrument electronics. 




Figure 5-8: Timebase Block Diagram 

A programmable digital counter, clocked at 2.5 MHz, is used to determine the PRT 
(pulse repetition time) of the driver/sampler test pulse. The 1502B is programmed 
with a PRT of 350 [is. The output of the PRT counter is used to trigger a delay 
counter, also clocked at 2.5 MHz, to provide coarse (400-ns resolution) digital time 
delay. The end of this time delay triggers a fine delay counter, which is clocked at 
20 MHz, providing 50-ns resolution to the sampler time delay. Both the coarse time 
delay and the fine delay counters are programmed by the processor via the data bus. 
The end of the coarse delay is used to generate a timebase interrupt request to the 
processor to inform it that a sample is being taken and a timebase update is required 
for the next sample. 

The output of the fine delay counter is provided to the analog timebase circuits for 
further delay control to become the sampler trigger. The beginning of the coarse 
delay counter period is detected by a pulse former, which generates a driver trigger 
for the analog timebase. 



5-16 



1502B MTDR Service Manual 



Circuit Descriptions 



The analog timebase circuits receive the driver and sampler triggers and provide 
strobes to the driver/sampler. The driver trigger is delayed by an analog time delay 
and amplified by a driver circuit to provide the driver strobe. 

The ramp trigger is used to start a linear voltage ramp generator. A voltage 
comparator detects the time when this ramp reaches the programmed voltage of the 
timebase DAC (digital-to-analog converter) and signals a driver to produce a strobe 
for the video sampler. The timebase DAC is programmed by the processor to 
provide a voltage proportional to the portion of the 50-ns time delay period desired. 

Timebase control by the processor system is shown in Figure 5-9. Each period of 
the pulse rate, the processor calculates a new 33-bit digital time delay value for the 
next sample to be taken. The sixteen most significant bits of this value are loaded 
into the coarse delay counter, causing it to count that number of 2.5 MHz clock 
periods before starting the fine delay counter. 



33-BIT 

DIGITAL TIME 
DELAY VALUE 



MSB LSB 




2.5 MHz 
CLOCK 



20 MHZ STROBE TO 

CLOCK SAMPLER 



Figure 5-9: Timebase Control 



The next three bits from the processor time delay value are loaded into the fine delay 
counter. This counter starts at the end of the coarse delay, and counts the selected 
number of 20 MHz clock periods (o through 7) before triggering the analog delay. 

The analog delay circuit receives the 14 least significant bits of the time delay word. 
A digital-to-analog conversion provides a proportional voltage, which is compared 
to a linear voltage ramp to produce the programmed time delay (o to 50 ns). 

The timing diagram in Figure 5-10 (next page) shows the combined effects of the 
three time delays. The output of the PRT counter, waveform (a), begins the coarse 
delay (b). The falling edge of this signal triggers the driver strobe (c), which causes 
a pulse to be applied to the cable test output. 



1502B MTDR Service Manual 



5-17 



Circuit Descriptions 



PRT 

COUNTER 

COURSE 

DELAY 

COUNTER 



DRIVER 

STOBE 



FINE 

DELAY 

COUNTER 



RAMP 

TRIGGER 

[EXPANDED] 



RAMP 

GENERATOR 

[EXPANDED] 



SAMPLER 

STROBE 




u 



16 BIT ►! 

1 PROGRAMMED DELAY [ 




Figure 5-10: Combined Effects of Time Delay 



At the end of the coarse delay, the rising edge of this signal enables the fine delay 
(d), which produces a single ramp trigger pulse after the programmed delay. This 
pulse is shown expanded in waveform (e). The ramp generator waveform (f), also 
shown expanded, has a linear voltage ramp beginning on the falling edge of the 
trigger. This voltage is compared to the voltage from the timebase DAC, such that 
when the ramp exceeds the DAC voltage, the sampler strobe (g) falls. This falling 
edge is used as the sampler strobe for video sampling. 

At the beginning of each sweep, the zero distance reference is calibrated to the 
front-panel connector and the length of the analog ramp to 50 ns. 

Zero distance reference is calibrated by setting the digital and analog timebase for 
zero delay. Then the processor adjusts the driver delay so as to sample at the 10% 
point of the pulse. The ramp is calibrated by removing 50 ns of delay (one 50-ns 
clock cycle) from the sample trigger and then reinserting it with the analog delay. 
The processor adjusts the reference for the timebase DAC so as to sample at the 
previous level. This matches the analog delay to the 50-ns period of the clock. 



5-18 



1502B MTDR Service Manual 



MTDR Service Manual 5-19 




Circuit Descriptions 



Circuit Descriptions 



Digital Timebase 



Analog Timebase 



All digital clocks from the instrument are derived from a 20 MHz crystal oscillator, 
U2031. Flip-flops U2042A and U2042B divide the clock frequency to 10 MHz and 
5 MHz respectively. The 5 MHz output is provided to the microprocessor and to 
TP2041. 

Gate U2034B decodes one of the four states if U2042 and provides a 5 MHz pulse 
to U2033B. Flip-flop U2033B is clocked by the 20 MHz clock and divides the 5 
MHz signals to 2.5 MHz synchronously with the 20 MHz. The 2.5 MHz clock is 
further divided to 1.25 MHz by U2025A and 625 kHz by U2025B. 

The PRT, coarse delay, and real-time counters are contained in a triple, 16-bit, 
programmable counter device, U2030. The PRT and coarse delay counters are 
clocked at the 2.5 MHz rate. The output of the PRT counter, pin 10 of U2030, is 
applied to the trigger input of the coarse delay counter as a start-count signal. The 
negative-going pulse from the coarse delay counter, pin 13 of U2030, is input to a 
two-stage shift register, U2032C and U2032D. This shift register is also clocked at 
2.5 MHz and serves to delay the signal and reduce its skew relative to the 20 MHz 
clock. The Q (inverted output) of U2032C is a positive-going pulse that is supplied 
to a three-stage shift register, U2036B, U2036D, and U2036A, which is clocked at 
20 MHz from inverter U2034A. The leading edge of the pulse is decoded by NAND 
gate U2045B, which also ANDs the signal with the 20 MHz clock from inverter 
U2045A. The resulting driver trigger pulse is a negative-going pulse of nominally 
25 ns width. The falling edge of this pulse is determined by the edge of the 20 MHz 
input to gate U2045B and is used as the driver trigger. 

The coarse delay pulse from shift register U2032D and U2032C us decoded by NOR 
gate U2034C to detect the pulse rising edge (end of the negative pulse). The 
resulting positive pulse is 400 ns wide (one cycle of the 2.5 MHz clock). This pulse 
is shifted through flip-flop U2036C to synchronize it with the 20 MHz clock and 
applied to the count enable input of U2037, a four-bit programmable counter. 

Counter U2037 will have been preset to a count of 8 through 15 by the processor 
through latch U2043 with CS11. While the count enable pulse is present, it will 
count exactly eight times at the 20 MHz rate, thus passing through count 15 after 
0 through 7 clock pulses. The terminal count (TC) output of U2037 is a decode of 
count 15. Thus this signal creates the fine delay pulse after the programmed delay. 
This positive-going pulse is gated with the 20 MHz clock by NAND gate U2045C 
to provide a 25 ns negative-going pulse for the ramp trigger. Ramp timing is derived 
from the trigger falling edge. 

The end of the coarse delay, detected by gate U2034C, is used to clock U2027A, 
which generates an interrupt request to inform the processor that a sample is being 
taken. An acknowledge pulse, CS16, from the address decoder resets this flip-flop. 



The logic level driver trigger from the digital timebase is first amplified by transistor 
stage Q9021 . The trigger is capacitively coupled through C8022 and R9027 to shift 
it to analog levels. The collector of Q9021 is clamped to -0.5 VDC between pulses 
by CR8020 and rises to +6 VDC peak during the 25 ns pulse. This signal is applied 



5-20 



1502B MTDR Service Manual 



Circuit Descriptions 



to C8021 through R8025 to generate an exponentially rising pulse of about 4 VDC 
peak during the pulse width. 

Dual transistor Q8020 is a differential amplifier that is used as a voltage comparator 
to detect when the pulse on C8021 has reached the DC voltage level set through 
U4021B and R8023 by the zero-distance calibration circuit. This DC voltage level, 
from zero to 4 VDC, allows setting the time when the voltage comparator switches 
(a range of about 20 ns). Dual transistor Q9020 is connected as a current source, 
providing a constant 2-mA bias to the emitters of Q8020. Between pulses, this 
current flows through Q8020B. When the exponential pulse reaches the adjustable 
voltage level, the current is rapidly transferred to Q8020A, causing a negative-going 
pulse at R8020. This pulse is coupled to the output stage, Q9010, through C9020 
and R9020. Transistor Q9010 is biased to 0.5 mA between pulses to obtain fast 
turn-on, and provides a positive-going 5 VDC pulse to U8010B and U8010C. 
Flip-flop U7010A is set or reset by the processor to steer the pulse either to the 
option port or the driver. The negative-going pulse from gate U8010B or U8010C 
is logically OR’d by U8010A, then applied to C9010 and R9010. This pulse is fed 
back to the input of the gates U8010B and U8010C through CR9010 to obtain a 
one-shot action, which stretches the driver strobe pulse width to 5 [is. The driver 
strobe is made available at TP9011. 

The ramp trigger pulse from the digital timebase is AC-coupled by C3040 and 
R3041 to Q4040. Diode CR3031 allows the negative-going pulse to pass directly, 
while R3040 limits the input current sue to the re-charging of C3040 between 
pulses. The output of Q4040 is held at ground by L5030 between pulses and rises 
to 6 VDC during the pulse. Choke L5030 is center tapped to provide an equal 
negative-going pulse at its undriven end. This pulse is fed through C5033 and 
R4032 to the emitter of Q4031 to obtain positive feedback to Q4040. This forms a 
one-shot circuit with the pulse width determined by C5033 and R4032. The 25 ns 
ramp trigger pulse is thus stretched to about 80 ns at L5030. 

Dual transistor Q5032 operates as a current source, providing a constant 5-mA 
current, which is used to charge C5032 to create a linear voltage ramp. Between 
ramp trigger pulses, this current is conducted through CR4032 and L5030 to ground, 
creating a voltage of 0.5 VDC on C5032. The positive one-shot pulse from Q4040 
turns off CR4032 and directs the charging current to C5032. The negative-going 
pulse from L5030 is connected to C5032 through CR5030 to provide a cancelling 
effect for the positive pulse being coupled through the capacitance of CR4032. 

The linear rising voltage pulse from C5032 is buffered by source-follower Q5031 
and emitter-follower Q5030 to provide a low output impedance and prevent loading 
the ramp. Transistor Q7030 provides a constant 2-mA bias current to junction FET 
Q5031. 

The ramp voltage is AC-coupled to voltage comparator Q7021 by C7030 to remove 
the DC offset voltage developed in the preceding circuits. A small negative DC 
voltage of approximately -200 mV is added by voltage divider R7032 and R7025 
to hold the voltage comparator off between pulses. 



1502B MTDR Service Manual 



5-21 



Circuit Descriptions 



Voltage comparator Q7021 is biased at 2 mA by dual transistor Q5020. During the 
linearly rising ramp voltage, it compares the ramp to a programmed DC sample 
reference voltage produced by the timebase DAC circuit. When the ramp reaches 
the sample reference value, Q7021A rapidly turns on to produce a negative-going 
signal across R7024. This pulse is coupled through C7022 and R7021 to turn on 
Q6020, providing a positive pulse to the base of Q7020. The negative-going sampler 
strobe coming from Q7020 is supplied to the sampler and to TP7010. 

Timebase DAC U4020 and amplifier U5010 inverts and multiplies Vref by the 
14-bit digital word loaded by the processor. It is filtered for noise by R7026 and 
C5023 and connected to comparator Q7021 through R7027 to set the analog delay 
(0 to 50 ns). 

To calibrate the analog delay to 50 ns, the processor sets IR2 (IR2 high) and loads 
a new 12-bit word in latches U3021 and U3022 (max 1-bit change per sweep) with 
chip selects CS11 and CS12. DAC U3023 multiplies the reference current (1 mA 
set by R3020) by the digital word from the latches. The DAC output current and 
the current from the last two LSBs (which comes from the latches through R3031, 
R3033, R3039, and R4020) are summed by U4021A and forced through R4021. 
This develops a correction voltage at TP4020 of ± 5 VDC and a sensitivity of 
2.5 mV per bit (the currents from the LSBs have been complimented by the 
processor to correct their phase). The DAC circuit is designed to nominally run at 
half of full dynamic range (2048/4096) of 2 mA, that generate 1 mA of current at 
the summing node. That current is balanced out by 1 mA of current from R4020, 
giving a nominal output of zero volts at TP4020 and TP4021. 

U5020, R5020, R5021, and C5021 scale the correction signal (up to ± 5 VDC) at 
TP4020 to ± 0.4 VDC at Vref of U4020. Resistors R5023 and R5022 furnish a 
current to offset Vref to a -4 VDC ± 0.4 VDC (equivalent to ± 5 ns) correction 
signal to the 50 ns analog delay. 

To calibrate, the zero-distance delay (IR2) is set low, and through R3037 and 
CR3030, turns on Q3030, whose collector (through R3036 and R3035) raises the 
cathode of CR4030 to +6 VDC. This allows R4023 to turn on Q4030. Capacitor 
C4022, through R4030 and Q4030, is charged to the new corrected level at TP4020 
that was asked for by the processor. The correction voltage on C4022 from buffer 
amplifier U4021B is scaled by voltage divider R8023, R8022, and R8021 from a 
range of ± 5 VDC to a range of zero to 3.5 VDC. This voltage is applied to the base 
of comparator Q8020B, which provides ± 10 ns of zero-distance delay adjustment. 
Components C3048, R3042, R2032, C3047, R2034, and C8024 are used to reduce 
jitter and cross-coupling between circuits. 



Elapsed Time Indicator 

(SN <B020511 only) 

An elapsed time indicator, Ml 030, is provided to measure the cumulative time the 
instrument has been turned on. A small bead travels in the indicator as current flows 
through it, indicating the time during which the instrument has been operating (from 



5-22 



1502B MTDR Service Manual 



Circuit Descriptions 



Driver/Sampler 

Introduction 



Second Sampler 



zero to 5,000 hours). After the bead has reached 5,000 hours, the indicator may be 
replaced, or simply removed and installed backwards, in which case the bead will 
travel from 5,000 to zero hours and would have to be read backwards (see 
Maintenance chapter). 



The front-end consists of: 

■ Hybrid Sampler/Step Generator 

■ Second Sampler 

■ First Sampler Bridge Bias Generator 

■ Trigger Pulse Shapers 

■ Power Supply Conditioning 

The function of this board is to generate the step test signal and to sample and hold 
the reflections from the cable under test. A block diagram of these circuits is shown 
in Figure 5-12 (next page). 

Most of the primary active circuitry is located within the hybrid. The balance of the 
Driver/Sampler Board is dedicated to interfacing with the rest of the instrument. 

The step generator is triggered by a negative pulse from the Main Board. One of the 
trigger pulse shapers stretches this to 25 [is to set the length of the output step. The 
0.6 V adjustable power source sets the “on” voltage for the output step. 

The sampler is also triggered by a negative pulse from the Main Board. Inside the 
hybrid, this trigger causes the strobe generator to apply 50-ps pulses to turn on the 
bridge, capturing a portion of the input waveform. This sample is stored outside the 
hybrid in the second sampler to reduce droop rate. The stored signal goes two places: 
back to the Main Board as the video output, and to the bridge bias circuit, which 
holds the sampling bridge off between samples. 



The video signal from the hybrid is sent to the second sampler. The second sampler 
reduces the droop rate to about 1 LSB/ms. This is accomplished by buffering the 
signal through U2050B and storing it in C2053 via the FET switch, Q1060. The FET 
is strobed by the one-shot U3030B for 5 [is after the sample is taken. The voltage 
stored on C2053 is buffered by op-amp U2050A, then inverted and amplified by 
U1050A. The strobe signal for the FET can be observed at TP2060, and the inverted 
video output at TP1060. The signal from the second sampler buffer, U2050A, is also 
fed to the bridge bias amp, U1070, via R1060. 



1502B MTDR Service Manual 



5-23 



Circuit Descriptions 




Figure 5-12: Driver/Sampler Block Diagram 

Bridge Bias The bridge bias for the first sampler is set by U1070. With a zero voltage input 
signal, the circuit holds ± 2.0 V on the bridge inputs. As the input signal moves, the 
4 V window also moves to stay centered around it. This centering is accomplished 
by feeding part of the output of U2050A into the bridge bias circuit. The outputs of 
the bridge bias circuit are available on TP 1020 and TP 1021. 



Trigger Pulse Shapers 



There a\re two incoming triggers: the sample and the step. Both require modification 
before they are usable by the hybrid. The sample trigger is a 30-to-50-ns negative 
TTL signal. This pulse is buffered by Q2030, then coupled to the hybrid through 
T1020. This provides a differential drive that can have common-mode voltage on 
it. The sampler pulse is also stretched to 5 [is by U3030B to strobe the second 
sampler. The step trigger, GEN TRIG, is a 3-to-5-[is negative TTL signal, stretched 
to the proper 25 [is pulse length by U3030A. CR3020 and CR3021 provide a logic 
OR of the incoming signal and the output of the one-shot. This prevents the 
introduction of jitter on the trigger signal. The OR output can be observed at 
TP3020. 



Power Supply Conditioner 



There are seven power supplies for the hybrid: ± 5 Vs, ±5 Vp, ± 12 V, and +0.6 V. 
The ±5 V supplies come on board as 5 V, so they require no regulation, but are 
merely filtered before being used by the hybrid and the board. The ± 12 V supplies 
enter the board as ± 15 V, so the necessary filtering and regulation is accomplished 
by U3070 and associated circuitry. The +0.6 V supply is used by the hybrid to set 



5-24 



1502B MTDR Service Manual 



Circuit Descriptions 



Front Panel 

Introduction 



Push Button Switches and 
Latches 



the output step height. It is referenced to the +5 V supply and controlled by U 1050B 
and Q1030. 

The +0.6 V supply is adjustable via R1042 to allow the offset of the step generator 
to be zeroed out. CR1040 temperature compensates the +0.6 V supply against 
variations in the hybrid. The test points for these supplies are as follows: 



The Front Panel Board consists of the following circuits for these controls: 

■ Push Button Switches and Latches 

■ Rotary Binary Switches 

■ Resistive Shaft Encoders 

■ Analog-to-Digital Converter for Shaft Encoders 

The Front Panel Board consists of the following circuits for the display module: 

■ Electroluminescent Backlight Switch and Power Supply 

■ Display Heater Circuitry 

■ Display Drive Voltage (Contrast) Temperature Compensation 

The Front Panel Board contains most of the instrument control as well as some 
circuitry for the display module. A block diagram of the Front Panel Board is shown 
in Figure 5-13 (next page). 



The push button switches are normally open momentary switches When depressed, 
these switches tie the inputs of NOR gate latches U3021, U3022, and U3023 to +5 
VDC, setting the latches. The latches are reset by control signal ADCRD. The 
processor updates the instrument configuration by periodically reading the state of 
the latches through multiplexers U2024, U3025, and U3031. 



+5 V 
-5 V 
+12 V 
-12 V 
+0.6 V 
Ground 



TP1083 

TP1084 

TP1080 

TP1081 

TP1030 

TP1082 



1502B MTDR Service Manual 



5-25 



Circuit Descriptions 



Push Button Switches 




Figure 5-13: Front Panel Block Diagram 



Connector 



5-26 



1502B MTDR Service Manual 



Circuit Descriptions 



Rotary Binary Switches 



Switch Multiplexers 



Resistive Shaft Encoders 



Analog-to-Digital 

Converter 



These switches control: 

■ MENU 

■ VIEW INPUT 

■ VIEW STORE 

■ VIEW DIFF 

■ STORE 



The rotary binary switches provide a 4-bit binary value, indicating their position. 
The outputs are tied to the inputs of the multiplexers. The position of the rotary 
switches control the following functions: 

■ FILTERING, SET REF, SET DELTA 

■ HORIZONTAL GAIN (DIST/DIV) 

■ V P COARSE 

■ V P FINE 



The switch multiplexers are U2024, U2025, U3025, and U3031. These dual 
four-channel multiplexers multiplex the switch settings of the push button and 
rotary switches onto the data bus. The control signal MUXCS, in conjunction with 
A 2 , selects the multiplexers while Aq and Ai determine which switch bank is placed 
on the data bus. 



The resistive shaft encoders R1022, R2024, and R3020 are dual-concentric, 360° 
rotation potentiometers, with the wipers set 180° out of phase with respect to each 
other. The wipers are tied to the analog-to-digital converter inputs of ADC U2023. 
The three resistive shaft encoders control the following functions: 

■ VERTICAL GAIN 

■ VERTICAL POSITION 

■ HORIZONTAL POSITION (Cursor) 



The ADC, U2023, is an eight-channel analog-to-digital converter. It converts the 
voltages on the wipers of the resistive shaft encoders to a digital value, depending 
on the position of the encoders. It also converts the voltage on the display thermistor 
(Tsense) and the chart recorder thermistor divider circuits into digital values 
representing the corresponding temperatures. The temperature data is used by the 
processor to compensate the LCD drive voltage and chart recorder print parameters 
for variations in temperature. 

The control signal TRIG ADC is used to start a conversion; ADC RD reads the 
value; and Aq, Ai, and A 2 select one of the eight channels for conversion. Control 
signal EOC notifies the processor of a conversion completion, via the IR3 line. 



1502B MTDR Service Manual 



5-27 



Circuit Descriptions 



Electroluminescent 
Backlight Switch and 
Power Supply 



Display Heater Circuitry 



Display Temperature 
Compensation 



The EL (electroluminescent) backlight is switched by software. Control signal 
LIGHTCS, with RD or WR, sets or resets (respectively) NOR latch U3020. The 
output of the latch is applied to the + side of comparator U2020B; the - side is held 
at 2.5 VDC. When the output of the latch is high, the comparator output is +16 VDC, 
which turns off the gate of P-channel FET Q1030, turning off power to the EL power 
supply, PS2030. When the output is low, the comparator output is OV, which turns 
on the FET, turning on the power to the EL power supply. R103 1 , C3030, and C303 1 
serve to filter noise introduced to the +16 VDC supply by the EL power supply. 



The display heater circuitry regulates the application of power to the display heater 
(see Indium Tin Oxide Heater later in this chapter for more information). When the 
display thermistor divider senses the display temperature has dropped below 
+10° C, the heater can be turned on if the control signal HEAT ENABLE is not 
asserted. For reasons of power economy, the chart recorder and display heater are 
not allowed to operate concurrently. The processor does this by asserting HEAT 
ENABLE while making a chart recording. When HEAT ENABLE is low, 
N-channel FET Q2020 is off, making the voltage on the + side of the comparator, 
U2020A, approximately +5 VDC. This will allow the + side (chart recorder) to 
always be greater than the - side (display thermistor divider voltage). The output 
of the comparator will be +16 VDC, which turns off P-channel FET Q1020. This 
turns off the power to the display heater.. 

When HEAT DISABLE is high, Q2020 will turn on and the voltage on the + side 
of the comparator will be approximately 2.5 volts. When the display thermistor 
divider voltage (- side) is above 2.5 volts (about +10° C), the comparator output will 
be 0 V, which will turn on Q1020. This will turn on the heater. As the temperature 
rises above +10° C, the thermistor divider voltage will be less than 2.5 V and Q1020 
will turn off, shutting off power to the heater. 



The LCD drive voltage compensation circuitry adjusts the drive voltage (contrast) 
to assure a constant display contrast within the operating temperature range of the 
instrument. The display thermistor is attached to the LCD and forms the sensor in 
the display thermistor divider circuit. Its output is a voltage related to the display 
temperature. This voltage is read by the processor through the analog-to-digital 
converter, U2023. The processor uses this voltage value to determine a drive 
voltage. This is sent to digital-to-analog converter U2021 via the data bus. The 
output of the DAC is amplified to op-amp U2010A and applied as the LCD drive 
voltage. As the temperature of the display (thermistor divider voltage) changes, the 
processor modifies the drive voltage via the DAC. In this manner, the drive voltage 
is compensated due to variations in display temperature. Trimmer potentiometer 
R1011 is used to offset the drive voltage produced by U2010A to compensate for 
variations in display cells and thermistors. 



5-28 



1502B MTDR Service Manual 



Circuit Descriptions 



Display Module 

Introduction 



The display module consists of the following: 

■ LCD Cell 

■ Row Driver/Controller Board and Column Driver Board 

■ Electroluminescent Backlight 

■ Indium Tin Oxide (ITO) Heater 

■ Mechanical frame, which supports the above subassemblies 

The display module function is to take bit pattern data generated by the instrument 
internal electronics and display it on the LCD. A block diagram of the display 
module is shown in Figure 5-14. 




Figure 5-14: Display Module Block Diagram 

The LCD cell is the “video screen” that displays information generated by the 
processor. The processor updates the display memory periodically with a new 
picture and the display memory holds this bit pattern data. This data is received by 
the display controller and sent to the drivers along with some control and timing 
signals that provide operating information to the drivers. The row and column 
drivers are attached electrically to the LCD cell through elastomeric connectors and 



1502B MTDR Service Manual 



5-29 



Circuit Descriptions 



a flex cable. These drivers place signal voltages on the electrode matrix in the LCD 
cell and thus generate the video display. 

There are other circuits contained in the display module. An indium tin oxide (ITO) 
heater warms the display during cold temperatures. A temperature sensor attached 
to the display provides display temperature data to the heater and drive voltage 
circuitry (see Front Panel text in this chapter). An electroluminescent backlight 
provides illumination in low light conditions. 



LCD Cell The LCD cell provided in the 1502B uses an advanced technology known as 
Superbirefringent Effect (SBE) to obtain greatly improved contrast and viewing 
angle over conventional LCD cells. The function of the LCD module is to receive 
bit pattern data from the CPU and display it. 

First, the processor generates a 4k X 8-bit pattern image in its own memory. It then 
writes this bit pattern, via the data bus, to the display memory, U1040, in the form 
of a block transfer. The bit pattern is mapped in the display memory and later on the 
LCD cell. 

Second, the LCD controller, U2040, reads the bit pattern from the display RAM, 
formats it, and sends it to the column drivers. 

Last, the column drivers and the row drivers generate select and non-select voltages 
based on the timing, control, and data signals received from the controller. These 
voltages are applied to the LCD cell matrix, turning off and on pixels that match the 
bit pattern in the display memory. The pattern of pixels form the image on the 
display. 

The cell is physically composed of two planes of glass, two polarizers, a matrix of 
transparent electrodes, and a filling of liquid crystal material. A plating of indium 
tin oxide on the back plane of glass is used as a heater, but is not used in the display 
process. 

Electrically, the cell is a 128 X 256 pixel display, each pixel being an intersection 
of a row and a column. These intersections are like small capacitors. When a 
non-select voltage (about 1.5 VRMS) is applied to a row and a column, their 
intersection is turned off (see Figure 5-15, next page). That is, light is allowed to 
pass through the display and reflect back from the transflector, creating an “off’ 
pixel. A select voltage (about 1.7 VRMS) turns the intersection on. That is, the light 
is not allowed to pass through the crystalline material and is, therefore, not reflected 
back from the transflector, creating an “on” pixel. 



5-30 



1502B MTDR Service Manual 



Circuit Descriptions 



Row and Column Drivers 



3 


J3 








o 


o 


13 


J3 




§ 


§ 


O 

§ 


O 

§ 


J3 

o 

§ 


ro 


ro 


cd 


CD 


00 




cn 


-1^ 


ro 




SCREEN SCREEN 



COLUMN 1 
COLUMN 2 



COLUMN 255 
COLUMN 256 



Figure 5—15: SBE Cell 



There is one row driver, located on the Row Driver/Controller Board. There are eight 
column drivers, located on the Column Driver Board. The row and column drivers 
receive control, timing, and data signals from the controller and translate them to 
properly timed voltages that are placed on the pixel matrix. The voltages are placed 
on the matrix by the flex cable for the rows and by the elastomers for the columns. 



LP 




ST 



Vccd 

V5 

V2 

+5 



ROW 64 - ROW 1 28 ROW 1 - ROW 65 

Figure 5-16: Row Driver Block Diagram 



1502B MTDR Service Manual 



5-31 



Circuit Descriptions 



Row Driver 



The function of the row driver is to sequentially address each of the rows of the 
display. The on or off state of the pixels on the addressed row is then determined by 
the voltages on the columns. The row driver addresses each line, one after another, 
completing the scanning at the refresh rate of 125 Hz. 

The column driver is similar to the row driver except bit pattern data is level- shifted 
rather than the start pulse. The column drivers provide select and non- select voltages 
to the column electrodes according to the bit pattern data. The presence of select 
or non-select voltages on the columns, in conjunction with the currently selected 
row pair determine which pixels are on or off on that row pair. The column drivers 
regulate the select and non-select voltages as the row drivers select rows. The result 
is a bit pattern displayed on the screen that represents a waveform. 




Eout 

Xscl 



D3 

D2 

D1 

DO 



LP 



Fr 



Column X Column X 64 



Figure 5-17: Column Driver Block Diagram 



The row driver is an 80-pin flat pack located on the Row Driver/Controller Board. 
It is composed of a 64-bit shift register, U2020, a 64-bit latch, and a 64-bit level 
shifter. The row driver has the following relevant inputs: 

■ ST <start pulse>: Input to the shift register <Din on SED 1190> 

■ LP <latch pulse = LATCH>: Falling-edge triggered, this shifts data in the shift 
register and latches contents of the shift register into the latch <Y Scl on 
SED 1190> 



5-32 



1502B MTDR Service Manual 



Circuit Descriptions 



Column Driver 



■ FR <frame signal>: Defines the select and non-select voltages. 

The relevant outputs: 

Row 1 through 64 are paralleled outputs driving both sides of the display. One set 
of outputs drive rows 1 through 64 and the other set drive rows 65 through 128 on 
the LCD. 

Supply Voltages include the following: 

■ +5 VDC supply voltage for logic and select drive voltage 

■ V 2 non- select drive voltage 

■ V 5 non- select drive voltage 

■ Vlcd select voltage 

■ GND return for +5 VDC. 

To perform its function, the row driver receives a start pulse at the beginning of a 
frame. LP shifts this start pulse into the shift register. The contents are then 
transferred to the latch. The level shifter shifts the logical Is and Os in the latch into 
select and non-select voltages according to FR (see table at top of next page). 



FR 


Bit X in Latch 


Row X Output 


0 


0 


V 5 non-select 


0 


1 


+5 VDC select 


1 


0 


V 2 non-select 


1 


1 


V LC D select 



ST, LP, and FR are sent by the controller in such a way that a scanning select voltage 
is applied sequentially to the rows, with the polarity of the select voltage alternating 
with FR, every frame. The alteration is required to place an AC voltage on the pixels. 



A column driver is composed of several blocks: 16-position, 4-bit wide shift 
register; 64-bit latch; 64-bit level shifter; and an enable flip-flop. 

A column driver has the following relevant inputs: 

■ D3-D0 <data MSB to data LSB>: Bit pattern data for data formatted and sent 
by the controller 

■ XSCL ccolumn (X) shift clock>: Shifts D3-D0 in parallel groups of four bits 

■ LP <latch pulse>: Latches data in shift register into 64-bit latch 

■ FR <frame signal>: Defines select and non- select voltages 

■ Ei N <enable in>: Input to the enable flip-flop 

■ E C lk <enable clock>: Clocks Ejn into the enable flip-flop. 



1502B MTDR Service Manual 



5-33 



Circuit Descriptions 



1 Frame = 8 ms 





j 







- +5 

- V2 



-Scanning select pulse 



V5 — 
V LDC — 





V5 — 
V LDC — 



- +5 

- V2 





$ 







Figure 5-18: Row Timing Diagram 



5-34 



1502B MTDR Service Manual 



Circuit Descriptions 



One Line 







First Column Second Column Third Column Forth Column 
Driver Pair Driver Pair Driver Pair Driver Pair 
Enable Enable Enable Enable 




_ri^^^rumjui^^^riJULm^riJULrm^n^_rLrm 

|< 64-LP t| 

j i r 





One Frame 



Figure 5-19: Column Timing Diagram 



1502B MTDR Service Manual 



5-35 



Circuit Descriptions 



The relevant outputs: 

■ Columns 1 to 64: These are the 64 outputs from the level shifter. 



NOTE. The manufacturer’s pinout of the outputs are numbered in order of shift (seg 
63 - seg 0). The nomenclature herein refers to the outputs in column order. 
Therefore, seg 63 corresponds to Column 1 and seg 0 corresponds to Column 64. 



■ EOUT: Output from the enable flip-flop. 



Supply Voltages include the following: 

■ +5 VDC supply voltage for logic and select drive voltage 

■ V 3 non- select voltage 

■ V 4 non- select voltage 

■ Vlcd select voltage 

■ GND return for +5 VDC 



To perform its function, the column driver shift registers are filled with data by 
receiving data, XSCL, Eclk? and Ejn from the controller. LP then latches the 
contents of the shift registers into the latches. The level shifter translates the logical 
Is and Os in the latch into select and non-select voltages according to FR (see table). 



FR 


Bit X in Latch 


Column X Output 


0 


0 


v 4 


0 


1 


V LCD 


1 


0 


h 


1 


1 


+5 VDC 



The pixels selected by both the column drivers and the row driver are turned on; all 
others are off. The process of filling the column drivers is repeated every LP (i.e., 
for every addressed row until all lines in both screen halves have been refreshed). 
One frame is thus complete and the entire process is repeated. 



5-36 



1502B MTDR Service Manual 



Circuit Descriptions 



Display Memory 



Controller 



Row Driver Interface 




Shift Register Detail 



Figure 5-20: Shift Register 



The display memory is an 8k X 8 RAM (only 4k X 8 is used), located on the Row 
Driver/Controller Board. The display memory stores the current bit pattern 
generated by the processor on the Main Board. The processor interrupts the 
controller periodically and places a new bit pattern in the display memory. The 
controller then reads the bit pattern out of the display memory, formats it, and sends 
it to the column drivers. 



The controller, located on the Row Driver/Controller Board, generates control and 
timing signals for the row and column drivers, and formats bit pattern data stored 
in the display memory, which is then sent to the column drivers. 

The function of the controller is to read bit pattern data from the display memory 
and format it. This data is then sent (along with control and timing signals) to the 
column and row drivers, which drive the LCD to provide the pattern on the display. 



The row driver requires a start pulse at the beginning of each frame, 64 latch pulses 
following that to scan the start pulse down the rows, and a framing signal to generate 
the AC select voltage. These signals are generated by the controller as shown in the 
row driver timing diagram (Figure 5-18). 

The controller, running at a clock rate of 0.625 MHz, generates ST, LP, and FR with 
the following periods: 



ST 


8 ms 


LP 


125 ns 


FR 


16 ms 



1502B MTDR Service Manual 



5-37 



Circuit Descriptions 



NOTE. The manufacturer’s nomenclature on the controller differs somewhat: ST = 
FRP, LP = LIP, and FR = FRMB. 



Column Driver Interface Thee column drivers require more control and timing signals than the row driver. 

These include: Ejn, Eclk? XSCL, D3 - DO, LP, and FR. 

Ei N is required at the start of every line to enable the first (leftmost, as seen from the 
front of the display) column driver pair. 

E C lk is required once to latch in Ejn and three times after that to enable the 
successive column driver pairs. Each successive Eclk must occur every 16 XSCL 
pulses (i.e., after each column driver pair is full of 64 bits (4 X 16 bits)). 

XSCL is required 16 times per column driver pair per line to shift in the bit pattern 
data. Therefore, a total of 64 XSCL are required per line for the four column driver 
pairs. 

XSCL is generated by U3030, a counter clocked by CLP or LP from the controller. 
It must be generated as such because the controller was designed to use with 
80-channel column drivers instead of 64-channel column drivers. The controller 
version of Eclk? CEO, is generated every 20 XSCL pulses rather than every 16 
XSCL pulses as required by the 64-channel column drivers. The counter is used to 
translate XSCL into Eclk- 

As a consequence of generating Eclk as above, Ejn must also be generated. This 
is done with the U3065 flip-flop pair. The flip-flop pair is set when LP and LEO are 
asserted and hold set until XSCL (CLP) shifts in a logic 0 after the pulse. Ejn is held 
high for a duration long enough to enable the first column driver pair. 



CPU and Display Memory There are two data buses and two address buses on the controller. The first data bus, 

Interface DB7 - DBO, is used to access registers internal to the controller. These internal 

registers are used to initialize the controller. 

The second data bus, RD7 - RDO, is used to read bit pattern data from the display 
memory. The data bus from the display memory is tied directly to the RD7 - RDO 
data bus, and indirectly through a bidirectional bus transceiver, U1050, to the DB7 
- DBO data bus. The DB7 - DBO data bus is tied directly to the CPU data bus through 
the 40-pin connector. 

The first address bus, MA12 - MAO, is tied to the display memory and addresses 
it. MA12 - MAO can have one of two sources. The first is an internal address in the 
controller, which is the address of the currently accessed bit pattern data byte. The 
second is the address resent on the second address bus, All - AO. 



5-38 



1502B MTDR Service Manual 



Circuit Descriptions 



CS 



RD 



WR 



X X 



D7-D0 




Read Data from Write Data to 

Internal Register Internal Register 

Read and Write for Internal Register Timing 



PRAM 



RD 



WR 



WR on RAM 



OE on RAM 



X 




X 




X 




X 



Read Data from 
Display Memory 
to CPU 



Read Data from 
Display Memory 
to Controller 



Write Data to 
Display Memory 
from CPU 



Figure 5-21 : CPU and Display Memory Interface 



1502B MTDR Service Manual 



5-39 



Circuit Descriptions 



This second address bus is tied to the CPU address bus through the 40-pin connector 
and is used to address the display memory during the time the CPU is updating the 
display memory. 

The control signal DIEN controls the multiplexing of the internal address and All 
- AO to MA12 - MAO. A15 - A12 are tied low. 

There are several other relevant control signals to the controller: CS <chip select>, 
WR <write>, and RD <read>. 

CS and WR are used in conjunction with AO to write to the internal registers. CS 
and RD in conjunction with AO to read them. 

XT is the system clock, from which all timing in the controller is derived. It is 
supplied via the 40-pin connector at 0.625 MHz. 

DRAM <display memory select> is used with WR by the CPU to select and write 
to the display memory. DRAM and RD are used to read. 

The combinational logic associated with the selection of the display memory is such 
that the memory is set to the selected read mode at all times except when the CPU 
accesses it. In that case, it could be either selected read or selected write at the 
discretion of the CPU. This combinational logic also controls the flow of data 
through the transceiver. 

In operation, the controller is usually accessing the display memory and refreshing 
the screen with the bit pattern data. At the rate of about 10 Hz, the CPU intervenes 
in the refresh operation to update the bit pattern display memory. This operation 
occurs as a block transfer of 4k X 8 from the CPU memory to the display memory. 
This block transfer takes place in about 17 ms. During thew block transfer, the 
controller cannot access display memory and, therefore, sends null data to the 
display. 



Electroluminescent Because the LCD display is non-emitting, a light source is needed for low light 

Backlight applications. This source is provided by an electroluminescent (EL) backlight 

behind the transflector. The EL backlight is a long-life device, requiring a 130 VAC, 
400 Hz supply. This supply is routed from the Front Panel Board through the 40-pin 
connector to pads on the Row Driver/Controller Board. The leads on the backlight 
are then attached to these pads. 




CAUTION. The pads for the EL backlight are exposed when the display module is 
removed from the front panel. They operate from a high voltage source. Do not turn 
on the backlight when the pads are exposed. 



5-40 



1502B MTDR Service Manual 



Circuit Descriptions 



Indium Tin Oxide Heater Because the LCD display response time slows down rapidly at temperatures below 

+10° C, a heater is required to maintain the temperature of the LCD cell at +10° C 
when the ambient temperature falls below +10° C. 

The heating element is a resistive plating of indium tin oxide (ITO) on the back side 
of the row pane. This plating has a resistance of about 64Q The power for the heater 
is supplied through the 40-pin connector to pads on the Row Driver/Controller 
Board, similar to those for the EL backlight. 

A thermistor, RT1030, is attached to the lip of the row pane opposite the cable. This 
thermistor is used to track the temperature of the LCD cell and turn on the heater 
power (+16 VDC) when the temperature falls below +5° C. With a supply voltage 
of +16 VDC, the heater dissipates about 4W. The circuitry to control the temperature 
is located on the Front Panel Board. The thermistor leads are attached to pads on the 
Row Driver/Controller Board, similar to the heater, and routed through the 40-pin 
connector. 



1502B MTDR Service Manual 



5-41 



Circuit Descriptions 



5-42 



1502B MTDR Service Manual 



Calibration 



Introduction 



This chapter is divided into the Calibration Performance Check and the Adjustment 
Procedure. 

The Calibration Performance Check is a series of checks to compare the instrument 
parameters to the published specifications. This procedure is similar to the Operator 
Performance Check (Chapter 2), but additionally lists actions to take if the 
Calibration Performance Check is not met. 

The Adjustment Procedure is a series of steps designed to bring the instrument up 
to standards after repair or performance check. 

Calibration Performance Check 



The purpose of this procedure is to assure that the instrument is in good working 
condition and should be performed on an instrument that has been serviced or 
repaired, as well as at regular intervals. 

This procedure is not intended to familiarize you with the instrument. If you are not 
experienced with this instrument, you should read the Operation chapter of this 
manual before going on with these checks. 

If the instrument fails any of these tests, it should be calibrated or otherwise 
serviced. Many failure modes affect only some functions of the instrument. 



Equipment Required 



Equipment 


Tek Part Number 


50Q precision terminator 


011-0123-00 


3-ft precision coaxial cable 


012-1350-00 



Getting Ready Disconnect any cables from the front panel CABLE connector. Connect the 
instrument to a suitable power source (a fully charged optional battery pack or AC 
line source). If you are using AC power, make sure the fuse and power selector 
switch on the rear panel are correct for the voltage you are using (115 VAC requires 
a different fuse than 230 VAC). 

Metric Instruments Option 05 (metric) instruments default to m/div instead of ft/div. You can change 
this in the Setup menu, or you may use the metric numbers provided. To change the 
readings to ft/div, press the MENU button. Scroll down to Distance/Div is: m/div 



1502B MTDR Service Manual 



6-1 




Calibration 



and press MENU again. That menu line will change to Distance/Div is: ft/div. Exit 
by pressing MENU until the instrument returns to normal operation. If the 
instrument power is turned off, this procedure must be repeated when the instrument 
is again powered up. 

The metric default can be changed to standard default. See the Maintenance chapter 
of this manual for details. 



Display Module Check 



Liquid Crystal Display 

1. Pull the POWER switch on the front panel. If a message does not appear on the 
display within a few seconds, turn the instrument off. 



If start-up assistance needed, 
Push MENU button. 

1502B ROM version 5.02 
Ethernet 

Copyright 1992 Tektronix 
Redmond, OR 



Figure 6-1 : Typical Start-Up Display 




CAUTION. There are some failure modes that could permanently damage the LCD 
if the power is left on more than a minute or so. 



2. Observe that the LCD characters and waveform are legible. If the LCD is too 
dark or smeared, or if the display has patches of low contrast, refer to the 
Adjustment Procedures section of this chapter. 




6-2 



1502B MTDR Service Manual 



Calibration 



EL Backlight 



NOTE, if the LCD does not appear to be working properly, refer to the 
Troubleshooting section in the Maintenance chapter as well as the Circuit 
Description chapter of this manual. 



The EL backlight should come on with power up. The LCD will have a light-green 
glow. 

1. Press MENU. 

2. Use the ^POSITION control to scroll to Setup Menu. 

3. Press MENU again. 

4. Use the y POSITION control to scroll to Light is: ON. 



Exit Setup Menu 
Acquisition Control Menu 
Vertical Scale is: Decibels 
Distance/D iv is: ft/div 
Light is: ON 



Move 0 Position to select, then push MENU button 



Figure 6-3: Setup Menu 

5. Press MENU. The EL backlight should go off and the menu line will change to 
Light is: OFF. 

6. Scroll to Light is: OFF and press MENU to turn the light back on. 

7. Press MENU again to exit the Setup Menu. 

8. Press MENU again to exit the Main Menu. 

You should be able to read the LCD in all conditions of illumination, from full 
sunlight to a darkened room. The EL backlight might very gradually begin to 
decrease in brightness after approximately 3,000 hours of use. 



NOTE. If the EL Backlight is dim or does not work properly, refer to the 
Troubleshooting section or the EL Backlight Replacement section in the 
Maintenance chapter of this manual. 



1502B MTDR Service Manual 



6-3 



Calibration 



Front Panel Check 



If the instrument fails any of these checks, measurements corresponding to the failed 
control might be inaccurate or unobtainable. 



Presets and Menu Access 

1. Set the front-panel controls: 

No connection 
Full CW 

Default (see note below) 
Full CW 
.30 
Off 



CABLE 
NOISE FILTER 
VERT SCALE 
DIST/DIV 
V P 

POWER 



NOTE. A default setting is where the instrument will be set when power is switched 
on. For example, VERT SCALE will always be 0.00 dB when the instrument is 
powered on. 



2. Turn POWER on. Wait for initialization and normal operation display. 

3. Press MENU. 

4. Use the y POSITION control to scroll to Diagnostics Menu. 



Return to Normal Operation 
Help with Instrument Controls 
Cable Information Menu 
Setup Menu 
Diagnostics Menu 
View Stored Waveform Settings 
Option Port Menu 

Move 0 Position to select, then push MENU button 



Figure 6-4: Main Menu 

5. Press MENU. This will display the Diagnostics Menu. 



6-4 



1502B MTDR Service Manual 



Calibration 



Pushbutton Switches 



Rotating Controls 



Exit Diagnostics Menu 
Service Diagnostic Menu 
Front Panel Diagnostic 
LCD Diagnostics Menu 
Chart Diagnostics Menu 

Move ^ Position to select, then push MENU button 



Figure 6-5: Diagnostics Menu 

6. Use the ^POSITION control to scroll to Front Panel Diagnostic. 

7. Press MENU. This will display the Front Panel Diagnostics. 

1. Press VIEW INPUT. The LCD switch reading should change to 1 (see Figure 
6-6, third line of text). 



Front Panel Diagnostic, test all switches. 
Hold down MENU button to Exit. 

Switch: 1^ tciv,|S. C5 — 

Vp: 0.30 



<> Control 




76 


253 


v Control 




97 


255 


Vertical Scale 




230 


61 



Switch Reading 



Figure 6-6: Front Panel Diagnostic Display 



2. Press VIEW STORE. The LCD switch reading should change to 2. 

3. Press VIEW DIFF. The LCD switch reading should change to 3. 

4. Press STORE. The LCD switch reading should change to 4. 



5. Rotate NOISE FILTER counterclockwise to VERT SET REF. The switch 
reading on the display should be 5. 

6 . Slowly rotate this control clockwise to its far stop. Each position should 
increase the switch reading one count, starting at 5 and ending with 14. 



1502B MTDR Service Manual 



6-5 



Calibration 



7. Rotate DIST/DIV counterclockwise to its far stop. The switch reading on the 
display should be 15. 

8. Slowly rotate this control clockwise to its far stop. Each position should 
increase the switch reading one count, starting at 15 and ending with 25. 

9. The display should currently show a Vp of 0.30. Slowly rotate the left Vp control 
to full clockwise. Each click should correspond to the front-panel control 
setting. 

10. Rotate the right Vp control to full clockwise. Again, the LCD reading should 
match the front-panel control setting. The final reading with both controls fully 
clockwise should be 0.99. 



Front Panel Diagnostic, test all switches. 

Hold down MENU button to Exit. 

Switch: 1 temp: 84 

Vp: 0.30 ◄ 

<> Control 142 



v Control 



Vertical Scale 



0 

181 

24 



Vp Reading 



Figure 6-7: Front Panel Diagnostic Display 

11. Rotate the POSITION control, slowly in either direction. The bar graph 
shown on the display represents the two elements of each control. The readings 
to the right of the bar graph represent numbers used by the instrument to 
calculate the position of the knob. As the control is rotated, these values and the 
bar graph will change. The lower value in each column should be between 0 and 
10 while the higher number is between 245 and 255. 



Front Panel Diagnostic, test all switches. 
Hold down MENU button to Exit. 

Switch: 35 temp: 82 

Vp: 0.99 
<> Control 



Vertical Scale 



0 



v Control 



12 

172 



181 



Corresponding 

Numbers 

Bar Graph 



Figure 6-8: Front Panel Diagnostic Display 



6-6 



1502B MTDR Service Manual 



Calibration 



12. Rotate the ^POSITION control slowly in either direction. The lower value in 
each column should be between 0 and 10 while the higher number is between 
245 and 255. 

13. Rotate the VERT SCALE control slowly in either direction. The lower value 
in each column should be between 0 and 10 while the higher number is between 
245 and 255. 



Thermistor There is a numerical reading from the thermistor located on the LCD. If it is not 
operating properly, the LCD heater might not come on in cold environments. This 
could result in slow or unreadable displays. 

1. The displayed temperature reading should be between 50 and 90, depending on 
the ambient temperature. If the thermistor is defective, the reading will be near 
0 or 255. 



FrontPanel Diagnostic, testall switches. 

Hold down MENU button to Exit. 

Switch: 1 temp: 78 M 

Vp: 0.30 

<> Control 142 



v Control 



Vertical Scale 



0 

181 

24 



Temperature 

Reading 



Figure 6-9: Front Panel Diagnostic Display 

2. Press MENU repeatedly until the instrument returns to normal operation. 

Conclusion If any of the controls or functions are defective or indicate erratic response, the 
function affected by that control could be in error. The defective control should be 
replaced. See the Maintenance chapter of this manual. 



Horizontal Scale (Timebase) Check 

If the instrument fails this check, it must be repaired before any distance 
measurements are made with it. 



1. Set the front-panel controls: 



CABLE 
NOISE FILTER 
VERT SCALE 
DIST/DIV 
V P 



No connection (see text) 

1 avg 

500 mp 

.1 ft/div 

.66 



1502B MTDR Service Manual 



6-7 



Calibration 



2. Turn on the instrument. The display should look very similar to Figure 6-10. 




Figure 6-10: Waveform on the Display with No Cable Attached 



3. Press STORE. 

4. Connect the 3-ft precision test cable to the front-panel CABLE connector. 

5. Press VIEW DIFF. 

6. Rotate NOISE FILTER to HORZ SET REF. The display should look like Figure 
6 - 11 . 




7. Using the <l> POSITION control, set the cursor on the rising edge of the 
waveform at the first graticule up from the centerline. 

8. Press STORE. 



6-8 



1502B MTDR Service Manual 



Calibration 



ac 












0.108 ft 
























1 








/ 

/ 




















✓ 






































i"" 
























o 
< 
I CD 


curso 


»r 

J 


0 r 

1 _ _ 


efere 


nee c 


md P 


ress 


STOI 


3E 



Figure 6-12: Cursor on Rising Edge of Pulse 

9. Rotate NOISE FILTER back to 1 avg. 

10. Press STORE. The front panel reference has now been set. 



ac 












0.000 ft A 


1 . . . . 






















1 





































































































































Figure 6-13: Cursor at 0.000 ft A 



11. Rotate the <ll> POSITION control to the rising edge of the waveform, one 
graticule above the centerline. This measures the distance from the set point to 
the end of the 3-ft cable. The measured distance should be between 2.87 and 
3.13 feet. 



ac 












2.988 ft A' 
























1 










/ 


















/ 


/ 







































































































Figure 6-14: Cursor on Rising Edge of Pulse 

12. Remove the 3-ft cable and connect the 50Q terminator. 



1502B MTDR Service Manual 



6-9 



Calibration 



13. Set the DIST/DIV control to 200 ft/div. 

14. Rotate the <ll> POSITION control clockwise until the display distance window 
shows a distance greater than 2,000.000 ft. The waveform should remain flat 
from zero to this distance. 



ac 








2043.000 ft A 


1 . . . . 


















1 













































































































Figure 6-15: Flatline Display to >2,000 ft 



NOTE. If the Timebase does not appear to be working properly, refer to the Circuit 
Descriptions chapter and the Troubleshooting section of the Maintenance chapter 
of this manual. 



Zero Offset Check 



If the instrument fails this check, you might still make some tests, but the offset 
might change when cable conditions change. 

1. Set the front-panel controls: 

CABLE (see * below) 

NOISE FILTER 1 avg 

VERT SCALE 500 mp 

DIST/DIV .2 ft/div 

V P .99 

POWER ON 

* Nothing should be connected to the front panel CABLE connector. 

2. Adjust the <II> POSITION control so the distance window reads -2.000 ft. 

3. Use the y POSITION control to center the baseline before the incident pulse. 

4. Increase VERT SCALE to 10 mp, using the ^POSITION control to keep the 
baseline centered on the display. 



6-10 



1502B MTDR Service Manual 



Calibration 




5. The front panel CABLE connector has a shorting bar that shorts the input when 
a cable is removed. Attach the 3-ft precision cable to the CABLE connector to 
defeat this shorting bar. 

6. Notice any minor changes in the waveform. The waveform prior to the leading 
edge might change shape slightly, but should not shift more than one division. 




Figure 6-17: Incident Pulse at -2.000 ft with 3-ft Cable Connected 

Max Hold can be used to easily monitor any changes, as shown below. 



ac 












-2.000 ft 

























1 

? 

? 

? 

Figure 6-18: Incident Pulse at -2.000 ft with Max Hold 

7. Turn the instrument OFF, then ON again. This will reset it for the next check. 




1502B MTDR Service Manual 



6-11 



Calibration 



NOTE. If the instrument fails this check,, first refer to Zero Offset Adjust in the 
Adjustment Procedures section of this chapter. If you are unable to adjust this 
satisfactorily, refer to the Circuit Descriptions chapter and the Troubleshooting 
section of the Maintenance chapter of this manual. 



Vertical Position (Offset) Check 

If the instrument fails only this check, it can be used but should be serviced. Not all 
waveforms will be viewable at all gain settings. 



1. Set the front-panel controls: 



CABLE 
NOISE FILTER 
VERT SCALE 
DIST/DIV 
V P 



3-ft precision cable 

1 avg 

500 mp 

1 ft/div 

.99 



2. Set the <l> POSITION control so the distance window reads -2.000 ft. 

3. Using the ^ POSITION control, verify that the entire waveform can be moved 
upward past the center graticule line. 




4. Using the ^ POSITION control, verify that the entire waveform can be moved 
to the very bottom of the display. The top of the pulse should be lower than the 
center graticule line. 



6-12 



1502B MTDR Service Manual 



Calibration 



ac 










-2.000 ft : 




















1 : 


















































































...J 


r 
















J 






1 



Figure 6-20: Waveform at Bottom of the Display 



5. Remove the 3-ft precision cable. 

6. Connect the 50Q terminator to the CABLE connector. 

7. Center the pulse in the display. The pulse should be two divisions high. 




NOTE. If the instrument fails this check, refer to the Troubleshooting section of the 
Maintenance chapter of this manual. 



Noise Check 



If the instrument fails this check, it might still be usable for measurements of large 
faults that do not require a lot of gain. A great deal of noise reduction is available 



with the NOISE FILTER control. 



1. Set the front-panel controls: 



CABLE 
NOISE FILTER 
VERT SCALE 
DIST/DIV 
V P 



50Q terminator 
1 avg 
500 mp 
10 ft/di v 
.99 



1502B MTDR Service Manual 



6-13 



Calibration 



2. Turn the <ll> POSITION control until the distance window reads 100.000 ft. 



ac 








100.000 f 


t 


1 . . . . 


















1 













































































































Figure 6-22: Cursor Moved to 100.000 ft 



3. Change DIST/DIV to 0. 1 ft/div. 

4. Using the VERT SCALE control, set the gain to 5.00 mp/div. 

5. Use the ^ POSITION control to keep the waveform centered on the display. 




6. Press MENU. 

7. Using the ^POSITION control, scroll to Diagnostics Menu. 

8. Press MENU again. 

9. Using the same procedure, select Service Diagnostic Menu, then Noise 
Diagnostic. 

10. Read the results on the display. 



6-14 



1502B MTDR Service Manual 



Calibration 



Noise Diagnostic 
Continuous Result Update 

Acceptable Range Result 

0 - 11 Pixels 4 

vertical scale at 5.00 mp 
and cursor at location to sample. 

- Push MENU button to Exit- 



Figure 6-24: Noise Diagnostic Display 



NOTE. If the instrument does not meet this specification, refer to the Circuit 
Descriptions chapter and the Troubleshooting section of the Maintenance chapter 
of this manual. 



11. Press MENU once to return to the Service Diagnostic Menu. Do not exit from 
the Service Diagnostic Menu because you will use it in the next check. 



Sampling Efficiency Check 

If the instrument fails this check, the waveforms might not look normal. If the 
efficiency is more than 100%, the waveforms will appear noisy. If the efficiency is 
below the lower limit, the waveform will take longer (more pixels) to move from 
the bottom to the top of the reflected pulse. This smoothing effect might completely 
hide some events that would normally only be one or two pixels wide on the display. 

1. While in the Service Diagnostic Menu , select the Sampling Efficiency 
Diagnostic and follow the directions shown on the display. 



Exit Service Diagnostic Menu 
Sampling Efficiency Diagnostic 
Noise Diagnostic 
Impedance Diagnostic 
Offset/Gain Diagnostic 
RAM/ROM Diagnostics 
Timebase is: Normal - Auto Correction 

Move 0 Position to select, then push MENU button 



Figure 6-25: Service Diagnostic Menu 



1502B MTDR Service Manual 



6-15 



Calibration 



2. Press MENU once to return to the Service Diagnostic Menu. Do not exit from 
the Service Diagnostic Menu because you will use it in the next check. 



NOTE. If the instrument does not pass this check, refer to the Circuit Descriptions 
chapter and the Troubleshooting section of the Maintenance chapter of this manual. 



Offset/Gain Check 



If the instrument fails this check, it should not be used for loss or impedance 
measurements. 

1. While in the Service Diagnostic Menu, select the Offset/Gain Diagnostic and 
follow the directions shown on the display. 



Exit Service Diagnostic Menu 
Sampling Efficiency Diagnostic 
Noise Diagnostic 
Impedance Diagnostic 
Offset/Gain Diagnostic 
RAM/ROM Diagnostics 
Timebase is: Normal - Auto Correction 

Move 0 Position to select, then push MENU button 



Figure 6-26: Service Diagnostic Menu 



NOTE. The 48 dB step might fail intermittently. If a more accurate reading is desired, 
TP9041 on the Main Board or TP3051 on the Driver/Sampler Board must be 
grounded during the check. See the Maintenance chapter for the case and EMI 
shield removal instructions. 



2. There are five screens of data presented in this diagnostic. The Pass/Fail level 
is 3% for worst case. 

3. Press MENU once to return to the Service Diagnostic Menu. Do not exit from 
the Service Diagnostic Menu because you will use it in the next check. 



RAM/ROM Check 



If the instrument fails this check, various functions might be affected. Without the 
RAM/ROM functions operating correctly, it is doubtful you would have gotten this 
far. This check will give you assurance that the RAM/ROM circuits are operating 
properly. 



6-16 



1502B MTDR Service Manual 



Calibration 



1. In the Service Diagnostic Menu, select the RAM/ROM Diagnostics. 



Exit Service Diagnostic Menu 
Sampling Efficiency Diagnostic 
Noise Diagnostic 
Impedance Diagnostic 
Offset/Gain Diagnostic 
RAM/ROM Diagnostics 
Timebase is: Normal - Auto Correction 

Move 0 Position to select, then push MENU button 



Figure 6-27: Service Diagnostic Menu 

2. Press MENU. The diagnostic is automatic and will display the result on the 



3. Turn the instrument off, then on again. This will reset it for the next check. 



NOTE. If the instrument fails any of the last three checks , refer to the Circuit 
Descriptions chapter and the Troubleshooting section of the Maintenance chapter 
of this manual. 



If the aberrations are out of spec, the ohms-at-cursor function might be less accurate 
than specified. 

1. Set the front-panel controls: 



2. Using the POSITION control, adjust the distance window to read -2.000 ft. 



LCD. 



Aberrations Check 



CABLE 
NOISE FILTER 
VERT SCALE 
DIST/DIV 
V P 



50Q terminator 
1 avg 
500 mp 
5 ft/div 
.99 



1502B MTDR Service Manual 



6-17 



Calibration 



ac 










-2.000 ft 






















.... 






















IL 













































































































Figure 6-28: Waveform with Cursor at -2.000 ft 



3. Increase DIST/DIV to 50 mp/div. 

4. Center the pulse on the display, keeping the trailing baseline on the center 
graticule 




5. Set the DIST/DIV control to 0.2 ft/div. 

6. Adjust the <1> POSITION control until the rising edge of the pulse is in the 
left-most major division on the display. 

7. Move the cursor to 0.000 ft with the ^ POSITION control. All the aberration 
except the one under the cursor should be within one division of the center 
graticule line (see Figure 6-30, next page). 



6-18 



1502B MTDR Service Manual 



Calibration 



0 

i 

i: 
t: 

Figure 6-30: Waveform at 5 mp/div 

8. Increase the DIST/DIV to 200 ft/div. 

9. Increase the VERT SCALE to 5.00 mp. 

10. Verify the the waveform is flat ± one minor division after the incident step. 

NOTE. If the instrument fails this check, refer to Driver/Sampler in the Circuit 
Descriptions chapter and the Troubleshooting section of the Maintenance chapter. 




Risetime Check 



If the risetime is out of specification, it might be difficult to make accurate 
short-distance measurements near the front panel and might affect the resolution of 
the instrument. 



1. Set the front-panel controls: 



CABLE 
NOISE FILTER 
VERT SCALE 
DIST/DIV 
V P 



50Q terminator 
1 avg 
500 mp 
0.1 ft/div 
.99 




1502B MTDR Service Manual 



6-19 



Calibration 



2. Use the <ll> POSITION control to move the incident pulse to the center of the 
display (as shown in Figure 6-31). 

3. Turn the VERT SCALE control clockwise until the leading edge of the incident 
pulse is five major divisions high (about 200 mp). 

4. Position the waveform so that it is centered horizontally and vertically on the 
middle graticule lines (2.5 divisions below the center horizontal graticule line 
and 2.5 divisions above). 




Figure 6-32: Incident Pulse Centered, Vertical Increased 

5. Turn the NOISE FILTER control to HORZ SET REF. 



6. Using the <ll> POSITION control, set the cursor to the point where the lower 
portion of the pulse’s rising edge first crosses a major horizontal graticule line 
(should be about half a division from the bottom of the pulse). 



7. Press STORE. 

8. Turn the NOISE FILTER to 1 avg. 




Figure 6-33: Cursor on Rising Edge at First Horizontal Graticule 

9. Using the <ll> POSITION control, set the cursor to the point where the upper 
portion of the pulse’s rising edge crosses a major horizontal graticule line 
(should be about half a division from the top of the pulse). 



6-20 



1502B MTDR Service Manual 



Calibration 



10. Verify that the distance is less than or equal to 0.096 ft A. 




Figure 6-34: Cursor on Rising Edge at Last Horizontal Graticule 



NOTE. If the instrument fails this check, refer to Troubleshooting in the Maintenance 
chapter and Driver/Sampler in the Circuit Descriptions chapter of this manual. 



Jitter Check 



NOTE. If you have just completed the previous check, the instrument might still be 
in HORZ SET REF mode. This will not have any effect on the Jitter Check. If you 
wish to exit HORZ SET REF, either turn the power off and on, re-initializing the 
instrument, or follow the directions for HORZ SET REF in the Operator chapter. 



1. Set the front-panel controls: 



CABLE 
NOISE FILTER 
VERT SCALE 
DIST/DIV 
V P 



50Q terminator 
1 avg 
500 mp 
.1 ft/div 
.99 



2. Using the POSITION and the ^POSITION controls, center the rising edge 
of the pulse on the center horizontal graticule line. 



1502B MTDR Service Manual 



6-21 



Calibration 



1 

?! 

?! 

Figure 6-35: Rising Edge at Center of Display 

3. Turn the VERT SCALE control clockwise for a reading of more than 
1.0 mp/div. 

4. Verify that the leading edge of the pulse moves less than five pixels (0.02 ft). 




ac 










-1.316 ft 






















.... 

























































































































Figure 6-36: Rising Edge with Scale at 1.0 mp/div 



You may also use the Max Hold function found in the Acquisition Control menu, 
within the Setup menu. This function can simplify this measurement for you by 
displaying jitter accumulating. See the Operator chapter for directions on using Max 
Hold. 



ac 










- 1.316 ft : 






















.... 

























































































































Figure 6-37: Rising Edge with Max Hold on 



6-22 



1502B MTDR Service Manual 



Calibration 



Option 03: Battery Pack Check 

Look in this chapter under Power Supply Checks and Adjustments for battery and 
charging circuit information. 



Option 04/07: YT-1/YT-1S Chart Recorder Check 

If the instrument does not pass this check, chart recordings might not be possible. 

1. Access the Chart Diagnostics Menu found under the Diagnostics Menu. 

2. Scroll to Head Alignment Chart and follow the directions. 

3. Press MENU to exit this diagnostic. 




Figure 6-38: Head Alignment Chart Print 



4. There should be approximately six inches of narrow-spaced lines and six inches 
of wide- spaced lines. The total length of both should be between 10.87 and 
12.76 inches. Fold the paper at the last narrow-spaced line and the two ends 
should be of equal length (half narrow, half wide). 



NOTE. If the chart recorder does not pass this check, refer to the YT-1/YT-1S Chart 
Recorder Instruction Manual (07 0-627 0-xx) for service information. 



Option 05: Metric Default Check 

Option 05 requires no check other than to turn on the instrument and see if it displays 
in meters. Instructions for changing the default can be found in the Maintenance 
chapter of this manual. 



1502B MTDR Service Manual 



6-23 



Calibration 



Adjustment Procedures 



Equipment Required 



Equipment 


Performance Required 


Example or Tek P/N 


Digital Multimeter 


Range: 0 to 200 VDC 


DM501A or equivalent* 


Ohmmeter 


Resolution to 0.01Q 


DM501A or equivalent* 


Variable AC Source 


with power meter 


GenRad W10MT3W orequiv. 


Variable DC Power Supply 


Oto 14 VDC, 3 A 




3-foot Coaxial Cable 


50Q 


012-1350-00 



* must be plugged into power mainframe 



Metric Instruments Metric default timing is made by moving a jumper on the back of the Front Panel 
Board (see Maintenance chapter of this manual). To make the calibration easier, this 
jumper will be moved to the standard timing position during calibration, then moved 
back to the metric position when calibration is completed. 



Before Starting On early instruments, there is an adjustment on the Main Board used for timebase 
compensation, identified as R2034. Because of a slight crosstalk effect between 
circuits, measurements of a certain length cable would show a small glitch. This 
adjustment eliminated the problem and subsequent improvements in circuit board 
design eliminated the need for the adjustment. If your instrument has this 
adjustment, it has been set at the factory and requires no further attention. 



Power Supply Module 




6-24 



1502B MTDR Service Manual 



Calibration 



Remove the Case and EMI To perform the Adjustment Procedure, the instrument must be removed from the 
Shields case and the EMI shields removed. Instructions on both procedures are located in 
the Maintenance chapter of this manual. 



Visual Inspection 



If any repairs are made to the instrument, or if it has been disassembled, we 

recommend a visual inspection be made. 

1. Check all screws for tightness and that the screw heads are not burred or 
rounded. 

2. Set the line voltage switch on the rear panel to 110V and check for the proper 
fuse (0.3 A). 

3. Check if the LCD has been cleaned on the outside and the implosion shield of 
the front panel has been cleaned on the inside. 

4 . Check that the knobs and buttons work properly. The NOISE FILTER, 
DIST/DIV, and both Vp knobs have detents; all others should rotate smoothly. 
Check that the knobs are tight (no loose set screws). Check that the set screw 
on the POWER switch shaft is tight. 

5. Check the cables for proper connection polarity and tightness. Make sure the 
cables on the front of the Main Board come down from the plug into the 
instrument instead of curving toward the outside. All cables should have the 
exposed ends away from the metal chassis. 

6. If any components were replaced by soldering, check for solder balls, excess 
flux, and wire clippings. Good soldering practices must be followed when 
repairing this instrument. 



Power Supply Checks and Adjustments 

Power-Up Procedure 

1. Set the front-panel controls: 

NOISE FILTER 1 avg (3rd stop CW) 

DIST/DIV 1 ft/div (4th stop CW) 

V P .99 

2. Make sure the POWER switch is in the OFF position. 

3. Connect the 115 VAC output of the Variac® into the AC socket on the rear of 
the 1502B. 



1502B MTDR Service Manual 



6-25 



Calibration 



Voltage Checks 

1. Pull the POWER switch to the ON position. 

2. Observe that the power draw does not exceed 4 Watts on the Variac. 




3. Connect the positive (+) voltmeter probe to TP1020 (+16.6 VDC - it might be 
marked as 15.8 V on some older power supplies). 

4. Connect the negative (-) probe to TP 1010 (ground). 




Figure 6-41 : Power Supply Test Points TP1020 and TP1010 



6-26 



1502B MTDR Service Manual 



Calibration 



5. Verify that the supply voltage is 1 6.6 VDC and there is a minimal current drawn 
(< 2W) from the Variac. 

6. Connect the positive (+) voltmeter probe to TP2030. The negative (-) voltmeter 
probe should remain connected to ground. The reading should be +16.2 VDC 
(see following table for tolerances). 




Figure 6-42: Power Supply Test Point TP2030 



Supply 


Range 


Test Point 


Location 


+16.2 VDC 


+15.9 to +16.4 VDC 


TP2030 


Power Supply Board 


+5.0 VDC 


+4.85 to +5.25 VDC 


Pin 1, J 5040 


Main Board 


-5.0 VDC 


-4.85 to -5.25 VDC 


Pin 3, j 5040 


Main Board 


+15.0 VDC 


+14.7 to +15.3 VDC 


Pin 4, j 5040 


Main Board 


-15.0 VDC 


-14. .7 to -15.3 VDC 


Pin 6, J 5040 


Main Board 



7. Make a mental note of the location where the ribbon cable from the power 
supply is plugged into the Main Board, then turn the instrument over. 



NOTE. When the instrument is turned over, you will be looking at the top ( component 
side ) of the Main Board. 



The J5040 pins go through the circuit board and appear on the top (component side) 
of the Main Board. J5040/P5040 is the input from the power supply. The other end 
of the cable is J1030/P1030 on the Power Supply Board. Measure the voltages on 
the pins listed in the table and verify the supply voltages. 



1502B MTDR Service Manual 



6-27 



Calibration 



Range Check 




Connector plug P5040 Connector pin J5040 

on bottom of Main Board. on top of Main Board. 



Figure 6-43: Connector Plug P5040 and Pins J5040 on Bottom of Main Board 



Test points in this check are located on the Power Supply Board. 

1. Connect the positive (+) probe to the +16.6 VDC supply (TP1020) on the Power 
Supply Board. 




Figure 6-44: Power Supply Test Point TP1020 

2. Change the AC output voltage on the Variac to 132 VAC. 

3. Verify that the +16.6 VDC supply remains regulated (+16.4 to +16.8 VDC). 

4. Reduce the Variac output voltage to 90 VAC. 

5. Verify that the +16.6 VDC supply is still regulated (+16.4 to +16.8 VDC). 

6. Move the positive (+) probe to the +16.2 VDC supply (TP2030) 

7. Reduce the Variac output voltage until the + 1 6.2 VDC (and the instrument) shut 
down. This voltage must be lower than 90 VAC. 



6-28 



1502B MTDR Service Manual 



Calibration 




Figure 6-45: Power Supply Test Point TP2030 



8. Raise the Variac output voltage to 120 VAC. The instrument should remain shut 
down. 

9. Turn the 1502B POWER off. 

Main Board ± 12 VDC Check and Adjust 




+1 2 VDC Test points in this check are located on the Main Board. 

1. Turn the instrument over to access the Main Board. 

2 . Attach the positive (+) probe from the voltmeter to the + side (facing the edge 
of the board) of C9031. 

3 . Attach the negative (-) probe to the other side of C9035. 

4 . Turn the instrument POWER on and check that less than 4 Watts is drawn from 
the Variac. 

5. Adjust R9032 for +12.0 VDC. 



1502B MTDR Service Manual 



6-29 



Calibration 




Figure 6-47: Main Board Probe Points 



-1 2 VDC Test points in this check are located on the Main Board. 

1. Move the positive (+) probe to the ground side of C9035 (the side away from 
the edge of the board). 

2. Verify that the voltage is -11.8 to -12.2 VDC. 

3. Verify that the LCD shows the following display: 



ac 










0.000 ft 


1 . . . . 


















1 






































r 


\ 
















1 


V 



















































Figure 6-48: Waveform on Display 

You might have to adjust R1018 (Contrast Adjust) on the Front Panel Board to get 
a clear display (see LCD Check and Adjustments in this section). 

DC Power Check 

1. Turn the POWER off. 

2. Remove the AC plug from the rear panel of the instrument. 



6-30 



1502B MTDR Service Manual 



Calibration 



3. Connect an external 12 VDC power supply into the battery port jacks. Make 
sure you observe proper polarity. The positive side of the battery pack port is 
next to the Power Supply Board. The negative side is next to the Driver/Sampler 
Board. 

4. Adjust the external 12 VDC supply for +11.5 VDC output at the terminals of 
the battery input. 

5. Connect a DC ammeter in series with the positive (+) side of the 1 2 VDC supply. 
The current measurement must not exceed 350 mA. 




The following test points are located on the Power Supply Board. 




Figure 6-50: CR2012 on Power Supply Board 



1502B MTDR Service Manual 



6-31 



Calibration 



6. Connect the positive (+) probe of the voltmeter to the front side of CR2012 on 
the Power Supply Board (this is the large diode next to J2010. The positive 
probe should be on the non-banded end). 

7. Connect the negative (-) probe to ground. 

8. Turn the 1502B POWER on. The instrument should initialize and go into 
normal operation. The display will be normal except ac in the upper left corner 
will have changed to bat. 




Figure 6-51 : Display Showing Power is Battery 

9. Reduce the output voltage of the DC power supply until bat/low appears in the 
upper left corner of the display. 




Figure 6-52: Display Showing Battery Voltage is Low 



10. Verify that the DC supply voltage is between 10.6 and 11.0 VDC. 

11. Remove the voltmeter probes from the 1502B. 

12. Remove the external 12 VDC power supply cable from the battery pack port. 

13. Connect the AC supply cord to the rear panel. 



6-32 



1502B MTDR Service Manual 



Calibration 



Charging Current Check 



(with optional battery pack) 

The following test points are located on the Power Supply Board. 

1. Turn the POWER off. 

2 . Plug the optional battery pack into the battery pack port. 

3. Connect a voltmeter across the 4Q resistor, R2012, located on the Power Supply 
Board. 




4 . Connect the positive (+) probe to the side nearest the front panel and the 
negative (-) probe to the other end. 

The voltage drop across R2012 should be between 0.4 VDC and 1.2 VDC. 

5. Turn the POWER on. 

The voltage reading across R2012 should change only slightly ( ± 10 mV). 



NOTE. The charging current will vary according to the level of charge already on 
the battery. With a fully charged battery, the voltage across R2012 should be 
approximately 0.4 VDC. With a battery below 11 Volts, R2012 should read 
approximately 1.2 VDC. 



1502B MTDR Service Manual 



6-33 



Calibration 



Impedance Check 

If the instrument fails this check, it should not be used for loss or impedance 
measurements. 

The following test points are located on the Driver/Sampler Board. 




1. Turn off the POWER to the instrument. 

2. Remove the cover of the Driver/Sampler Board (see Maintenance chapter). 



TP1020 TP 1030 




Figure 6-55: TP1030 on Driver/Sampler Board 



6-34 



1502B MTDR Service Manual 



Calibration 



3. Using a precision Ohmmeter, measure the resistance from the 0.6 VDC supply 
(TP 1030) to the center conductor of the front-panel CABLE connector. 

4. Subtract the resistance of the Ohmmeter test probes. The result should be 
between 49.5 Q and 50.5 Q. 

LCD Check and Adjustment 

1. Turn POWER on. 

2. Push MENU. 

3. Using the ^POSITION control, scroll to Diagnostics Menu. 

4. Push MENU. 

5. Scroll to LCD Diagnostics Menu. 

6. Push MENU. 

7. Scroll to LCD Alignment Diagnostic. 

8. Push MENU. 




Figure 6-56: R1018 on Front Panel Board 



9. Observe the LCD as you adjust R1018 (Contrast Adjust) counterclockwise until 
the entire pattern starts to dim. 




Figure 6-57: LCD Pattern with Contrast Too Light 



1502B MTDR Service Manual 



6-35 



Calibration 




Figure 6-58: LCD Pattern with Contrast Too Dark 

10. Turn R1018 clockwise until the entire pattern is clear and sharp. 



Push MENU 1 sec to alternate, 2 secs to quit 



Figure 6-59: LCD Pattern Adjusted for Sharpness 

11. Press MENU once quickly. The ON pixels will be toggled off and the OFF 
pixels will be toggled on. Watch to see if all the pixels are being activated. 

12. Once contrast has been set using the LCD pattern, verify it with a normal 
waveform display. 

a. Ensure that the instrument has been at 75° F ± 5° F (25° C ± 3° C) for at 
least one hour (operating or non-operating). 

b. Turn the instrument on and allow it to warm up for at least five minutes. If 
the instrument was already on (e.g., you are performing this adjustment 
immediately after steps 1-11), then cycle the power off, then back on again 
to return it to default settings. 

c. While a waveform is on the display, adjust R1018 on the Front Panel Board 
counterclockwise until most of the display has dimmed. 



6-36 



1502B MTDR Service Manual 





Calibration 




Figure 6-60: Waveform with Contrast Too Light 

d. Start rotating R101 8 slowly clockwise until all of the pixels are just visible 
on the display. If you go too far, restart the adjustments at step c. 

e. Rotate RIO 18 one quarter turn clockwise past the point of step d. 



NOTE. It is important to always determine the proper contrast setting by coming 
from a faded display. It takes a higher threshold voltage to turn a pixel on than it 
does to turn one off. If it is done from the other direction, the display will be too 
bright. 



f. Inspect the display for any bleeding (areas that are too dark) or any fading 
(areas that are too light). 

g. Turn the instrument off. 

h. After waiting a few seconds, turn the instrument back on. 

i. Reinspect the display for bleeding or fading. 

j. Readjust R1018 if necessary. 




Figure 6-61 : Waveform with Contrast Adjusted Correctly 



1502B MTDR Service Manual 



6-37 



Calibration 



If the Contrast Adjust is set properly, you will be able to see the cursor clearly when 
it is moved rapidly across the display. If any residual images are made by the cursor 
movement, they should fade out quickly. 



NOTE. If you are unable to adjust the contrast, or if pixels are not functioning, see 
the Troubleshooting section in the Maintenance chapter of this manual. 



Zero Offset Adjust 



The following adjustment is located on the Driver/Sampler Board. 




1. Turn off the POWER to the instrument. 



2. Remove the EMI shield covering the Driver/Sampler Board (see Maintenance 
chapter). 

3. Turn the POWER on. 



4 . Adjust the ^ POSITION control until the distance window reads -2.000 ft. 

5. Adjust the ^POSITION control to center the baseline on the center horizontal 
graticule line (see Figure 6-63, next page). 

6. Set the front-panel controls: 



CABLE 

NOISE FILTER 
VERT SCALE 
DIST/DIV 
V P 



no connection 
1 avg 
10 mp 
0.2 ft/div 
.99 



6-38 



1502B MTDR Service Manual 



Calibration 




7. If necessary, readjust the ^POSITION control to center the baseline on the 
center horizontal graticule line. 

8. Attach the 3-foot precision cable to the front-panel CABLE connector. This will 
probably cause the waveform to move slightly on the display. 

9. Adjust R1042 (Zero Offset) to move the waveform to the same position as when 
no connector was attached to the front panel. 





Figure 6-64: R1042 on Driver/Sampler Board 



10. Remove the 3-foot precision cable. 

11. Verify that the waveform moves less than 0.5 division. 



1502B MTDR Service Manual 



6-39 




Calibration 



NOTE. Some changes in shape of the baseline before the leading edge is normal. If 
this measurement is difficult to make, access the Service Diagnostic Menu and 
change the timebase mode from Timebase is:Normal - Auto Correction to Timebase 
is: Diagnostic - No Correction. This will give more stability to the pulse when the 
cable is connected. 



12. Turn the instrument off. 

13. Replace the Driver/Sampler EMI shield. Be sure the ribbon cable is placed in 
the center slot of the shield so it won’t be crushed by the shield. 



After Adjustments are Completed 

1. If the instrument is Option 05 (metric), refer to the Maintenance chapter to 
return the metric default jumper to its proper position. 

2. Reinstall the 1 502B in its case (refer to the Maintenance chapter of this manual). 
Care should be taken to follow the directions to maintain watertight integrity 
of the case. 

3. Turn back to the Calibration section of this chapter and perform all those 
Performance Checks that did not require case-off adjustments. 



6-40 



1502B MTDR Service Manual 



Maintenance 



Introduction 

This chapter contains information on preventive and corrective maintenance, 
troubleshooting, panel control assembly procedures, and shipping instructions. 
Please refer to schematics for physical location of circuits and components. 



NOTE : We recommend that service be performed at an authorized Tektronix Service 
Center or by a technician skilled in sampling and pulse techniques. 



Equipment Required This is a list of common tools needed to accomplish all the maintenance procedures 

that follow: 



5/16" hex nut driver 


Phillips-head screwdriver 


11/32” hex nut driver 


Straight-blade screwdriver 


1/16" hex wrench 


Torque driver 


5/16" open-end wrench 


Soldering and desoldering tools 


7/16" open-end wrench 


Cotton swabs, non-woven wipes 


1/2" open-end wrench 


Isopropyl alcohol, LocTite ®, etc. 



Preventive Maintenance 

Preventive maintenance includes cleaning, visual inspection, and lubrication. A 
convenient time to perform preventive maintenance is during the periodic 
performance check/calibration procedure. If the instrument has been subjected to 
extreme environments or harsh handling, more frequent maintenance might be 
necessary. 



Cleaning 

CAUTION . Do not use chemical agents that contain benzene, toluene, xylene, 
acetone, etc., because of possible damage to plastics in the instrument. 




The exterior case and front panel should be washed gently with mild soap and water. 

The faceplate in front of the LCD should be cleaned gently with Kendall Webril 
non-woven wipes (Tek P/N 006-0164-00), or equivalent, moistened with isopropyl 
alcohol. 



1502B MTDR Service Manual 



7-1 




Maintenance 



The interior of the 1502B is protected from dirt and dust as long as the option port 
and case are intact. However, if interior cleaning is necessary, blow off accumulated 
dust with low-pressure air and remove the remaining dirt with a soft brush, cotton 
swab, or pipe cleaner moistened with isopropyl alcohol. 



Lubrication All the switches and potentiometers on the 1502B are sealed from external 
contaminants and, therefore, require little maintenance and no lubrication. 
Occasionally, blowing out accumulated dust is all that is needed. 

Visual Inspection Obvious defects, such as broken connections, damaged boards, frayed cables, 
improperly seated components, and heat-damaged components should be corrected 
first before attempting further troubleshooting. Heat damage usually indicates a 
deeper problem somewhere in the circuitry and should be traced and corrected 
immediately. 

We do not recommend electrical checks of individual components because defective 
components will become evident during instrument operation. 



Recalibration After maintenance has been performed, the instrument should be checked as per the 
procedures in the Calibration chapter of this manual. 



Part Removal and Replacement 

AC Fuse The fuse is accessible through the rear panel of the case. 
1. Unscrew the fuse cover and remove. 




Figure 7-1 : Location of Voltage Selector and Fuse Holder on Rear Panel 



7-2 



1502B MTDR Service Manual 



Maintenance 



2 . Use a straight-blade screwdriver to remove the fuse holder. 

3 . Check the voltage selector for proper voltage setting. If the instrument voltage 
selector is set for 115 VAC, replace the fuse with a 0.3 A fuse (Tek P/N 
159-0029-00). If the voltage selector is set for 230 VAC, replace the fuse with 
a 0.15 A fuse (Tek P/N 159-0054-00). 

4 . Replace the fuse holder. 

5 . Replace the access cover. 

Removal of Case and EMI 
Shields 

1. Remove the instrument front cover. 

2 . If installed, remove the battery pack from the back of the instrument. 

3 . If installed, remove the chart recorder, or other device, from the option port. 

4 . Loosen the four screws on the back of the case and set the instrument face-up 
on a flat surface. 

5 . Swing the handle out of the way of the front panel. 

6. Break the chassis seal by pushing downward with both hands on the handle 
pivots on each side of the case.. 

7 . Grasp the case with one hand and tilt the chassis out with the other. Lift by 
grasping the outside perimeter of the front panel. 



CAUTION. Do not lift the instrument by the front-panel controls. The controls will 
be damaged if you do so. 



8. Remove the screws holding the shields to the back frame. 

9 . Remove the screw in the middle of the bottom EMI shield. 

10 . Remove the EMI shields from the top and bottom of the chassis by carefully 
running a straight-blade screwdriver between the shield and the groove in the 
chassis rail. 




Checking Desiccant 
Cartridge 
(SN < B037562 only) 



Check the desiccant cartridge mounted on the rear of the chassis, inside the case. If 
the crystals of silica seen through the window of the cartridge are blue, the 
dehydrating agent is active and no further maintenance is required. 



1502B MTDR Service Manual 



7-3 



Maintenance 




Rejuvenating the 
Desiccant Cartridge 
(SN < B037562 only) 



CAUTION. In a humid environment, it is imperative that the desiccant be checked to 
see if it is active. High humidity within the instrument can cause component damage, 
including the LCD. 

Use caution when disassembling the instrument in a high humidity environment. 
Make sure the instrument is reassembled with rejuvenated agent per the 
following instructions. 



If the silica has turned pink, the cartridge must be rejuvenated per the following 
procedure: 



CAUTION. Do not disassemble the cartridge. The drying action of this material 
causes irritation of the mucous membranes of the nose and throat and irritation of 
the skin. Although it is considered non-toxic, avoid ingestion. 

If the material comes in contact with the eyes, wash it from the eyes with large 
amounts of water and seek medical attention immediately. 

If the material comes in contact with the skin, wash with soap and water. 



Figure 7-2: Desiccant Cartridge on Rear of Chassis 

1. Loosen the cartridge hold-down bracket, located on the rear edge of the 
instrument chassis. 

2. Remove the cartridge. 

3. Heat the cartridge in an oven at approximately 350° F until the blue color is 
restored to the crystals. 

4. Place the cartridge in an air-tight moisture-proof container until it is cool. 

5. When cool, replace the cartridge in its brackets. 




7-4 



1502B MTDR Service Manual 



Maintenance 



6. Tighten the retaining bracket. 

Removing the Power 

Supply Module l. From the Power Supply Board, remove the 14-conductor ribbon cable. This is 
a keyed connector, so polarity is guaranteed upon reinstallation (Figure 7-3, 5). 




Figure 7-3: Power Supply Module and P/O Rear Panel 



2. Remove the screw and washer located below the power switch on the instrument 
side panel (Figure 7-3, 7) 

3. Remove the screw and washer holding the power supply module to the bottom 
chassis (Figure 7-3, 4). 



1502B MTDR Service Manual 



7-5 



Maintenance 



Removing the Power 
Supply Board 



Removing the Power 
Transformer 



Removing the Power Cord 
Receptacle 



4 . Remove two screws holding the power supply module to the rear chassis panel. 
One is located near the AC power receptacle and the other is directly above the 
fuse holder (Figure 7-3, 6). 

5. Remove the power supply module from the instrument by moving it toward the 
front of the instrument, guiding the power switch away from the mechanical 
linkage assembly. 



NOTE. The screws identified as 1 hold the circuit board to the module. They should 
not be removed until you are ready to remove this circuit board from the module ( next 
procedure ). 



1. Remove the power supply module per previous procedure. 

2. Remove the two-conductor harmonica connector (Figure 7-3, 3). 

3. Remove the four-conductor harmonica connector (Figure 7-3, 2). 

4 . Remove four screws holding the circuit board to the module (Figure 7-3, 1). 

5 . Remove the Power Supply Board by carefully lifting up. Be sure the large 
capacitor on the bottom of the board clears the two nut blocks on the module 
side panels. If the board or the capacitor binds on either the nut blocks or the 
chassis side panel screw, remove the nut blocks. 

1. Remove the power supply module and circuit board as per previous procedures. 

2. Remove the three screws holding the side panel on the power supply module 

3. Remove the side panel. This will provide access to the transformer. 

4 . Unsolder the six wires attached to the power transformer. 

5 . Unsolder the varistor (R101) from lugs 4 and 5. 

6. Remove the two screws and lock-washers holding the power transformer to the 
chassis. 

7 . Lift out the transformer. 



NOTE. When reassembling , add a small amount ofLocTite® to the two transformer 
mounting screws in step 6. 



1. Remove the power supply module, circuit board, and transformer per previous 
procedures. 



7-6 



1502B MTDR Service Manual 



Maintenance 



Removing the Fuse Holder 
and Voltage Selector 



Power Cord Conductor 
Color Code 



Removing the DC 
(Battery) Banana Plugs 



2. Unsolder the three wires on the filter unit. 

3. Remove the two screws and the spacer holding the receptacle. 

4 . Remove the filter unit from the rear of the module. 

1. Remove the power supply module, circuit board, and transformer per previous 
procedures. 

2. Unsolder all four wires from the voltage selector switch. 

3. Unsolder the two wires from the fuse holder. 

4 . Unscrew the hold-down nuts from both units. 

5. Remove both units from the rear of the module. 



Conductor 


Color 


Alternate Color 


Ungrounded (line) 


Brown 


Black 


Grounded (neutral) 


Blue 


White 


Grounded (earth) 


Green/Yellow 


Green 



1. Remove both nuts from the banana plugs (see Figure 7-4, next page). 

2. Remove the plugs from the power supply module. 



NOTE. During reassembly, be aware that the positive (+) plug is on the side closest 
to the Power Supply Board. The order of parts must be: plug, solder lug (with 
capacitor ), plastic shouldered washer, and on the other side of the chassis wall, the 
mica insulating washer, metal washer, then nut. The negative (-) plug sequence is: 
plug, solder lug ( the other side of the capacitor ), plastic shouldered washer, and on 
the other side of the chassis wall, the nut. 



1502B MTDR Service Manual 



7-7 



Maintenance 




Removing the Main Board 



1. From the top side of the instrument, remove the multi-colored cable (power 
supply) from the Main Board. 

2. Turn the instrument upside down to expose the top of the Main Board. 

3. Remove the three multi-colored cables from the component side of the Main 
Board. This can be accomplished by inserting a small straight-blade 
screwdriver in the key and gently prying the connector from the board. Take care 
to guide the connectors straight off to avoid bending the pins. 

4. Remove the eight screws and the center spacer post (with washer and locknut) 
that fasten the Main Board to the chassis. 

5. Remove the Main Board, taking care to avoid binding on the power switch 
mechanical linkage. 



NOTE. One of the corner screws (see Figure 7-5, next page ) holds a ground strap 
connector. 



7-8 



1502B MTDR Service Manual 



Maintenance 



Elapsed Time Indicator 
(SN <6020511 only) 




If the elapsed time indicator on the Main Board has reached 5,000 hours, it may be 
left in place, replaced, or reversed. If the device is reversed, simply read the hours 
backwards from 5,000 to zero hours. 



i 



Ml 030 









1—1 


~i □ n n n n 








U1030 


HZ 


H 


J u U 1^^ u 



Figure 7-6: Elapsed Time Indicator on Main Board 



Replacement 

1. To replace, unsolder both ends and remove. 

2. Insert a new timer and re-solder. 

Reversal 

1. Unsolder both ends of the timer and remove it from the board. 

2. Reverse the direction it was mounted previously and re-solder. 



1502B MTDR Service Manual 



7-9 




Maintenance 



EPROM Replacement 

1. Use an IC puller that is designed to extract multi-pin microcircuits to remove 
the EPROM from its socket. 




Front of 
Instrument 




Figure 7-7: EPROM on Main Board 

2. When installing a new EPROM, make sure the notch in the IC is facing toward 
the front of the instrument and all pins are inserted correctly in the socket. 



Lithium Battery 
Replacement 



Typically, the lithium battery for the non-volatile memory will last over seven years. 
If it requires replacement, use the following procedure. 




CAUTION. To avoid personal injury, observe proper procedures for handling and 
disposal of lithium batteries. Improper handling might cause fire, explosion, or 
severe burns. Do not recharge, crush, disassemble, heat the battery above 212° F 
(100° C), incinerate, or expose the contents of the battery to water. Dispose of the 
battery in accordance with local, state, and federal regulations. Typically, small 
quantities (less than 20 batteries ) can be safely disposed of with ordinary garbage 
or in a sanitary landfill, but check local regulations before doing this. 



1. Remove the Main Board as described in a previous procedure. 




Figure 7-8: Lithium Battery on Main Board 



7-10 



1502B MTDR Service Manual 




Maintenance 



Removing the 
Driver/Sampler Board 



Removing the Front Panel 
Assembly 



Removing the Display 
Module/Front Panel Board 



2. Unsolder the four leads of the lithium battery, being careful not to overheat the 
cell. 

3. Remove the cell from the Main Board. 

4. Install a new battery and solder the leads to the Main Board. Be sure that the new 
battery is one that is supplied or authorized by Tektronix. An improper 
replacement cell could cause irreversible damage to the Main Board circuitry. 



NOTE. If the instrument is equipped with Option 06, Ethernet Adapter Board, follow 
the instructions under Option 06 in this chapter. There is an illustration in the 
Replaceable Mechanical Parts chapter showing the Option 06 and Driver/Sampler 
Boards. 



1. Remove the two screws and washers holding the cover to the chassis. 

2. Remove the cover by sliding it toward the center of the instrument. When 
re-assembling, make sure the cable is placed under the slot provided. 

3. Disconnect the multi-conductor cable from the circuit board. 

4. Remove the coaxial cable from the circuit board. 

5. Remove the circuit board from the instrument by sliding it out of the card 
guides. 

1. Using a hex wrench, disassemble the power switch linkage. This disconnects 
the front-panel switch shaft from the linkage block. 

2. Remove the three multi-conductor cables from the Main Board. 

3. Remove the Driver/Sampler Board EMI shield. 

4. Remove the coaxial cable from the Driver/Sampler Board. 

5. Remove the four comer screws on the instrument front panel. 

6. Carefully guide the coaxial cable through the Driver/Sampler card cage. 

7. Remove the Front Panel Assembly from the instrument chassis. 

1. Using the previous procedure, remove the Front Panel Assembly from the 
instrument. 

2. Remove all knobs. 



1502B MTDR Service Manual 



7-11 



Maintenance 



3. Remove the hex nuts and washers from the front-panel controls. 

4. Remove the buttons by pressing gently on the rubber boot behind each button. 




CAUTION. Take care not to use a sharp object to remove the buttons because it might 
puncture the rubber boot, thereby subjecting the instrument to moisture/water 
intrusion. 



NOTE. When re-assembling, push the rubber boot down on the switch shaft so that 
the switch button can easily be replaced. 



5. Remove the four screws holding the Display Module/Front Panel Board to the 
front panel (see Figure 7-9). 




Figure 7-9: Display Module/Front Panel Board Screw Locations 



6. Carefully lift the Display Module/Front Panel Board from the front panel. 



Removing the Front Panel 
Board from the Display 
Module 



1. Remove the four hex nuts (two are shown in Figure 7-10, next page) that hold 
the Display Module to the Front Panel Board. 



2. Disconnect the ribbon cable from the boards. 



3. Carefully separate the Display Module from the Front Panel Board. 



7-12 



1502B MTDR Service Manual 



Maintenance 




Figure 7-10: Display Module/Front Panel Board Showing Hex Nuts 




CAUTION. Do not further disassemble the Display Module. Elastomeric splices are 
used between the circuit boards and they require special alignment fixtures. Parts 
replacement requires special surface-mount technology. 



Changing the Default to The instrument will power up displaying DIST/DIV measurements as meters 
Metric (m/div) or feet (ft/div). Although either measurement mode may be chosen from the 

Setup Menu , the default can easily be changed to cause the preferred mode to come 
up automatically at power up. 



Ribbon Cable Connectors 

Main Board 



J umper 



FrontPanel 
Board 

Figure 7-11 : Location of Default Jumper on Front Panel Board 

1. Remove the instrument from the case. 

2. Remove the bottom EMI shield. 

3. From the bottom side of the instrument, peer into the space between the Main 
Board and the Front Panel Board. The default jumper is located behind the 
screw that holds the Front Panel Assembly to the front-panel mounting stud. 




1502B MTDR Service Manual 



7-13 



Maintenance 



Removing the Option Port 
Assembly 



Troubleshooting 

Troubleshooting Flow 
Chart 



Top of Instrument 



Front 

Panel 

Board 




Metric 




J umper 



Standard 






Bottom of Instrument 



Figure 7-12: Default Jumper Positions 

4. Using a needle-nose plier, slip the jumper off the pins and move it to the desired 
default position (top for meters, bottom for feet). 



1. Remove the Power Supply Module as shown in a previous procedure. 

2. Remove the Front Panel Assembly as previously described. 

3. Remove the ribbon cable on the Main Board that connects the Main Board to 
the Option Port Assembly. 

4. Remove the screw and washer from the instrument side panel. 

5. Remove the nut from the bottom of the instrument. 

6. The Option Port Assembly may be disassembled further by removing the four 
screws from the back of the assembly. This will allow easy access for 
replacement of the Option Port connector. 



When encountering difficulties with the instrument, first use the troubleshooting 
chart in the Operation chapter. This might eliminate any minor problems such as 
fuse or power problems. 

The following troubleshooting flow charts (starting on page 7-17) are designed to 
give you an idea where to start. The Circuit Descriptions and Schematics chapters 
will give further assistance toward solving the problem. 



7-14 



1502B MTDR Service Manual 




Maintenance 



Test Point Waveforms 



The Main Board waveforms represented on the flow chart are representative of an 
instrument in operation per the setup at the top of the flow chart. Additional Main 
Board waveforms are also included in this section. 



The following Main Board waveforms are similar to the waveforms found on the 
troubleshooting flow chart. In some cases, however, the oscilloscope was set to 
show timing rather than the detail of the waveform. For example, TP7010 on the 
flow chart shows the detail of the pulse, but the same test point in the following 
figures shows the repetition rate. 



Set the 1502B front-panel controls: 



CABLE 

NOISE FILTER 
VERT SCALE 
DIST/DIV 
Vp 

Vertical Position 
Horizontal Position 



Attach 3-ft cable 

1 avg (3rd position CW) 

default 

1 ft/div (4th position CW) 

.66 

default 

default 



















1(\onS 




























— 
















1 




r 




I 




r 




r 


























— 




— 




- — 




— 


























\v 








E 











Figure 7-13: Main Board TP1041 






(waveforms continued next page) 



1502B MTDR Service Manual 



7-15 







Maintenance 















100uS 




































1 


1 




i 


1 






















































2 V 




: 


j 










Figure 7-15: Main Board TP6010 Main Board TP7010 




Figure 7-16: Main Board TP9011 Main Board TP9041 




Figure 7-17: Front Panel CABLE Connector 



7-16 



1502B MTDR Service Manual 













1 502B MTDR Service Manual 7-1 7 



Set Front Panel controls: 



CABLE 

NOISE FILTER 
Dl ST/DI V 



Attach 3-ft cable 
1 avg (3rd position CW) 

1 fljOV (4th position CW) 




Maintenance 



Maintenance 





Waveform off top or 
bottom of display or 
wrong height/ 
Waveform flat line? 



No 




Yes 




Good/ Check video TP9041 
on main board 
with scope. 



Good/ Check signal on /Bad 

CABLE with scope /- 

at all pulse widths. / 



Check pulse strobe 
TP9011 on main 
board with scope. 



Good 



Bad 



Bad 



Check sample strobe 
TP7010 on main 
board with scope. 



Bad 



Good 





Check trigger 
TP3040 on main 
board with scope. 



Good 




Check ramp trigger 
TP3041 on main 
board with scope. 



Bad 




7-18 



1502B MTDR Service Manual 





Maintenance 




1502B MTDR Service Manual 



7-19 



Maintenance 



When All Else Fails If it becomes necessary to ship the instrument to an authorized Tektronix Service 

Center, follow the packing instructions as described in Repacking for Shipment on 
page xiv. 



Control Panel Installation 

Watertight Seals To prevent moisture and dirt from getting into the 1502B, special seals are used 
around the LCD faceplate, options port, battery pack port, front panel, and 
front-panel button boot. Removing the front-panel button boot or other rubber seals 
will require special resealing procedures to retain the instrument weathertightness. 

A list of sealants is provided on the next page to aid in reinstallation. However, we 
recommend that resealing be done only by an authorized Tektronix Service Center. 

The front panel/cover seal should be inspected regularly and replaced every six to 
eight months, depending on the operating environment and use. 

All other seals should be inspected during normal adjustment/calibration periods, 
paying special attention to the battery pack port seals, front panel/case seal, and 
option port seal. 



CAUTION. If the case , battery pack, option port, or a front panel control is removed, 
the weathertight integrity of the instrument will be compromised. 



Sealing Materials 



Tek Part No. 


Sealant 


Comments 


006-2302-00 


Dow Corning 3145 Adhesive Sealant 


Use to secure rubber boot around 
buttons, implosion shield to front panel 


252-0199-00 


Dow Corning 3140 Coating 


Use to secure case gaskets to chassis 
(more fluid sealant than 3145 with 
24-hour cure time) 


006-2207-00 


GE G-661 Silicon Grease 


Light coating on case gaskets to pre- 
vent sticking and provide a good seal 


006-0034-00 


Isopropyl alcohol 


Cleaning agent 




If a rubber boot or gasket is replaced: 

1. Remove the old gasket. 

2. Remove all dried adhesive. 

3. Clean area with alcohol and let dry. 



7-20 



1502B MTDR Service Manual 



Maintenance 



4. Run a small bead of 3 140 Coating/Adhesive in the cutout where the new gasket 
will go. 

5. Smooth the adhesive into an even, thin layer. 

6. Clean the new gasket with alcohol and let dry. 

7. Place the gasket on the adhesive and smooth into place. Make sure the edges are 
secure and there are no air bubbles under the gasket. 

8. Let dry for 24 hours before using or reassembling the front panel. 

9. Use silicon grease on the outer side of the front panel gasket and the battery 
gasket where they contact the instrument case. 

The instrument rotary controls, the fuse and line voltage select access covers are 

sealed with rubber O-rings. These are not glued in place, but should be inspected 

and replaced if necessary. 



Top and Bottom EMI Shield Installation 

1. Place the instrument on a solid, non-slip surface with the rear panel facing you. 

2. Hold the EMI shield with the notches in the shield facing the front panel casting. 




Figure 7-18: Installing Top and Bottom EMI Shields 

3. Insert the leading edge of the shield under the lip of the front panel. 



1502B MTDR Service Manual 



7-21 



Maintenance 



4 . Gently push the shield forward inder the lip of the front panel casting as you 
gently press the shield down until its side flanges mate with the grooves in the 
side panels. At this point, the rear flange of the shield should fit over the rear 
panel casting without a gap. 

5 . Secure the shield to the rear casting with three 4-40 screws at five inch-pounds 
of torque. The screw holes in the shield will be offset slightly from those of the 
casting. This assures that the shield will be pulled down tightly when the screws 
are driven in. 

6. Turn instrument over and repeat for the other shield. 

Installing the Case Cover Over the Chassis 

1. Place the instrument chassis face down on a solid, non-slip surface so that the 
rear panel is facing upward. 




2. Reach inside the case and use your fingers to push the four captive mounting 
screws out so that their heads stick up and out of the rear feet. 

3. Align the case with the chassis. 



7-22 



1502B MTDR Service Manual 



Maintenance 



4 . Gently lower the case over the chassis until the front of the case makes contact 
with the groove that surrounds the front panel casting. 

5 . Using a flat-blade screwdriver, secure the four mounting screws (seven 
inch-pounds of torque). Each screw should be started by turning it counterclock- 
wise once, then clockwise. Alternately tighten each screw, gradually, a few turns 
at a time. 

6. Check the gap between the case and the front panel casting to make sure that the 
case and front panel are mated evenly all around. If not mated properly, loosen 
the screws, reposition the case, then tighten the screws again. 



1502B MTDR Service Manual 



7-23 



Maintenance 



7-24 



1502B MTDR Service Manual 



Replaceable Electrical Parts 



Parts Ordering Information 

Replacement parts are available from your Tektronix field office or representative. 





When ordering parts, include the part number plus instrument type, serial number, 
and modification number (if applicable). 

If a part is replaced with a new or improved part, your Tektronix representative will 
contact you regarding any change in part number. 


List of Assemblies 


A list of assemblies is found at the beginning of the replaceable electrical parts list. 
Assemblies are listed in numerical order. When the complete component number 
of a part is known, this list identifies the assembly in which the part is located. 


Mfr. Code 
Number-to-Manufacturer 
Cross Index 


The manufacturer code number-to-manufacturer cross index provides codes, 
names, and addresses of manufacturers of components listed in the replaceable 
electrical parts list. 


Abbreviations 


Abbreviations conform to ANSI standard Y 1 . 1 . 


Component Number 


(Column 1 of electrical parts list) 

A numbering method is used to identify assemblies, subassemblies, and parts. An 
example of this numbering method and typical expansions is as follows: 

A23A2R1234 = A23 A2 R1234 

nL nL nL 

Assembly Subassembly Circuit 

Number Number Number 

Read: resistor 1234 of subassembly 2 of assy 23. 

Only circuit numbers appear on the schematics and circuit board illustrations. Each 
schematic and illustration is marked with its assembly number. Assembly numbers 
are also marked on the mechanical exploded view located in the replaceable 
mechanical parts list. A component number is obtained by adding the assembly 
number prefix to the circuit number. 

This parts list is arranged by assemblies in numerical sequence (e.g., assembly A1 
with its subassemblies and parts precedes A2 with its subassemblies and parts). 

Chassis-mounted parts have no assembly number prefix and are illustrated at the 
end of the replaceable mechanical parts list. 



8-1 

1502B MTDR Service Manual 




Replaceable Electrical Parts 



Tektronix Part No. 


(Column 2) 

This column lists the part number used when ordering a replacement part from 
Tektronix. 


Serial/Model No. 


(Columns 3 and 4) 

Column 3 lists the serial number of the first instrument or the suffix number of the 
circuit board in which the part was used. 

Column 4 lists the serial number of the last instrument or the suffix number of the 
circuit board in which the part was used. No entry indicates that the part is used in 
all instruments. 


Name and Description 


(Column 5) 

In this parts list, the item name is separated from its description by a colon (:). 
Because of space limitations, the item name may appear to be incomplete. For 
further item name identification, refer to the U.S. Federal Cataloging Handbook, 
H6-1. 


Mfg. Code 


(Column 6) 

This column lists the code number of the manufacturer of the part. 


Mfg. Part Number 


(Column 7) 

This column lists the manufacturer’s part number. 



8-2 



1502B MTDR Service Manual 



Replaceable Electrical Parts 



Manufacturers Cross Index 



Mfr. 

Code 


Manufacturer 


Address 


City, State, Zip Code 


01002 


GENERALELECTRICCO 
CAPACITOR PRODUCTS DEPT 


JOHN ST 


HUDSON FALLS NY 12839 


01121 


ALLEN-BRADLEY CO 


1201 S 2ND ST 


MILWAUKEE Wl 53204-2410 


01295 


TEXAS INSTRUMENTS INC 
SEMICONDUCTORGROUP 


13500 N CENTRAL EXPY 
PO BOX 655012 


DALLAS TX 75265 


01686 


RCL ELECTRONICS/SHALLCROSS INC 
SUB OF HIRSCH AND ASSOCIATES INC 


195 MCGREGOR ST 


MANCHESTER NH 03102-3731 


02111 


HAMILTON STANDARD CONTROLS INC 
SPECTROLDIV 


17070 E GALE AVE 
PO BOX 1220 


CITY OF INDUSTRY CA 91749 


03508 


GENERALELECTRICCO 
SEMI-CONDUCTOR PRODUCTS DEPT 


W GENESEE ST 


AUBURN NY 13021 


04222 


AVX CERAMICS 
DIVOF AVXCORP 


19TH AVE SOUTH 
P O BOX 867 


MYRTLE BEACH SC 29577 


04426 


ITW SWITCHES 

DIVOF ILLINOIS TOOL WORKS INC 


6615 W IRVING PARK RD 


CHICAGO IL 60634-2410 


04713 


MOTOROLA INC 

SEMICONDUCTOR PRODUCTS SECTOR 


5005 E MCDOWELL RD 


PHOENIX AZ 85008-4229 


07716 


TRW INC 

TRW IRC FIXED RESISTORS/BURLINGTON 


2850 MT PLEASANT AVE 


BURLINGTON IA 52601 


09922 


BURNDYCORP 


RICHARDS AVE 


NORWALK CT 06852 


0B0A9 


DALLAS SEMICONDUCTOR CORP 


4350 BELTWOODPKWY SOUTH 


DALLAS TX 75244 


0J9R5 


MARCON AMERICACORP 


3 PEARL COURT 


ALLENDALE NJ 07401 


0JR03 


ZMAN MAGNETICS INC 


7633 S 180th 


KENT WA 98032 


0JR04 


TOSHIBA AMERICA INC 
ELECTRONICS COMPONENTS DIV 


2692 DOW AVE 


TUSTIN CA 92680 


10392 


GENERAL STAPLE CO INC 


59-12 37TH ST 


WOODSIDE NY 11377-2523 


12697 


CLAROSTAT MFG CO INC 


LOWER WASHINGTON ST 


DOVER NH 03820 


12954 


MICROSEMI CORP -SCOTTSDALE 


8700 E THOMAS RD 
P O BOX 1390 


SCOTTSDALE AZ 85252 


12969 


UNITRODECORP 


5 FORBES RD 


LEXINGTON MA 02173-7305 


13409 


SENSITRON SEMICONDUCTOR 
DIVOF RSM ELECTRON POWER INC 


221 W INDUSTRY COURT 


DEER PARK NY 11729-4605 


14433 


ITT SEMICONDUCTORS DIV 




WEST PALM BEACH FL 


14552 


MICROSEMI CORP 


2830 S FAIR VIE W ST 


SANTA ANA CA 92704-5948 


14936 


GENERAL INSTRUMENT CORP 
DISCRETE SEMICONDUCTOR DIV 


600 WJOHN ST 


HICKSVILLE NY 11802 



1502B MTDR Service Manual 



8-3 



Replaceable Electrical Parts 



Manufacturers Cross Index (Cont.) 



Mfr. 



Code 


Manufacturer 


Address 


City, State, Zip Code 


16546 


PHILIPS COMPONENTS DISCRETE PRODUCT 
DIV CHIP CAP/CHIP RES FACILITY 


4561 COLORADO BLVD 


LOS ANGELES CA 90039-1103 


17856 


S 1 LIC 0 N IX INC 


2201 LAURELWOOD RD 


SANTA CLARA CA 95054-1516 


18324 


SIGNETICS CORP 
MILITARY PRODUCTS DIV 


4130S MARKETCOURT 


SACRAMENTO CA 95834-1222 


18796 


MURATA ERIE NORTH AMERICAN INC 
STATE COLLEGE OPERATIONS 


1900 W COLLEGE AVE 


STATE COLLEGE PA 16801-2723 


19701 


PHILIPS COMPONENTS DISCRETE PRODUCT 
DIV RESISTIVE PRODUCTS FACILITY 


PO BOX 760 


MINERAL WELLS TX 76067-0760 


1ES66 


MAXIM INTEGRATED PRODUCTS INC 


120 SAN GABRIEL DRIVE 


SUNNYVALE CA 94086 


1W344 


UNITED CHEMI-CON INC 


9801 W HIGGINS SUITE 430 


ROSEMONT IL 60018-4704 


21847 


FEI MICROWAVE INC 


825 STEWART DR 


SUNNYVALE CA 94086-4514 


22526 


DU PONTE IDE NEMOURS ANDCO INC 
DU PONTELECTRONICS DEPT 


515 FISHING CREEK RD 


NEW CUMBERLAND PA 17070-3007 


24165 


SPRAGUE ELECTRIC CO 


267 LOWELL ROAD 


HUDSON NH 03051 


24355 


ANALOG DEVICES INC 


RT1 INDUSTRIAL PK 
PO BOX 9106 


NORWOOD MA 02062 


27014 


NATIONAL SEMICONDUCTOR CORP 


2900 SEMICONDUCTOR DR 


SANTA CLARA CA 95051-0606 


31433 


KEMETELECTRONICS CORP 
NATIONAL SALES HEADQUARTERS 


PO BOX 5928 


GREENVILLE SC 29606 


32997 


BOURNS INC TRIMPOT DIV 


1200 COLUMBIA AVE 


RIVERSIDE CA 92507-2114 


34333 


SILICON GENERAL INC 


11651 MONARCH ST 


GARDEN GROVE CA 92641-1816 


34371 


HARRIS CORP - HARRIS SEMICONDUCTOR 
PRODUCTS GROUP 


200 PALM BAY BLVD 
PO BOX 883 


MELBOURNE FL 32919 


34649 


INTEL CORP SALES OFFICE /ST4- 2/ 


3065 BOWERS AVE 


SANTA CLARA CA 95051 


50434 


HEWLETT-PACKARD CO 
OPTOELECTRONICS DIV 


370 W TRIMBLE RD 


SAN JOSE CA 95131 


53387 


MINNESOTA MINING MFG CO 


PO BOX 2963 


AUSTIN TX 78769-2963 


64537 


KDI ELECTRONICS INC 
SUBSIDIARY OF KDICORP 


31 FARINELLA DR 


EAST HANOVER, NJ 07936 


54937 


DEYOUNG MANUFACTURING INC 


12920 NE 125TH WAY 


KIRKLAND WA 98034-7716 


55680 


NICHICON /AMERICA/CORP 


927 E STATE PKY 


SCHAUMBURG IL 60195-4526 


56637 


RCD COMPONENTS INC 


520 E INDUSTRIAL PARK DR 


MANCHESTER NH 03103 


56845 


DALE ELECTRONICS INC 


2300 RIVERSIDE BLVD 
PO BOX 74 


NORFOLK NE 68701-2242 


56866 


QUALITY THERMISTOR INC 


2096 SOUTH COLE RD SUITE 7 


BOISE ID 83705 



8-4 



1502B MTDR Service Manual 



Replaceable Electrical Parts 



Manufacturers Cross Index (Cont.) 



Mfr. 

Code 


Manufacturer 


Address 


City, State, Zip Code 


57668 


ROHM CORP 


8 WHATNEY PO BOX 19515 


IRVINE CA 92713 


58050 


TEKA PRODUCTS INC 


45 SALEM ST 


PROVIDENCE Rl 02907 


63312 


ENDICOTT RESEARCH GROUP INC 


2601 WAYNE ST PO BOX 269 


ENDICOTT NY 13760-3272 


71590 


CRL COMPONENTS INC 


HWY20W PO BOX 858 


FORT DODGE IA 50501 


75042 


IRC ELECTRONIC COMPONENTS 
PHILADELPHIA DIV 


401 N BROAD ST 


PHILADELPHIA PA 19108-1001 


75378 


CTS KNIGHTS INC 


400 REIMANN AVE 


SANDWICH IL 60548-1846 


75915 


LITTLEFUSE INC, SUB TRACOR INC 


800 E NORTHWEST HWY 


DES PLAINES, IL 60016-3049 


80009 


TEKTRONIX INC 


14150 SW KARL BRAUN DR 
PO BOX 500 


BEAVERTON OR 97077-0001 


81073 


GRAYHILL INC 


561 HILLGROVE AVE 
PO BOX 10373 


LAGRANGE IL 60525-5914 


81855 


EAGLE-PICHER INDUSTRIES INC 
ELECTRONICS DIV 


COUPLES DEPTC AND PORTER STS 
PO BOX 47 


JOPLIN MO 64801 


91637 


DALE ELECTRONICS INC 


2064 12TH AVE 
PO BOX 609 


COLUMBUS NE 68601-3632 



1502B MTDR Service Manual 



8-5 



Replaceable Electrical Parts 



Replaceable Parts List 



Assy 

Number 


Tektronix 
Part Number 


Serial No. 
Effective 


Serial No. 
Discont’d 


Qty Name & Description 


Mfr. 

Code 


Mfr. Part Number 










CIRCUIT BOARD ASSEMBLIES 






A1 


672-1253-00 


R010100 


B021134 


CKT BD ASSY :M AIN , STD INSTR W/EPROM 


80009 


672-1253-00 




672-1253-01 


B021135 


B021151 


CKT BD ASSY :MAIN BD W/EPROM & BATTERY 


80009 


672-1253-01 




672-1253-02 


B021152 


B035824 


CKT BD ASSY :M AIN BD W/EPROM & BATTERY 


80009 


672-1253-02 




672-1253-03 


B035825 


B036453 


CKT BD ASSY :M AIN BD W/EPROM & BATTERY 


80009 


672-1253-03 




672-1253-04 


B036454 


B037359 


CKT BD ASSY :M AIN BD W/EPROM & BATTERY 


80009 


672-1253-04 




672-1253-05 


B037360 




CKT BD ASSY :M AIN BD W/EPROM & BATTERY 


80009 


672-1253-05 










(MOD NB ONLY) 






A1 


672-1312-00 


B025000 


B025368 


CKT BD ASSY :M AIN BD W/EPROM & BATTERY 


80009 


672-1312-00 




672-1312-01 


B025369 


B035824 


CKT BD ASSY :M AIN BD W/EPROM & BATTERY 


80009 


672-1312-01 




672-1312-02 


B035825 


B036694 


CKT BD ASSY :M AIN BD W/EPROM & BATTERY 


80009 


672-1312-02 




672-1312-03 


B036695 


B037359 


CKT BD ASSY :M AIN BD W/EPROM & BATTERY 


80009 


672-1312-03 




672-1312-04 


B037360 




CKT BD ASSY :M AIN BD W/EPROM & BATTERY 


80009 


672-1312-04 


A1A1 


670-9285-00 


R010100 


B020616 


CKT BD ASSYLMAIN W/O EPROM 


80009 


670-9285-00 




670-9285-01 


B020617 


B020797 


CKT BD ASSYLMAIN W/O EPROM 


80009 


670-9285-01 




670-9285-00 


B020798 


B020816 


CKT BD ASSYLMAIN W/O EPROM 


80009 


670-9285-00 




670-9285-01 


B020817 


B021134 


CKT BD ASSYLMAIN W/O EPROM 


80009 


670-9285-01 




670-9285-02 


B021135 


B021151 


CKT BD ASSYLMAIN W/O EPROM 


80009 


670-9285-02 




670-9285-03 


B021152 


B036453 


CKT BD ASSYLMAIN W/O EPROM 


80009 


670-9285-03 




670-9285-04 


B036454 


B037399 


CKT BD ASSYLMAIN W/O EPROM 


80009 


670-9285-04 




670-9285-05 


B037400 




CKT BD ASSYLMAIN W/O EPROM 


80009 


670-9285-05 


A2 


672-1251-00 


R010100 


B020819 


CKT BD ASSY:FRONT PANEL 


80009 


672-1251-00 




672-1251-01 


B020820 


B036453 


CKT BD ASSY:FRONT PANEL 


80009 


672-1251-01 




672-1251-02 


B036454 




CKT BD ASSY:FRONT PANEL 


80009 


672-1251-02 


A3 


620-0477-00 


R010100 


R020398 


POWERSUPPLY ASSEMBLY 


80009 


620-0477-00 




620-0477-01 


R020399 


R024999 


POWERSUPPLY ASSEMBLY 


80009 


620-0477-01 




620-0477-02 


B025000 


B036426 


POWERSUPPLY ASSEMBLY 


80009 


620-0477-02 




620-0477-03 


B036427 




POWERSUPPLY ASSEMBLY 


80009 


620-0477-03 



8-6 



1502B MTDR Service Manual 



Replaceable Electrical Parts 



Replaceable Parts List (Cont.) 



Assy 

Number 


Tektronix 
Part Number 


Serial No. 
Effective 


Serial No. 
Discont’d 


Qty Name & Description 


Mfr. 

Code 


Mfr. Part Number 










CIRCUIT BOARD ASSEMBLIES (Con’t) 






A3A1 


670-9286-00 


R010100 


R010140 


CKT BD ASSY :PO WE R SUPPLY 


80009 


670-9286-00 




670-9286-01 


R010141 


R020398 


CKT BD ASSY :PO WE R SUPPLY 


80009 


670-9286-01 




670-9286-02 


R020399 


B036426 


CKT BD ASSY :PO WE R SUPPLY 


80009 


670-9286-05 




670-9286-03 


B036427 


B036453 


CKT BD ASSY :PO WE R SUPPLY 


80009 


670-9286-03 




670-9286-04 


B036454 


B037399 


CKT BD ASSY :PO WE R SUPPLY 


80009 


670-9286-04 




670-9286-05 


B037400 




CKT BD ASSY :PO WE R SUPPLY 


80009 


670-9286-05 


A4 


670-9291-00 


R010100 


B021134 


CKT BD ASSY:S/R DRIVER SAMPLER 


80009 


670-9291-00 




670-9291-01 


B021135 


B025715 


CKT BD ASSY:S/R DRIVER SAMPLER 


80009 


670-9291-01 




670-9291-02 


B025716 


B036453 


CKT BD ASSY:S/R DRIVER SAMPLER 


80009 


670-9291-02 




670-9291-03 


B036454 


B037399 


CKT BD ASSY:S/R DRIVER SAMPLER 


80009 


670-9291-03 




670-9291-04 


B037400 




CKT BD ASSY:S/R DRIVER SAMPLER 


80009 


670-9291-04 


A5 


672-1241-00 


B010100 


B037542 


CKT BD ASSY :DIS P LAY MODULE 




672-1241-00 




118-9050-00 


B037543 




CKT BD ASSY :DIS P LAY MODULE 




118-9050-00 










(OPTION 03 ONLY) 






A9 


670-6592-00 






CKT BD ASSY :P OWE R FUSE J ACK 


80009 


670-6592-00 



1502B MTDR Service Manual 



8-7 



Replaceable Electrical Parts 



Replaceable Parts List (Cont.) 



Assy 

Number 


Tektronix 
Part Number 


Serial No. 
Effective 


Serial No. 
Discont’d 


Qty Name & Description 


Mfr. 

Code 


Mfr. Part Number 


A1 








CKT BD ASSY:MAIN BD W/EPROM & BATT (Con’t) 














(STANDARD INSTR) 






A1 


672- 1253- XX 






CKT BD ASSY :M AIN W/EPROM & BATTERY 














(MOD NB ONLY) 






A1 


672- 1312- XX 






CKT BD ASSY :M AIN W/EPROM & BATTERY 






A1U2020 


160-4412-02 


R010100 


R010156 


IC,DGTL:EPROM,PRGM 


80009 


160-4412-02 




160-4412-03 


R 010157 


R010184 


IC,DGTL:EPROM,PRGM 


80009 


160-4412-03 




160-4412-06 


R 010185 


R020398 


IC,DGTL:EPROM,PRGM 


80009 


160-4412-06 




160-4412-07 


R020399 


B021134 


IC,DGTL:EPROM,PRGM 


80009 


160-4412-07 




160-4412-08 


B021135 


B035824 


IC,DGTL:EPROM,PRGM 


80009 


160-4412-08 




160-4412-09 


B035825 




IC,DGTL:EPROM,PRGM 


80009 


160-4412-09 


A1BT1010 


146-0049-00 


B021135 




BATTERY, STO R AG E :3.5V f 750M AH SFTY CONT 


81855 


LTC-7P 


A1BT1010 


146-0079-00 


B025000 




BATTERY:SILVER OXIDE 3.0V 


80009 


146-0079-00 










(MOD NB ONLY) 






A1A1 


670-9285-XX 






CIRCUIT BD ASSY:MAIN W/O EPROM 






A1A1BT1010 


146-0049-00 


R010100 


B021134 


BATTERY, STORAGE:3.5V,750MAH SFTY CONT 


81855 


LTC-7P 


A1A1C 1010 


281-0925-01 






CAP ,F XD,C E R DI:MLC,0.22UF,20%,50V,Z5U 


31433 


C114C224M5Y5CA 


A1A1C 1011 


281-0925-01 






CAP ,F XD,C E R DI:MLC,0.22UF,20%,50V,Z5U 


31433 


C114C224M5Y5CA 


A1A1C 1020 


281-0925-01 






CAP ,F XD,C E R DI:MLC,0.22UF,20%,50V,Z5U 


31433 


C114C224M5Y5CA 


A1A1C 1021 


281-0925-01 






CAP ,F XD,C E R DI:MLC,0.22UF,20%,50V,Z5U 


31433 


C114C224M5Y5CA 


A1A1C 1022 


283-0359-01 






CAP ,F XD,C E R Dl :1000P F ,5%,200V SQ 


31433 


C322C102J 2G5CA 


A1A1C 1023 


283-0359-01 






CAP ,F XD,C E R Dl :1000P F ,5%,200V SQ 


31433 


C322C102J 2G5CA 


A1A1C 1024 


283-0359-01 






CAP ,F XD,C E R Dl :1000P F ,5%,200V SQ 


31433 


C322C102J 2G5CA 


A1A1C 1030 


283-0190-00 






CAP ,F XD,C E R Dl :0.47U F ,5%,50V SQ 


04222 


SR305C474J AA 


A1A1C 1031 


281-0925-01 






CAP ,F XD,C E R DI:MLC,0.22UF,20%,50V,Z5U 


31433 


C114C224M5Y5CA 


A1A1C 1032 


283-0359-01 






CAP ,F XD,C E R Dl :1000P F ,5%,200V SQ 


31433 


C322C102J 2G5CA 



8-8 1 502B MTDR Service Manual 



Replaceable Electrical Parts 



Replaceable Parts List (Cont.) 



Assy 

Number 


Tektronix 
Part Number 


Serial No. 
Effective 


Serial No. 
Discont’d 


Qty Name & Description 


Mfr. 

Code 


Mfr. Part Number 


A1A1 


670-9285-XX 






CIRCUIT BD ASSY:MAIN W/O EPROM (Con’t) 






A1A1C1040 


281-0925-01 






CAP f FXD f C E R DI:MLC ,0.2211 F f 20% l 50V f Z5U 


31433 


C114C224M5Y5CA 


A1A1C 1041 


281-0925-01 






CAP f FXD f C E R DI:MLC ,0.2211 F f 20% l 50V f Z5U 


31433 


C114C224M5Y5CA 


A1A1C 1042 


290-1087-00 






CAP,FXD,ELCTLT:100UF, 25V, AXIAL 


1W344 


KM C 25T101M 8X11LL 


A1A1C 1043 


281-0925-01 






CAP,FXD,CER DI:MLC ,0.2211 F f 20% l 50V f Z5U 


31433 


C114C224M5Y5CA 


A1A1C 2010 


281-0925-01 






CAP ,FXD,C E R DI:MLC ,0.2211 F f 20% l 50V,Z5U 


31433 


C114C224M5Y5CA 


A1A1C 2011 


290-0748-00 






CAP,FXD ; ELCTLT:10UF, +50-20%, 25WVDC 


0J9R5 


C E U SHE 100 


A1A1C 2012 


281-0925-01 






C AP ,FXD,C E R DI:MLC l 0.22UF,20% l 50V f Z5U 


31433 


C114C224M5Y5CA 


A1A1C 2013 


281-0925-01 






C AP ,FXD,C E R DI:MLC I 0.22UF I 20% I 50V,Z5U 


31433 


C114C224M5Y5CA 


A1A1C 2014 


281-0925-01 






C AP ,FXD,C E R DI:MLC I 0.22UF I 20% I 50V,Z5U 


31433 


C114C224M5Y5CA 


A1A1C 2015 


283-0111-04 






C AP ,FXD,C E R Dl :0.1U F ,20%,50V SQ 


04222 


SR595C104MAAAP1 


A1A1C 2016 


283-0238-00 






C AP ,FXD,C E R Dl :0.01U F ,10%,50V SQ 


04222 


SR155C103KAA 


A1A1C 2020 


281-0925-01 






C AP ,FXD,C E R DI:MLC I 0.22UF l 20% l 50V,Z5U 


31433 


C114C224M5Y5CA 


A1A1C 2021 


281-0925-01 






C AP ,FXD,C E R DI:MLC I 0.22UF l 20% l 50V,Z5U 


31433 


C114C224M5Y5CA 


A1A1C 2030 


281-0925-01 






C AP ,FXD,C E R DI:MLC I 0.22UF ,20% l 50V f Z5U 


31433 


C114C224M5Y5CA 


A1A1C 2031 


281-0925-01 






C AP ,FXD,C E R DI:MLC I 0.22UF ,20% l 50V f Z5U 


31433 


C114C224M5Y5CA 


A1A1C 2032 


281-0925-01 






C AP ,FXD,C E R DI:MLC I 0.22UF I 20% I 50V,Z5U 


31433 


C114C224M5Y5CA 


A1A1C 2033 


281-0925-01 






C AP ,FXD,C E R DI:MLC I 0.22UF ,20% I 50V I Z5U 


31433 


C114C224M5Y5CA 


A1A1C 2034 


281-0925-01 






C AP ,FXD,C E R DI:MLC I 0.22UF ,20% l 50V f Z5U 


31433 


C114C224M5Y5CA 


A1A1C 2035 


281-0925-01 






CAP ,FXD,C E R D l:MLC ,0.2211 F f 20% l 50V,Z5U 


31433 


C114C224M5Y5CA 


A1A1C 2036 


281-0925-01 






CAP ,FXD f C E R D l:MLC ,0.2211 F f 20% l 50V,Z5U 


31433 


C114C224M5Y5CA 


A1A1C 2037 


281-0925-01 






CAP ,FXD f C E R DI:MLC ,0.2211 F f 20% l 50V,Z5U 


31433 


C114C224M5Y5CA 


A1A1C 2038 


281-0925-01 






CAP ,FXD,C E R DI:MLC ,0.2211 F f 20% l 50V,Z5U 


31433 


C114C224M5Y5CA 


A1A1C 2039 


283-0067-00 


B021135 




CAP, FXD.CER DI:0.001UF,10% f 200V 


18796 


DD09B10 Y5F 102K 200V 


A1A1C 2040 


283-0059-02 






CAP ,FXD,C E R DI:1UF,20%,50V 


04222 


S R 305C 105MAATRSTDII 


A1A1C 2041 


283-0059-02 






CAP ,FXD,C E R DI:1UF,20%,50V 


04222 


S R 305C 105MAATRSTDII 


A1A1C 2042 


281-0925-01 






CAP ,FXD,C E R DI:MLC ,0.2211 F f 20% l 50V,Z5U 


31433 


C114C224M5Y5CA 


A1A1C 2043 


283-0238-00 






CAP ,FXD,C E R Dl :0.01U F ,10%,50V SQ 


04222 


SR155C103KAA 


A1A1C 2044 


281-0925-01 






CAP ,FXD,C E R DI:MLC,0.22UF,20%,50V,Z5U 


31433 


C114C224M5Y5CA 


A1A1C 2045 


283-0421-00 






CAP,FXD,CER DhO.lUF, +80-20%, 50V 


24165 


923CX7R104M050B 


A1A1C 2046 


283-0067-00 


B021135 




CAP ,FXD,C E R DI:0.001UF,10%,200V 


18796 


DD09B10 Y5F 102K 200V 


A1A1C 3020 


281-0925-01 






CAP ,FXD,C E R DI:MLC,0.22UF,20%,50V,Z5U 


31433 


C114C224M5Y5CA 


A1A1C 3021 


281-0925-01 






CAP ,FXD,C E R DI:MLC,0.22UF,20%,50V,Z5U 


31433 


C114C224M5Y5CA 



1502B MTDR Service Manual 



8-9 



Replaceable Electrical Parts 



Replaceable Parts List (Cont.) 


Assy 


Tektronix 


Serial No. 


Serial No. 




Mfr. 




Number 


Part Number 


Effective 


Discont’d 


Qty Name & Description 


Code 


Mfr. Part Number 


A1A1 


670-9285-XX 






CIRCUIT BD ASSY:MAIN W/O EPROM (Con’t) 






A1A1C 3022 


281-0925-01 






CAP f FXD f C E R DI:MLC ,0.2211 F,20% l 50V f Z5U 


31433 


C114C224M5Y5CA 


A1A1C 3023 


281-0925-01 






CAP ,FXD f C E R DI:MLC ,0.2211 F,20% l 50V f Z5U 


31433 


C114C224M5Y5CA 


A1A1C3030 


283-0181-00 






CAP ,FXD,C E R Dl :1.8P F ,+/- 0.1%,100V SQ 


24165 


5024E0200RD221K 


A1A1C 3040 


283-0107-00 






CAP ,FXD,C E R DI:51P F ,5% I 200V SQ 


04222 


SR202A510J AA 


A1A1C 3041 


283-0167-00 






CAP ,FXD,C E R Dl :0.1U F , 10%, 100V SQ 


04222 


SR211C104KAA 


A1A1C 3042 


283-0108-00 






C AP ,FXD,C E R Dl :220P F ,10% f 200V SQ 


04222 


SR152A221KAA 


A1A1C 3043 


283-0330-00 






C AP ,FXD,C E R D 1 :100P F ,5% I 50V SQ 


16546 


CN15C101J 


A1A1C 3044 


283-0359-01 






C AP ,FXD,C E R Dl :1000P F ,5% I 200V SQ 


31433 


C322C102J 2G5CA 


A1A1C 3045 


281-0925-01 






C AP ,FXD,C E R DI:MLC I 0.22UF l 20% l 50V,Z5U 


31433 


C114C224M5Y5CA 


A1A1C 3046 


281-0925-01 






C AP ,FXD,C E R DI:MLC I 0.22UF l 20% l 50V,Z5U 


31433 


C114C224M5Y5CA 


A1A1C3047 


283-0181-00 






C AP ,FXD,C E R Dl :1.8P F ,+/- 0.1%,100V SQ 


24165 


5024E0200RD221K 


A1A1C 3048 


283-0359-01 






C AP ,FXD,C E R Dl :1000P F ,5% I 200V SQ 


31433 


C322C102J 2G5CA 


A1A1C4020 


281-0925-01 






CAP,FXD,CERDI:MLC,0.22UF,20%,50V,Z5U 


31433 


C114C224M5Y5CA 


A1A1C4021 


283-0359-01 






C AP ,FXD,C E R Dl :1000P F ,5% I 200V SQ 


31433 


C322C102J 2G5CA 


A1A1C4022 


285-1241-00 






CAP,FXD,PLASTIC :0.22U F ,10%,100V 


12954 


B32571. 22/10/100 


A1A1C4030 


281-0925-01 






C AP ,FXD,C E R DI:MLC I 0.22UF ,20% l 50V f Z5U 


31433 


C114C224M5Y5CA 


A1A1C4040 


281-0813-00 






C AP ,FXD,C E R DI:M LC ,0.0411 F ,20%,50V 


04222 


SA105E473MAA 


A1A1C4041 


290-0748-00 






CAP,FXD ; ELCTLT:10UF, +50-20%, 25WVDC 


0J9R5 


C E U SHE 100 


A1A1C 5010 


283-0330-00 






CAP ,FXD,C E R DhlOOP F,5% I 50V SQ 


16546 


CN15C101J 


A1A1C 5020 


283-0359-01 






CAP ,FXD,C E R Dl :1000P F ,5% I 200V SQ 


31433 


C322C102J 2G5CA 


A1A1C 5021 


283-0359-01 






CAP ,FXD,C E R Dl :1000P F ,5% I 200V SQ 


31433 


C322C102J 2G5CA 


A1A1C 5022 


281-0925-01 






CAP ,FXD f C E R DI:MLC ,0.2211 F,20% l 50V f Z5U 


31433 


C114C224M5Y5CA 


A1A1C 5023 


283-0359-01 






CAP ,FXD,C E R Dl :1000P F ,5% I 200V SQ 


31433 


C322C102J 2G5CA 


A1A1C 5024 


283-0177-00 






CAP ,FXD f C E R DI:1U F ,+80- 20%,25V 


04222 


SR305E105ZAA 


A1A1C 5025 


283-0177-00 






CAP ,FXD f C E R DI:1U F ,+80- 20%,25V 


04222 


SR305E105ZAA 


A1A1C 5030 


281-0813-00 






CAP ,FXD f C E R DI:M LC ,0.0411 F ,20%,50V 


04222 


SA105E473MAA 


A1A1C 5031 


281-0813-00 






CAP ,FXD f C E R DI:M LC ,0.0411 F ,20%,50V 


04222 


SA105E473MAA 


A1A1C 5032 


281-0798-00 






CAP ,FXD,C E R DI:51PF f l% f 100V TUBULAR, Ml 


04222 


SA101A510GAA 


A1A1C 5033 


283-0330-00 






CAP ,FXD,C E R DhlOOP F,5% I 50V SQ 


16546 


CN15C101J 


A1A1C 5040 


283-0330-00 






CAP ,FXD,C E R DhlOOP F,5% I 50V SQ 


16546 


CN15C101J 


A1A1C 5041 


281-0925-01 






CAP ,FXD f C E R DI:MLC f 0.22UF f 20% l 50V f Z5U 


31433 


C114C224M5Y5CA 


A1A1C 5042 


281-0925-01 






CAP ,FXD f C E R DI:MLC f 0.22UF f 20% l 50V f Z5U 


31433 


C114C224M5Y5CA 



8-10 



1502B MTDR Service Manual 



Replaceable Electrical Parts 



Replaceable Parts List (Cont.) 



Assy 

Number 


Tektronix 
Part Number 


Serial No. 
Effective 


Serial No. 
Discont’d 


Qty Name & Description 


Mfr. 

Code 


Mfr. Part Number 


A1A1 


670-9285-XX 






CIRCUIT BD ASSY:MAIN W/O EPROM (Con’t) 






A1A1C6030 


281-0925-01 






CAP f FXD f C E R DI:MLC ,0.2211 F f 20% l 50V f Z5U 


31433 


C114C224M5Y5CA 


A1A1C 6031 


283-0177-00 






CAP f FXD f C E R DI:1U F ,+80- 20%,25V 


04222 


SR305E105ZAA 


A1A1C 6032 


281-0925-01 






CAP f FXD,C E R DI:MLC ,0.2211 F f 20% l 50V f Z5U 


31433 


C114C224M5Y5CA 


A1A1C 7010 


283-0111-04 






CAP ,FXD,C E R Dl :0.1U F ,20% f 50V SQ 


04222 


SR595C104MAAAP1 


A1A1C 7020 


281-0813-00 






CAP ,FXD f C E R DI:M LC ,0.0411 F ,20%,50V 


04222 


SA105E473MAA 


A1A1C 7021 


281-0925-01 






C AP ,FXD,C E R DI:MLC I 0.22UF l 20% l 50V,Z5U 


31433 


C114C224M5Y5CA 


A1A1C 7022 


283-0359-01 






C AP ,FXD,C E R Dl :1000P F ,5% I 200V SQ 


31433 


C322C102J 2G5CA 


A1A1C 7023 


283-0177-00 






CAP, FXD,CERDI:1UF, +80-20%, 25V 


04222 


SR305E105ZAA 


A1A1C 7030 


283-0059-02 






CAP,FXD,CER DI:1UF,20%,50V 


04222 


S R305C 105M AATRSTDII 


A1A1C 7040 


283-0330-00 






CAP,FXD,CER DI:100PF,5%,50V SQ 


16546 


CN15C101J 


A1A1C 7041 


281-0925-01 






CAP,FXD,CERDI:MLC,0.22UF,20%,50V,Z5U 


31433 


C114C224M5Y5CA 


A1A1C 7042 


281-0925-01 






CAP,FXD,CERDI:MLC,0.22UF,20%,50V,Z5U 


31433 


C114C224M5Y5CA 


A1A1C 7043 


290-0748-00 






CAP, FXD,ELCTLT:10UF, +50-20%, 25WVDC 


0J9R5 


C E U SHE 100 


A1A1C 8010 


281-0925-01 






CAP,FXD,CERDI:MLC,0.22UF,20%,50V,Z5U 


31433 


C114C224M5Y5CA 


A1A1C 8020 


283-0010-00 






C AP ,FXD,C E R DI:0.05UF, +80-20%, 50V SQ 


04222 


SR305E503ZAA 


A1A1C 8021 


281-0798-00 






C AP ,FXD,C E R DI:51PF,1%,100V TUBULAR, Ml 


04222 


SA101A510GAA 


A1A1C 8022 


283-0330-00 






C AP ,FXD,C E R D 1 :100P F ,5%,50V SQ 


16546 


CN15C101J 


A1A1C 8023 


281-0925-01 






CAP,FXD,CERDI:MLC,0.22UF,20%,50V,Z5U 


31433 


C114C224M5Y5CA 


A1A1C 8024 


283-0348-00 






CAP ,FXD,C E R DI:0.5P F ,+/- 0.1P F ,100V 


31433 


C312C109D1G5EA 


A1A1C 8040 


283-0156-00 






CAP ,FXD,C E R DL1000PF, +80-20%, 200V SQ 


04222 


SR152E102ZAA 


A1A1C9010 


283-0111-04 






CAP ,FXD,C E R Dl :0.1U F ,20%,50V SQ 


04222 


SR595C104MAAAP1 


A1A1C 9011 


281-0813-00 






CAP ,FXD,C E R DI:MLC,0.047UF,20%,50V 


04222 


SA105E473MAA 


A1A1C 9020 


283-0359-01 






CAP ,FXD,C E R Dl :1000P F ,5%,200V SQ 


31433 


C322C102J 2G5CA 


A1A1C 9021 


281-0925-01 






CAP ,FXD,C E R DI:MLC,0.22UF,20%,50V,Z5U 


31433 


C114C224M5Y5CA 


A1A1C 9022 


281-0813-00 






CAP ,FXD,C E R DI:MLC,0.04UF,20%,50V 


04222 


SA105E473MAA 


A1A1C 9023 


281-0925-01 






CAP ,FXD,C E R DI:MLC,0.22UF,20%,50V,Z5U 


31433 


C114C224M5Y5CA 


A1A1C 9024 


281-0813-00 






CAP ,FXD,C E R DI:MLC,0.04UF,20%,50V 


04222 


SA105E473MAA 


A1A1C 9025 


281-0925-01 






CAP ,FXD,C E R DI:MLC,0.22UF,20%,50V,Z5U 


31433 


C114C224M5Y5CA 


A1A1C 9030 


281-0925-01 






CAP ,FXD,C E R DI:MLC,0.22UF,20%,50V,Z5U 


31433 


C114C224M5Y5CA 


A1A1C 9031 


290-0748-00 






CAP, FXD,ELCTLT:10UF, +50-20%, 25WVDC 


0J9R5 


C E U SHE 100 


A1A1C 9032 


283-0359-01 






CAP ,FXD,C E R Dl :1000P F ,5%,200V SQ 


31433 


C322C102J 2G5CA 


A1A1C 9033 


283-0359-01 






CAP ,FXD,C E R Dl :1000P F ,5%,200V SQ 


31433 


C322C102J 2G5CA 



1502B MTDR Service Manual 



8-11 



Replaceable Electrical Parts 



Replaceable Parts List (Cont.) 



Assy 

Number 


Tektronix 
Part Number 


Serial No. 
Effective 


Serial No. 
Discont’d 


Qty Name & Description 


Mfr. 

Code 


Mfr. Part Number 


A1A1 


670-9285-XX 






CIRCUIT BD ASSY:MAIN W/O EPROM (Con’t) 






A1A1C 9034 


281-0925-01 






CAP f FXD f C E R DI:MLC ,0.2211 F f 20% l 50V f Z5U 


31433 


C114C224M5Y5CA 


A1A1C 9035 


290-0748-00 






CAP, FXD,ELCTLT:10UF, +50-20%, 25W VDC 


0J9R5 


CEUST1E100 


A1A1CR1020 


152-0322-00 






DIODE DVC,DI:SC HOTTKY.S l,15V,1.2P F 


21847 


A2X600 


A1A1C R 1021 


152-0322-00 






DIODE DVC,DI:SC HOTTKY.S l,15V,1.2P F 


21847 


A2X600 


A1A1C R 1022 


152-0322-00 






DIODE DVC,DI:SCHOTTKY,SI,15V,1.2PF 


21847 


A2X600 


A1A1C R 1023 


152-0322-00 






DIODE DVC,DI:SCHOTTKY,SI,15V,1.2PF 


21847 


A2X600 


A1A1C R 3031 


152-0322-00 






DIODE DVC,DI:SCHOTTKY,SI,15V,1.2PF 


21847 


A2X600 


A1A1CR4030 


152-0141-02 






DIODE,SIG:ULTRA FAST ;40V,150M A,4N S ,2P F 


01295 


1N4152R 


A1A1CR4031 


152-0322-00 






DIODE DVC,DI:SCHOTTKY,SI,15V,1.2PF 


21847 


A2X600 


A1A1CR4032 


152-0725-00 






DIODE DVC,DI:SI,SCHOTTKY,20V,1.2PF 


21847 


A2X1582 


A1A1C R 5030 


152-0725-00 






DIODE DVC,DI:S l,S C HOTTKY ,20V,1.2P F 


21847 


A2X1582 


A1A1C R 5040 


152-0322-00 






DIODE DVC,DI:SCHOTTKY,SI,15V,1.2PF 


21847 


A2X600 


A1A1C R 8020 


152-0322-00 






DIODE DVC,DI:SCHOTTKY,SI,15V,1.2PF 


21847 


A2X600 


A1A1CR9010 


152-0322-00 






DIODE DVC,DI:SCHOTTKY,SI,15V,1.2PF 


21847 


A2X600 


A1A1J 2010 


131-3361-00 






CONN,HDR:PCB,MALE,RTANG,2 X 13,0.1 CTR 


53387 


3593-5002 


A1A1J 5040 


131-4183-00 






CONN,HDR:PCB,MALE,STR,2 X 7,0.1 CTR 


53387 


3598-6002 


A1A1J 9010 


131-3359-00 






CONN,HDR:PCB,MALE,RTANG,2X 10,0.1 CTR 


53387 


3592-5002 


A1A1L5030 


120-1606-00 






XFMR,RF:INDUCTOR 86-10 


0JR03 


120-1606-00 


A1A1L5040 


108-0509-01 


B021135 




COIL,RF:FIXED,2.45UH +/-10%, AXIAL LEAD 


0JR03 


108-0509-01 


A1A1M 1030 


149-0057-00 


R010100 


R020511 


METER, ET:MINITURE,620-PC 


80009 


149-0057-00 


A1A1Q1010 


151-1176-00 






XSTR,PWR:MOS,P-C H ;100V,1.0A,0.6 OHM 


04713 


IRFD9120 


A1A1Q1020 


151-0190-00 






XSTR,SIG:BIPOLAR,NPN;40V,200MA,300MHZ,AMP 


01295 


SKA3703 


A1A1Q1021 


151-0188-00 






XSTR,SIG:BIPOLAR,PNP;40V,200MA,250MHZ,AMP 


03508 


X39H3162 


A1A1Q1030 


151-0190-00 






XSTR,SIG:BIPOLAR,NPN;40V,200MA,300MHZ,AMP 


01295 


SKA3703 


A1A1Q1031 


151-0188-00 






XSTR,SIG:BIPOLAR,PNP;40V,200MA,250MHZ,AMP 


03508 


X39H3162 


A1A1Q2011 


151-1176-00 






XSTR,PWR:MOS,P-CH;100V,1.0A,0.6 0HM 


04713 


IRFD9120 


A1A1Q2012 


151-1176-00 






XSTR,PWR:MOS,P-C H ;100V, 1.0A.0.6 OHM 


04713 


IRFD9120 



8-12 



1502B MTDR Service Manual 



Replaceable Electrical Parts 



Replaceable Parts List (Cont.) 


Assy 

Number 


Tektronix 
Part Number 


Serial No. 
Effective 


Serial No. 
Discont’d 


Qty Name & Description 


Mfr. 

Code 


Mfr. Part Number 


A1A1 


670-9285-XX 






CIRCUIT BD ASSY:MAIN W/O EPROM (Con’t) 






A1A1Q3030 


151-0276-01 






XSTR,SIG :BIPOLAR,PNP ;50V,50M A,40M HZ,AM P 


04713 


2N5087RLRP 


A1A1Q4030 


151-1078-00 






XSTR ,S IG :J F ET,N - C H ;3.5V,75M A,90 OHM;TO-92 


04713 


SPF3040 


A1A1Q4031 


151-0441-00 






XSTR, SIG:BIPOLAR,NPN;15V,40MA,1.0GHZ, AMP 


04713 


2N3839 


A1A1Q4040 


151-0271-00 






XSTR,SIG:BIPOLAR,PNP ;15V,30M A f 2.0G HZ,AM P 


01295 


SKA4504 


A1A1Q5020 


151-0353-00 


R010100 


R020409 


XSTR :NPN, SI, DUAL 


80009 


151-0353-00 




151-0232-00 


R020410 


B021151 


XSTR, SIG:BIPOLAR,NPN, 45V, 30MA,60MHZ, AMP 


80009 


151-0232-00 




151-0308-00 


B021152 




XSTR, SIG:BIPOLAR,NPN;45V,30MA,60MHZ, AMP 


04713 


2N2918 


A1A1Q5030 


151-0441-00 






XSTR, SIG:BIPOLAR,NPN;15V,40MA,1.0GHZ, AMP 


04713 


2N3839 


A1A1Q5031 


151-1012-00 






ZSTR ,S IG :J FET,N-CH,6V,15MA,4.5MS,AMP 


21845 


F1585 


A1A1Q5032 


151-0354-00 


R010100 


B021151 


XSTR:PNP,SI,DUA 


80009 


151-0354-00 




151-0261-00 


B021152 




XSTR, SIG:BIPOLAR,PNP;60V,50MA,100MHZ, AMP 


04713 


2N3810 


A1A1Q6020 


151-0271-00 






XSTR, SIG:BIPOLAR,PNP;15V,30MA,2.0GHZ, AMP 


01295 


SKA4504 


A1A1Q7020 


151-0441-00 






XSTR, SIG:BIPOLAR,NPN;15V,40MA,1.0GHZ, AMP 


04713 


2N3839 


A1A1Q7021 


151-0139-00 






XSTR, SIG:BIPOLAR,NPN;15V,50MA,600MHZ, AMP 


04713 


MD918 


A1A1Q7030 


151-0441-00 






XSTR, SIG:BIPOLAR,NPN;15V,40MA,1.0GHZ, AMP 


04713 


2N3839 


A1A1Q8020 


151-0139-00 






XSTR, SIG:BIPOLAR,NPN;15V,50MA,600MHZ, AMP 


04713 


MD918 


A1A1Q9010 


151-0271-00 






XSTR, SIG:BIPOLAR,PNP;15V,30MA,2.0GHZ, AMP 


01295 


SKA4504 


A1A1Q9020 


151-0353-00 


R010100 


R020409 


XSTR:NPN,SI,DUAL 


80009 


151-0353-00 




151-0232-00 


R020410 


B021151 


XSTR, SIG:BIPOLAR,NPN, 45V, 30MA,60MHZ, AMP 


80009 


151-0232-00 




151-0308-00 


B021152 




XSTR, SIG:BIPOLAR,NPN;45V,30MA,60MHZ, AMP 


04713 


2N2918 


A1A1Q9021 


151-0271-00 






XSTR, SIG:BIPOLAR,PNP;15V,30MA,2.0GHZ, AMP 


01295 


SKA4504 


A1A1R1010 


322-3162-00 






RE S,FXD:M ETAL FILM:475 OHM,1%,0.2W 


57668 


CRB20FXE 475E 


A1A1R1011 


322-3289-00 






RE S,FXD:M ETAL FILM:10.0K OHM,1%,0.2W 


57668 


CRB20FXE 10K0 


A1A1R 1012 


322-3289-00 






RE S,FXD:M ETAL FILM:10.0K OHM,1%,0.2W 


57668 


CRB20FXE 10K0 


A1A1R 1013 


322-3289-00 






RE S,FXD:M ETAL FILM:10.0K OHM,1%,0.2W 


57668 


CRB20FXE 10K0 


A1A1R 1014 


322-3385-00 






RE S,FXD:M ETAL FILM:100K OHM,1%,0.2W 


57668 


CRB20FXE 100K 


A1A1R 1015 


322-3318-00 






RE S,FXD:M ETAL FILM:20.0K OHM,1%,0.2W 


57668 


CRB20FXE 20K0 


A1A1R 1016 


322-3097-00 






RE S,FXD:M ETAL FILM:100 OHM ,1%,0.2W 


57668 


CRB20FXE 100E 


A1A1R 1020 


322-3289-00 






RE S,FXD:M ETAL FILM:10.0K OHM,1%,0.2W 


57668 


CRB20FXE 10K0 


A1A1R 1021 


322-3289-00 






RE S,FXD:M ETAL FILM:10.0K OHM,1%,0.2W 


57668 


CRB20FXE 10K0 


A1A1R 1022 


322-3289-00 






RE S,FXD:M ETAL FILM:10.0K OHM,1%,0.2W 


57668 


CRB20FXE 10K0 


A1A1R 1023 


322-3289-00 






RES,FXD:M ETAL FILM:10.0K OHM,1%,0.2W 


57668 


CRB20FXE 10K0 



1502B MTDR Service Manual 



8-13 



Replaceable Electrical Parts 



Replaceable Parts List (Cont.) 



Assy 

Number 


Tektronix 
Part Number 


Serial No. 
Effective 


Serial No. 
Discont’d 


Qty Name & Description 


Mfr. 

Code 


Mfr. Part Number 


A1A1 


670-9285-XX 






CIRCUIT BD ASSY:MAIN W/O EPROM (Con’t) 






A1A1R1030 


321-0523-00 


R010100 


R020511 


RES,FXD,FILM:2.74M OHM ,1%,0.125W 


80009 


321-0523-00 


A1A1R 1031 


321-0523-00 


R010100 


R020511 


RES,FXD,FILM:2.74M OHM ,1%,0.125W 


80009 


321-0523-00 


A1A1R 1032 


322-3437-00 






RES,FXD ( FILM:348K OHM,1%,0.2W 


57668 


CRB20FXE 348K 


A1A1R 1033 


307-0446-00 






RES NTWK,FXD,FI:10K OHM,20%,(9)RES 


01121 


210A103 


A1A1R 1035 


321-0756-00 






RES,FXD,FILM:50K OHM ,1%,0.125W 


01121 


ADVISE 


A1A1R2010 


322-3097-00 






RES,FXD:M ETAL FILM:100 OHM,1%,0.2W 


57668 


CRB20FXE 100E 


A1A1R2011 


322-3318-00 






RES,FXD:M ETAL FILM:20.0K OHM,1%,0.2W 


57668 


CRB20FXE 20K0 


A1A1R2012 


322-3385-00 






RES,FXD:M ETAL FILM:100K OHM,1%,0.2W 


57668 


CRB20FXE 100K 


A1A1R2013 


322-3385-00 






RES,FXD:M ETAL FILM:100K OHM,1%,0.2W 


57668 


CRB20FXE 100K 


A1A1R2014 


307-0446-00 






RES NTWK,FXD,FI:10K OHM,20%,(9)RES 


01121 


210A103 


A1A1R2015 


307-0446-00 






RES l\ITWK,FXD,FI:10K OHM,20%,(9)RES 


01121 


210A103 


A1A1R2030 


322-3239-00 






RES,FXD,FILM:3.01K OHM,1%,0.2W 


57668 


CRB20FXE 3K01 


A1A1R2031 


322-3239-00 






RES,FXD,FILM:3.01K OHM,1%,0.2W 


57668 


CRB20FXE 3K01 


A1A1R2033 


322-3293-00 






RES,FXD:M ETAL FILM:11.0K OHM,1%,0.2W 


57668 


CRB20FXE 11K0 


A1A1R2034 


311-0634-00 






RES,VAR,NONWW:TRMR,500 OHM,0.5W CERMET 


32997 


3329H-L58-501 


A1A1R2040 


322-3139-00 






RES,FXD:M ETAL FILM:274 OHM,1%,0.2W 


57668 


CRB20FXE 274E 


A1A1R2041 


322-3134-00 






RES,FXD,FILM:243 OHM ,1%,0.2W 


57668 


CRB20 FXE243E 


A1A1R2042 


322-3134-00 






RES,FXD,FILM:243 OHM ,1%,0.2W 


57668 


CRB20 FXE243E 


A1A1R2043 


322-3126-00 






RES,FXD,FILM:200 OHM ,1%,0.2W 


91637 


CCF501G200R0F 


A1A1R 3010 


322-3097-00 






RE S,FXD:M ETAL FILM:100 OHM ,1%,0.2W 


57668 


CRB20FXE 100E 


A1A1R3020 


322-3297-00 






RE S,FXD:M ETAL FILM:12.1K OHM,1%,0.2W 


57668 


CRB20FXE 12K1 


A1A1R 3030 


322-3097-00 






RE S,FXD:M ETAL FILM:100 OHM ,1%,0.2W 


57668 


CRB20FXE 100E 


A1A1R 3031 


322-3356-00 






RES,FXD,FILM:49.9K OHM,1%,0.2W 


57668 


CRB20FXE 49K9 


A1A1R 3032 


322-3327-00 






RES,FXD,FILM:24.9K OHM,1%,0.2W 


57668 


CRB20FXE 24K9 


A1A1R 3033 


322-3165-00 






RES,FXD,FILM:511 OHM ,1%,0.2W 


57668 


CRB20FXE 511E 


A1A1R 3034 


322-3261-00 






RES,FXD,FILM:5.11K OHM,1%,0.2W 


91637 


CCF50G5111FT 


A1A1R 3035 


322-3289-00 






RE S,FXD:M ETAL FILM:10.0K OHM,1%,0.2W 


57668 


CRB20FXE 10K0 


A1A1R 3036 


322-3243-00 






RE S,FXD:M ETAL FILM:3.32K OHM,1%,0.2W 


91637 


CCF50-1-G33200F 


A1A1R 3037 


322-3314-00 






RE S,FXD:M ETAL FILM:18.2K OHM,1%,0.2W 


57668 


CRB20FXE 18K2 


A1A1R 3038 


322-3306-00 






RE S,FXD:M ETAL FILM:15.0K OHM,1%,0.2W 


57668 


CRB20FXE 15K0 


A1A1R 3039 


322-3327-00 






RES,FXD,FILM:24.9K OHM,1%,0.2W 


57668 


CRB20FXE 24K9 


A1A1R 3040 


322-3385-00 






RE S,FXD:M ETAL FILM:100K OHM,1%,0.2W 


57668 


CRB20FXE 100K 



8-14 



1502B MTDR Service Manual 



Replaceable Electrical Parts 



Replaceable Parts List (Cont.) 



Assy 

Number 


Tektronix 
Part Number 


Serial No. 
Effective 


Serial No. 
Discont’d 


Qty Name & Description 


Mfr. 

Code 


Mfr. Part Number 


A1A1 


670-9285-XX 






CIRCUIT BD ASSY:MAIN W/O EPROM (Con’t) 






A1A1R3041 


322-3126-00 






RES,FXD,FILM:200 OHM,1%,0.2W 


91637 


CCF501G200R0F 


A1A1R 3042 


322-3173-00 






RES,FXD,FILM:619 OHM ,1%,0.2W 


91637 


CCF50-2F619R0F 


A1A1R4020 


322-3297-00 






RE S,FXD:M ETAL FILM:12.1K OHM,1%,0.2W 


57668 


CRB20FXE 12K1 


A1A1R4021 


322-3261-00 






RES,FXD,FILM:5.11K OHM,1%,0.2W 


91637 


CCF50G5111FT 


A1A1R4022 


322-3385-00 






RE S,FXD:M ETAL FILM:100K OHM,1%,0.2W 


57668 


CRB20FXE 100K 


A1A1R4023 


322-3347-00 






RES,FXD,FILM:40.2K OHM,1%,0.2W 


91637 


CCF50-2-G40201F 


A1A1R4030 


322-3126-00 






RES,FXD,FILM:200 OHM ,1%,0.2W 


91637 


CCF501G200R0F 


A1A1R4031 


322-3325-00 






RES,FXD,FILM:23.7K OHM,1%,0.2W 


57668 


CRB20FXE 23K7 


A1A1R4032 


322-3261-00 






RES,FXD,FILM:5.11K OHM,1%,0.2W 


91637 


CCF50G5111FT 


A1A1R4040 


322-3281-00 






RES,FXD:M ETAL FILM:8.25K OHM,1%,0.2W 


57668 


CRB20FXE 8K25 


A1A1R4041 


322-3134-00 






RES,FXD,FILM:243 OHM ,1%,0.2W 


57668 


CRB20 FXE243E 


A1A1R4042 


322-3135-00 






RES,FXD,FILM:249 OHM ,1%,0.2W 


57668 


CRB20FXE 249E 


A1A1R4043 


321-0136-00 






RES,FXD,FILM:255 OHM,1%,0.125W 


19701 


5043ED255R0F 


A1A1R4044 


322-3137-00 






RES,FXD,FILM:261 OHM ,1%,0.2W 


57668 


CRB20FXE 261E 


A1A1R4045 


322-3138-00 






RES,FXD,FILM:267 OHM,1%,0.2W 


57668 


CRB20FXE 267E 


A1A1R4046 


322-3139-00 






RES,FXD:M ETAL FILM:274 OHM,1%,0.2W 


57668 


CRB20FXE 274E 


A1A1R4047 


322-3141-00 






RES,FXD,FILM:287 OHM,1%,0.2W 


57668 


CRB20FXE 287E 


A1A1R4048 


322-3001-00 






RES,FXD:METAL FILM:10 OHM ,1%,0.2W 


57668 


CRB20 FXE10E0 


A1A1R 5020 


322-3395-07 






RES,FXD,FILM:127K 0 H M , 1%,0.2W 


57668 


BZE127K 


A1A1R 5021 


322-3289-00 






RE S,FXD:M ETAL FILM:10.0K OHM,1%,0.2W 


57668 


CRB20FXE 10K0 


A1A1R 5022 


322-3337-00 






RES f FXD f FILM:31.6K OHM,1%,0.2W 


91637 


CCF502G31601FT 


A1A1R 5023 


322-3164-00 






RES,FXD,FILM:499 OHM ,1%,0.2W 


57668 


CRB20FXE 499E 


A1A1R 5024 


322-3001-00 






RE S,FXD:M ETAL FILM:10 OHM ,1%,0.2W 


57668 


CRB20 FXE10E0 


A1A1R 5025 


322-3001-00 






RE S,FXD:M ETAL FILM:10 OHM ,1%,0.2W 


57668 


CRB20 FXE10E0 


A1A1R 5026 


322-3068-00 


B021152 




RE S,FXD:M ETAL FILM:49.9 OHM,0.1%,0.2W 


57668 


CRB20FXE 49E9 


A1A1R 5030 


322-3280-00 






RES,FXD,FILM:8.06K OHM,1%,0.2W 


57668 


CRB20FXE 8K06 


A1A1R 5031 


322-3222-00 






RE S,FXD:M ETAL FILM:2.00K OHM,1%,0.2W 


57668 


CRB20FXE 2K00 


A1A1R 5032 


322-3097-00 






RE S,FXD:M ETAL FILM:100 OHM ,1%,0.2W 


57668 


CRB20FXE 100E 


A1A1R 5033 


322-3068-00 






RE S,FXD:M ETAL FILM:49.9 OHM,0.1%,0.2W 


57668 


CRB20FXE 49E9 


A1A1R 5034 


322-3184-00 






RES,FXD,FILM:806 OHM ,1%,0.2W 


57668 


CRB20FXE 806E 


A1A1R 5035 


322-3250-00 






RE S,FXD:M ETAL FILM:3.92K OHM,1%,0.2W 


91637 


CCF50-2F39200F 


A1A1R6030 


322-3068-00 






RE S,FXD:M ETAL FILM:49.9 OHM,0.1%,0.2W 


57668 


CRB20FXE 49E9 



1502B MTDR Service Manual 



8-15 



Replaceable Electrical Parts 



Replaceable Parts List (Cont.) 



Assy 

Number 


Tektronix 
Part Number 


Serial No. 
Effective 


Serial No. 
Discont’d 


Qty Name & Description 


Mfr. 

Code 


Mfr. Part Number 


A1A1 


670-9285-XX 






CIRCUIT BD ASSY:MAIN W/O EPROM (Con’t) 






A1A1R6031 


322-3262-00 






RES,FXD,FILM:5.23KOHM,1,0.2W 


57668 


CRB20FXE 5K23 


A1A1R6032 


322-3251-00 






RES,FXD,FILM:4.02KOHM,1%,0.2W 


57668 


CRB20FXE 4K02 


A1A1R6033 


322-3139-00 






RE S,FXD:M ETAL FILM:274 OHM,1%,0.2W 


57668 


CRB20FXE 274E 


A1A1R6040 


322-3222-00 






RE S,FXD:M ETAL FILM:2.00K OHM,1%,0.2W 


57668 


CRB20FXE 2K00 


A1A1R6041 


321-0960-07 






RES,FXD,FILM:513 OHM ,0.1%,0.125W 


01121 


ADVISE 


A1A1R6042 


322-3175-00 






RES,FXD,FILM:649 OHM ,1%,0.2W 


57668 


CRB20FXE 649E 


A1A1R6043 


322-3185-00 






RES,FXD:METAL FILM:825 OHM,1%,0.2W 


57668 


CRB20FXE 825E 


A1A1R6044 


322-3194-00 






RES I FXD,FILM:1.02K OHM,1%,0.2W 


91637 


CCF50-2G10200F 


A1A1R6045 


322-3204-00 






RES,FXD f F ILM :1.30K OHM,1%,0.2W 


57668 


CRB20FXE 1K30 


A1A1R6046 


322-3213-00 






RES,FXD,FILM:1.62KOHM,1%,0.2W 


57668 


CRB20FXE 1K62 


A1A1R6047 


322-3223-00 






RES,FXD,FILM:2.05K OHM,1%,0.2W 


57668 


CRB20FXE 2K05 


A1A1R7010 


322-3114-00 






RES,FXD:METAL FILM:150 OHM,1%,0.2W 


57668 


CRB20-FX150E 


A1A1R7011 


322-3097-00 






RES,FXD:METAL FILM:100 OHM,1%,0.2W 


57668 


CRB20FXE 100E 


A1A1R7012 


322-3097-00 






RES,FXD:M ETAL FILM:100 OHM,1%,0.2W 


57668 


CRB20FXE 100E 


A1A1R7013 


322-3105-00 






R E S ,FXDM ETAL FILM:121 OHM 1%,0.2W 


57668 


CRB20FXE 121E 


A1A1R 7014 


322-3154-00 






RES,FXD:M ETAL FILM:392 OHM,1%,0.2W 


57668 


RB20 FX392E 


A1A1R7015 


322-3154-00 






RES,FXD:M ETAL FILM:392 OHM,1%,0.2W 


57668 


RB20 FX392E 


A1A1R7020 


322-3310-00 






RES,FXD,FILM:16.5K OHM,1%,0.2W 


57668 


CRB20FXE 16K5 


A1A1R 7021 


321-0038-00 






RES,FXD,FILM:24.3 OHM ,1%,0.125W 


57668 


CRB14FXE 24.3 


A1A1R 7022 


322-3306-00 






RE S,FXD:M ETAL FILM:15.0K OHM,1%,0.2W 


57668 


CRB20FXE 15K0 


A1A1R 7023 


322-3097-00 






RE S,FXD:M ETAL FILM:100 OHM ,1%,0.2W 


57668 


CRB20FXE 100E 


A1A1R 7024 


322-3193-00 






RE S,FXD:M ETAL FILM :1K OHM,1%,0.2W 


57668 


CRB20FXE 1K00 


A1A1R 7025 


322-3193-00 






RE S,FXD:M ETAL FILM :1K OHM,1%,0.2W 


57668 


CRB20FXE 1K00 


A1A1R 7026 


322-3193-00 






RE S,FXD:M ETAL FILM :1K OHM,1%,0.2W 


57668 


CRB20FXE 1K00 


A1A1R 7027 


322-3097-00 






RE S,FXD:M ETAL FILM:100 OHM ,1%,0.2W 


57668 


CRB20FXE 100E 


A1A1R 7028 


322-3068-00 






RE S,FXD:M ETAL FILM:49.9 OHM,0.1%,0.2W 


57668 


CRB20FXE 49E9 


A1A1R 7029 


322-3342-00 






RES,FXD,FILM:35.7K OHM,1%,0.2W 


57668 


CRB20FXE 35K7 


A1A1R 7030 


322-3222-00 






RE S,FXD:M ETAL FILM:2.00K OHM,1%,0.2W 


57668 


CRB20FXE 2K00 


A1A1R 7031 


322-3306-00 






RE S,FXD:M ETAL FILM:15.0K OHM,1%,0.2W 


57668 


CRB20FXE 15K0 


A1A1R 7032 


321-0720-00 






RES,FXD,FILM:60K OHM ,1%,0.125W 


91637 


CMF55-116-G-60001FT 


A1A1R 7033 


322-3269-00 






RES,FXD,FILM:6.19K OHM,1%,0.2W 


91637 


CCF501G61900F 


A1A1R 7034 


322-3068-00 






RE S,FXD:M ETAL FILM:49.9 OHM,0.1%,0.2W 


57668 


CRB20FXE 49E9 



8 - 1 6 1 502B MTDR Service Manual 



Replaceable Electrical Parts 



Replaceable Parts List (Cont.) 



Assy 

Number 


Tektronix 
Part Number 


Serial No. 
Effective 


Serial No. 
Discont’d 


Qty Name & Description 


Mfr. 

Code 


Mfr. Part Number 


A1A1 


670-9285-XX 






CIRCUIT BD ASSY:MAIN W/O EPROM (Con’t) 






A1A1R7040 


322-3001-00 






RE S,FXD:M ETAL FILM:10 OHM ,1%,0.2W 


57668 


CRB20 FXE10E0 


A1A1R8010 


321-0038-00 






RES,FXD,FILM:24.3 OHM ,1%,0.125W 


57668 


CRB14FXE 24.3 


A1A1R8011 


321-0312-00 






RES,FXD,FILM:17.4K OH M ,1%,0.125W 


07716 


CEAD17401F 


A1A1R8012 


321-0631-00 






RES,FXD,FILM:12.5K OH M ,1%,0.125W 


07716 


CEA TO 1% 12.5K 


A1A1R8013 


322-3126-00 






RES,FXD,FILM:200 OHM ,1%,0.2W 


91637 


CCF501G200R0F 


A1A1R8014 


322-3068-00 


B021151 




RES,FXD:M ETAL FILM:49.9 OHM,0.1%,0.2W 


57668 


CRB20FXE49E9 


A1A1R8020 


322-3193-00 






RES,FXD:M ETAL FILM :1K OHM,1%,0.2W 


57668 


CRB20FXE 1K00 


A1A1R8021 


322-3325-00 






RES,FXD,FILM:23.7K OHM,1%,0.2W 


57668 


CRB20FXE 23K7 


A1A1R8022 


322-3283-00 






RES,FXD,FILM:8.66K OHM,1%,0.2W 


57668 


CRB20FXE 8K66 


A1A1R8023 


322-3289-00 






RES,FXD:M ETAL FILM:10.0K OHM,1%,0.2W 


57668 


CRB20FXE 10K0 


A1A1R8024 


322-3097-00 






RES,FXD:METAL FILM:100 OHM,1%,0.2W 


57668 


CRB20FXE 100E 


A1A1R8025 


321-0174-00 






RES,FXD,FILM:634OHM,l%,0.125W 


19701 


5043ED634ROF 


A1A1R8026 


322-3306-00 






RES,FXD:METAL FILM:15.0K OHM,1%,0.2W 


57668 


CRB20FXE 15K0 


A1A1R8027 


322-3306-00 






RES,FXD:M ETAL FILM:15.0K OHM,1%,0.2W 


57668 


CRB20FXE 15K0 


A1A1R8028 


322-3306-00 






RES,FXD:M ETAL FILM:15.0K OHM,1%,0.2W 


57668 


CRB20FXE 15K0 


A1A1R8040 


321-0058-00 


R010100 


B020616 


RES,FXD,FILM:2.74M OHM ,1%,0.125W 


80009 


321-0058-00 




321-0782-03 


B020617 


B020797 


RES,FXD,FILM:40 OHM, 0.25%, 0.125W 


03888 


PME5540 OHM 0.25 




321-0058-00 


B020798 


B020816 


RES,FXD,FILM:2.74M OHM ,1%,0.125W 


80009 


321-0058-00 




321-0782-03 


B020817 




RES,FXD ( FILM:40 OHM, 0.25%, 0.125W 


03888 


PME5540 OHM 0.25 


A1A1R8041 


322-3128-00 






RES,FXD,FILM:210 OHM ,1%,0.2W 


57668 


CRB20 FXE210E 


A1A1R8042 


322-3205-00 






RES,FXD,FILM:1.33K OHM,1%,0.2W 


57668 


CRB20FXE 1K33 


A1A1R8043 


321-0282-00 


R010100 


B020616 


RES,FXD,FILM:8.45K OH M ,1%,0.125W 


80009 


321-0282-00 




321-0620-00 


B020617 


B020797 


RES, FXD,FILM:8.45K OHM, 0.25%, 0.125W 


91637 


CMF55-116-D-84500CT 




321-0282-00 


B020798 


B020816 


RES,FXD,FILM:8.45K OHM,1%,0.125W 


80009 


321-0282-00 




321-0620-00 


B020817 




RES, FXD,FILM:8.45K OHM, 0.25%, 0.125W 


91637 


CMF55-116-D-84500CT 


A1A1R8044 


322-3318-00 






RE S,FXD:M ETAL FILM:20.0K OHM,1%,0.2W 


57668 


CRB20FXE 20K0 


A1A1R8045 


322-3318-00 






RE S,FXD:M ETAL FILM:20.0K OHM,1%,0.2W 


57668 


CRB20FXE 20K0 


A1A1R8046 


322-3318-00 






RE S,FXD:M ETAL FILM:20.0K OHM,1%,0.2W 


57668 


CRB20FXE 20K0 


A1A1R8047 


322-3289-00 






RE S,FXD:M ETAL FILM:10.0K OHM,1%,0.2W 


57668 


CRB20FXE 10K0 


A1A1R9010 


322-3114-00 






RE S,FXD:M ETAL FILM:150 OHM,1%,0.2W 


57668 


CRB20-FX150E 


A1A1R9011 


322-3258-00 






RE S,FXD:M ETAL FILM:4.75K OHM,1%,0.2W 


56845 


CCF50-2-G4751FT 


A1A1R9012 


322-3143-00 






RES,FXD,FILM:301 OHM,1%,0.2W 


57668 


CRB20FXE 301E 



1502B MTDR Service Manual 



8-17 



Replaceable Electrical Parts 



Replaceable Parts List (Cont.) 



Assy 

Number 


Tektronix 
Part Number 


Serial No. 
Effective 


Serial No. 
Discont’d 


Qty Name & Description 


Mfr. 

Code 


Mfr. Part Number 


A1A1 


670-9285-XX 






CIRCUIT BD ASSY:MAIN W/O EPROM (Con’t) 






A1A1R9013 


322-3306-00 






RE S,FXD:M ETAL FILM:15.0K OHM,1%,0.2W 


57668 


CRB20FXE 15K0 


A1A1R9014 


322-3310-00 






RES,FXD,FILM:16.5KOHM,1%,0.2W 


57668 


CRB20FXE 16K5 


A1A1R9015 


322-3342-00 






RES,FXD,FILM:35.7K OHM,1%,0.2W 


57668 


CRB20FXE 35K7 


A1A1R9020 


321-0038-00 






RES,FXD,FILM:24.3 OHM ,1%,0.125W 


57668 


CRB14FXE 24.3 


A1A1R9021 


322-3097-00 






RE S,FXD:M ETAL FILM:100 OHM ,1%,0.2W 


57668 


CRB20FXE 100E 


A1A1R9022 


322-3280-00 






RES,FXD,FILM:8.06K OHM,1%,0.2W 


57668 


CRB20FXE 8K06 


A1A1R9023 


322-3097-00 






RES,FXD:METAL FILM:100 OHM,1%,0.2W 


57668 


CRB20FXE 100E 


A1A1R9024 


322-3222-00 






RES,FXD:M ETAL FILM:2.00K OHM,1%,0.2W 


57668 


CRB20FXE 2K00 


A1A1R9025 


322-3306-00 






RES,FXD:METAL FILM:15.0K OHM,1%,0.2W 


57668 


CRB20FXE 15K0 


A1A1R9026 


322-3234-00 






RES,FXD,FILM:2.67K OHM,1%,0.2W 


91637 


CCF50-2F26700F 


A1A1R9027 


322-3126-00 






RES,FXD,FILM:200 OHM ,1%,0.2W 


91637 


CCF501G200R0F 


A1A1R9030 


322-3371-00 






RES,FXD,FILM:71.5K OHM,1%,0.2W 


57668 


CRB20FXE 71K5 


A1A1R9031 


322-3331-00 






RES,FXD:METAL FILM:27.4K OHM,1%,0.2W 


57668 


CRB20FXE 27K4 


A1A1R9032 


311-0633-00 






RES,VAR,NONWW:TRMR,5K OHM,0.5W CERMET 


32997 


3329H-L58-502 


A1A1TP 1040 


214-0579-02 


B010100 


B037260 


TERM, TEST POINT:0.052 ID, 0.169 H, 0.465 L 


10392 


7-16150-8 


A1A1TP 1041 


214-0579-02 


B010100 


B037260 


TERM, TEST POINT:0.052 ID, 0.169 H, 0.465 L 


10392 


7-16150-8 


A1A1TP 2040 


214-0579-02 


B010100 


B037260 


TERM, TEST POINT:0.052 ID, 0.169 H, 0.465 L 


10392 


7-16150-8 


A1A1TP 3040 


214-0579-02 


B010100 


B037260 


TERM, TEST POINT:0.052 ID, 0.169 H, 0.465 L 


10392 


7-16150-8 


A1A1TP 3041 


214-0579-02 


B010100 


B037260 


TERM, TEST POINT:0.052 ID, 0.169 H, 0.465 L 


10392 


7-16150-8 


A1A1TP 4020 


214-0579-02 


B010100 


B037260 


TERM, TEST POINT:0.052 ID, 0.169 H, 0.465 L 


10392 


7-16150-8 


A1A1TP 4021 


214-0579-02 


B010100 


B037260 


TERM, TEST POINT:0.052 ID, 0.169 H, 0.465 L 


10392 


7-16150-8 


A1A1TP 4040 


214-0579-02 


B010100 


B037260 


TERM, TEST POINT:0.052 ID, 0.169 H, 0.465 L 


10392 


7-16150-8 


A1A1TP 6010 


214-0579-02 


B010100 


B037260 


TERM, TEST POINT:0.052 ID, 0.169 H, 0.465 L 


10392 


7-16150-8 


A1A1TP 7010 


214-0579-02 


B010100 


B037260 


TERM, TEST POINT:0.052 ID, 0.169 H, 0.465 L 


10392 


7-16150-8 


A1A1TP 9010 


214-0579-02 


B010100 


B037260 


TERM, TEST POINT:0.052 ID, 0.169 H, 0.465 L 


10392 


7-16150-8 


A1A1TP 9011 


214-0579-02 


B010100 


B037260 


TERM, TEST POINT:0.052 ID, 0.169 H, 0.465 L 


10392 


7-16150-8 


A1A1TP 9040 


214-0579-02 


B010100 


B037260 


TERM, TEST POINT:0.052 ID, 0.169 H, 0.465 L 


10392 


7-16150-8 


A1A1TP 9041 


214-0579-02 


B010100 


B037260 


TERM, TEST POINT:0.052 ID, 0.169 H, 0.465 L 


10392 


7-16150-8 


A1A1U 1010 


156-2760-00 






1C, DIGITAL:CMOS,MISC;NONVOLATILE CONTROL 


0B0A9 


DS 1210 


A1A1U1011 


156-2763-00 






IC,DIGITAL:HCMOS,FLIP FLOP ;DUAL J - K 


04713 


MC74HC113N 


A1A1U 1012 


156-1225-00 






1C ,LIN E AR :BIP OLAR,CO M P ARATO R;DU AL 


01295 


LM393P 



8-18 



1502B MTDR Service Manual 



Replaceable Electrical Parts 



Replaceable Parts List (Cont.) 



Assy 

Number 


Tektronix 
Part Number 


Serial No. 
Effective 


Serial No. 
Discont’d 


Qty Name & Description 


Mfr. 

Code 


Mfr. Part Number 


A1A1 


670-9285-XX 






CIRCUIT BD ASSY:MAIN W/O EPROM (Con’t) 






A1A1U1020 


156-2473-00 






IC,M EMORY :C M 0 S ,S R AM ;8K X 8,200NS,200NA 


0JR04 


TC5564PL-20 


A1A1U 1021 


156-2473-00 






IC,M EMORY :C M 0 S ,S R AM ;8K X 8,200NS,200NA 


0JR04 


TC5564PL-20 


A1A1U 1022 


156-2583-00 






IC,DIGITAL:HCMOS,DE MUX/DE CODER 


01295 


SN74HC138N 


A1A1U 1023 


156-2587-00 






1C ,DGTL:C P U 6MHZ,Z-80 DIP40 


0JR04 


TMPZ84C00AP-6 


A1A1U 1030 


156-1397-00 






1C ,DIG ITAL:C M OS ,G ATE S ;8- IN P UT NAND 


27014 


MM74C30N 


A1A1U 1031 


156-2392-00 






IC,DIG ITAL:HC MOS,G ATE;H EX INV, SCHMITT TRIG 


04713 


MC74HC14N 


A1A1U 1032 


156-1994-00 






IC,DIGITAL:CMOS,BUFFER/DRIVER;OCTAL INV 


27014 


MM74C240 


A1A1U 1034 


156-0991-02 






IC,LINEAR:VOLTAGE REGULATOR 


04713 


MC78L05ACPRP 


A1A1U 1040 


156-3058-00 






IC,DIGITAL:HCMOS,GATE;DUAL 4-INPUT NAND 


01295 


SN74HC20N 


A1A1U 1041 


156-2009-00 






IC,DIGITAL:HCMOS,FLIP FLOP ;DU AL D-TYP 


01295 


SN74HC74N 


A1A1U 1042 


156-3180-00 






1C, DIG ITAL:HCMOS, GATE TRIPLE 3-INPUT NOR 


04713 


MC74HC27N 


A1A1U 1043 


156-2463-00 






IC,DITIAL:HCMOS ,G ATE ;QU AD 2-INPUT OR 


01295 


SN74HC32N 


A1A1U 2011 


156-2415-00 






1C, DIG ITAL:HCMOS, TRANS CEIVER;OCTAL, NON INV 


04713 


MC74HC245AN 


A1A1U 2012 


156-3110-00 






IC,DIGITAL:HCMOS,BUFFER;NONINV OCTAL 


27014 


MM74HC244N 




136-0755-00 






SOCKET, DIP:PCB, 28 POS,2 X 14,0.1 X 0.6 CTR 


09922 


DILB28P-108 


A1A1U 2021 


156-2583-00 






1C, DIG ITAL:HCMOS, DEMUX/DE CODER 


01295 


SN74HC138N 


A1A1U 2022 


156-2583-00 






1C, DIG ITAL:HCMOS, DEMUX/DE CODER 


01295 


SN74HC138N 


A1A1U 2023 


156-2009-00 






IC,DIGITAL:HCMOS,FLIP FLOP ;DU AL D-TYP 


01295 


SN74HC74N 


A1A1U 2024 


156-2583-00 






1C, DIG ITAL:HCMOS, DEMUX/DE CODER 


01295 


SN74HC138N 


A1A1U 2025 


156-2763-00 






IC,DIGITAL:HCMOS,FLIP FLOP ;DUAL J - K 


04713 


MC74HC113N 


A1A1U 2026 


156-2583-00 






IC,DIGITAL:HCMOS,DE MUX/DE CODER 


01295 


SN74HC138N 


A1A1U 2027 


156-2763-00 






IC,DIGITAL:HCMOS,FLIP FLOP ;DUAL J - K 


04713 


MC74HC113N 


A1A1U2030 


156-2767-00 






1C, DGTL:CHMOS, COUNTER TIMER 82C54 


34649 


P82C54 


A1A1U 2031 


119-2736-00 






CRYSTAL, SCOPE 


75378 


MXO-55GA-3I-20M 


A1A1U 2032 


156-2096-00 






1C ,DIG ITAL:ALSTTL,F LIP FLOP ;QU AD D-TYPE 


01295 


SN74ALS175N 


A1A1U 2033 


156-2759-00 






1C ,DIG ITAL:ALSTTL,F LIP FLOP ;DU AL J - K 


01295 


74ALS113 


A1A1U 2034 


156-2092-00 






IC,DIGITAL:ALSTTL,GATE;QUAD 2-INPUT NOR 


01295 


SN74ALS02N 


A1A1U 2036 


156-2096-00 






1C ,DIG ITAL:ALSTTL,F LIP FLOP ;QU AD D-TYPE 


01295 


SN74ALS175N 


A1A1U 2037 


156-2098-00 






IC,DIGITAL:ALSTTL,COUNTER;SYNCH 4- BIT 


01295 


SN74ALS161BN 


A1A1U 2040 


156-2437-00 






IC,DIGITAL:HCTCMOS,GATE;QUAD 2-INPUT AND 


34371 


CD74HCT08E17 


A1A1U 2041 


156-2768-00 






IC,LINEAR:12 BIT PLUS SIGN 1205 


27014 


ADC1205 


A1A1U 2042 


156-2759-00 






1C ,DIG ITAL:ALSTTL,F LIP FLOP ;DU AL J - K 


01295 


74ALS113 



1502B MTDR Service Manual 



8-19 



Replaceable Electrical Parts 



Replaceable Parts List (Cont.) 



Assy 

Number 


Tektronix 
Part Number 


Serial No. 
Effective 


Serial No. 
Discont’d 


Qty Name & Description 


Mfr. 

Code 


Mfr. Part Number 


A1A1 


670-9285-XX 






CIRCUIT BD ASSY:MAIN W/O EPROM (Con’t) 






A1A1U 2043 


156-2421-00 






IC,DIGITAL:HCMOS,FLIP FLOP ;QUAD D-TYPE 


04713 


MC74HC175N 


A1A1U 2044 


156-3107-00 






IC,DIGITAL:HCMOS,FLIP FLOP;OCTAL D-TYPE 


01295 


SN74HC374N 


A1A1U 2045 


156-1752-00 






1C, DIG ITAL:FTTL, GATE TRIPLE 3-INPUT NAND 


04713 


MC 74F10N 


A1A1U 2046 


156-3151-00 






ICJNTFC :CMOS,D/A CONVERTER 


24355 


AD7534J N 


A1A1U 3010 


156-3107-00 






IC,DIGITAL:HCMOS,FLIP FLOP;OCTAL D-TYPE 


01295 


SN74HC374N 


A1A1U 3020 


156-2026-00 






IC,DIGITAL:HCMOS,GATE;QUAD 2-INPUT NOR 


04713 


MC74HC02AN 


A1A1U 3021 


156-3107-00 






IC,DIGITAL:HCMOS,FLIP FLOP;OCTAL D-TYPE 


01295 


SN74HC374N 


A1A1U 3022 


156-2421-00 






IC,DIGITAL:HCMOS,FLIP FLOP ;Q U AD D-TYPE 


04713 


MC74HC175N 


A1A1U 3023 


156-0927-00 






IC,LINEAR:DIGITAL TO ANALOG CONVERTER 


04713 


MC3410CL 


A1A1U 3040 


156-1173-00 






IC ( UNEAR:BIPOLAR; VOLT REF;POS, 2.5V, 1.0% 


04713 


MC1403U 


A1A1U 3041 


156-0854-00 






1C, LINEAR:BIPOLAR, OP-AMP 


24355 


OP08FP OR PM308-026P 


A1A1U 3042 


156-1114-00 






IC,LINEAR:MOS/FET INP,COS/MOS OUT, OP AMP 


34371 


CA3160E 


A1A1U4020 


156-3151-00 






IC,INTFC:CMOS,D/A CONVERTER 


24355 


AD7534J N 


A1A1U4021 


156-1699-00 






IC,LINEAR:DUAL B 1- F ET,0 P N L AM P L, LOW OFFSET 


01295 


TL288CP 


A1A1U4040 


156-0513-00 






1C, MISC:CMOS, ANALOG MUX;8 CHANNEL 


04713 


MC14051BCP 


A1A1U 5010 


156-0854-00 






1C, LINEAR:BIPOLAR, OP-AMP 


24355 


OP08FP OR PM308-026P 


A1A1U 5020 


156-1156-00 






IC,LINEAR:BIFET,OP-AMP;;LF356N,DIP08.3 


04713 


LF356N 


A1A1U 5040 


156-1114-00 






IC,LINEAR:MOS/FET INP,COS/MOS OUT, OP AMP 


34371 


CA3160E 


A1A1U 6040 


156-0513-00 






1C, MISC:CMOS, ANALOG MUX;8 CHANNEL 


04713 


MC14051BCP 


A1A1U 7010 


156-2763-00 






IC,DIGITAL:HCMOS,FLIP FLOP ;DUAL J - K 


04713 


MC74HC113N 


A1A1U7040 


156-1114-00 






IC,LINEAR:MOS/FET INP,COS/MOS OUT, OP AMP 


34371 


CA3160E 


A1A1U 8010 


156-1707-00 






1C ,DIG ITAL:FTTL,G ATE;QUAD 2-INPUT NAND 


04713 


MC74F00 (N OR J ) 


A1A1U 8040 


156-0513-00 






1C, MISC:CMOS, ANALOG MUX;8 CHANNEL 


04713 


MC14051BCP 


A1A1U 8041 


156-1114-00 






IC,LINEAR:MOS/FET INP,COS/MOS OUT, OP AMP 


34371 


CA3160E 


A1A1U 9030 


156-0496-00 






IC,LINEAR:VOLTAGE REGULATOR RC4194D,MI 


34333 


SG4194CJ 


A1A1VR 3030 


152-0647-00 






DIODE,ZENER:6.8V,5%,0.4W;1N957B 


04713 


1N957B 


A1A1VR 6030 


152-0514-00 






DIODE, ZENER:10V,1%,0.4W;MZ4104D 


04713 


MZ4104D 



8-20 



1502B MTDR Service Manual 



Replaceable Electrical Parts 



Replaceable Parts List (Cont.) 



Assy 

Number 


Tektronix 
Part Number 


Serial No. 
Effective 


Serial No. 
Discont’d 


Qty Name & Description 


Mfr. 

Code 


Mfr. Part Number 


A2 


672-1 251 -XX 






CIRCUIT BD ASSY:FRONT PANEL 






A2C1011 


283-0359-00 






CAP ,FXD,C E R DhlOOOP F f 10%,200V SQUARE 


18796 


RPE112NPO 102K200V 


A2C1015 


283-0359-01 


B020820 




CAP ,FXD,C E R DhlOOOP F f 5%,200V SQUARE 


31433 


C322C102J 2G5CA 


A2C2010 


281-0925-01 






CAP f FXD,C E R DI:M LC.0.22UF f 20%,50V f ZRU 


31433 


C114C224M5Y5CA 


A2C2011 


281-0925-01 






CAP,FXD,CER DI:M LC.0.22UF f 20%,50V f ZRU 


31433 


C114C224M5Y5CA 


A2C2020 


281-0925-01 






CAP,FXD,CER DI:M LC.0.22UF f 20%,50V f ZRU 


31433 


C114C224M5Y5CA 


A2C2021 


290-0974-00 






CAP,FXD,ELCTLT :10U F ,20%,50VDC AL 


55680 


UVX1H100MAA 


A2C2022 


290-0974-00 






CAP,FXD,ELCTLT :10U F ,20%,50VDC AL 


55680 


UVX1H100MAA 


A2C2023 


281-0925-01 






C AP ,FXD,C E R DI:MLC,0.22UF ,20%,50V f ZRU 


31433 


C114C224M5Y5CA 


A2C2024 


281-0925-01 






C AP ,FXD f C E R DI:MLC,0.22UF ,20%,50V f ZRU 


31433 


C114C224M5Y5CA 


A2C2025 


283-0492-00 






C AP ,FXD,C E R DhlOOOP F ,20% DIP STYLE 


04222 


MD015C102MAA 


A2C2026 


283-0492-00 






C AP ,FXD,C E R DhlOOOP F ,20% DIP STYLE 


04222 


MD015C102MAA 


A2C2027 


283-0492-00 






C AP ,FXD,C E R DhlOOOP F ,20% DIP STYLE 


04222 


MD015C102MAA 


A2C2028 


283-0492-00 






C AP ,FXD,C E R DhlOOOP F ,20% DIP STYLE 


04222 


MD015C102MAA 


A2C2030 


281-0925-01 






C AP ,FXD,C E R DI:MLC,0.22UF ,20%,50V f ZRU 


31433 


C114C224M5Y5CA 


A2C2031 


283-0492-00 






C AP ,FXD,C E R DhlOOOP F ,20% DIP STYLE 


04222 


MD015C102MAA 


A2C2032 


283-0492-00 






C AP ,FXD,C E R DhlOOOP F ,20% DIP STYLE 


04222 


MD015C102MAA 


A2C2033 


281-0925-01 






C AP ,FXD,C E R DI:MLC,0.22UF ,20%,50V f ZRU 


31433 


C114C224M5Y5CA 


A2C2034 


281-0925-01 






C AP ,FXD,C E R DI:MLC,0.22UF ,20%,50V f ZRU 


31433 


C114C224M5Y5CA 


A2C3010 


281-0925-01 






CAP ,FXD,C E R DI:MLC,0.22UF ,20%,50V f ZR U 


31433 


C114C224M5Y5CA 


A2C3020 


281-0925-01 






CAP ,FXD f C E R DI:MLC,0.22UF ,20%,50V f ZR U 


31433 


C114C224M5Y5CA 


A2C3021 


281-0925-01 






CAP ,FXD f C E R DI:MLC,0.22UF f 20%,50V f ZRU 


31433 


C114C224M5Y5CA 


A2C3022 


281-0925-01 






CAP ,FXD,C E R DI:MLC,0.22UF ,20%,50V f ZR U 


31433 


C114C224M5Y5CA 


A2C3023 


281-0925-01 






CAP ,FXD,C E R DI:MLC,0.22UF f 20%,50V f ZRU 


31433 


C114C224M5Y5CA 


A2C3030 


290-0919-00 






CAP,FXD,ELCTLT:470UF ,+50- 20%,35V AL 


1W344 


KM E 35VB471M 10X20LL 


A2C3031 


290-0919-00 






CAP,FXD,ELCTLT:470UF ,+50- 20%,35V AL 


1W344 


KM E 35VB471M 10X20LL 


A2C3032 


281-0925-01 






CAP ,FXD f C E R DI:MLC,0.22UF ,20%,50V f ZRU 


31433 


C114C224M5Y5CA 


A2C3033 


281-0925-01 






CAP ,FXD f C E R DI:MLC,0.22UF ,20%,50V f ZRU 


31433 


C114C224M5Y5CA 


A2C3034 


281-0925-01 






CAP ,FXD f C E R DI:MLC,0.22UF ,20%,50V f ZRU 


31433 


C114C224M5Y5CA 


A2J 1020 


131-3147-00 






CONN, HDR:PCB, MALE, STR,2 X 25,0.1 CTR 


22526 


66506-032 


A2J 3030 


131-1857-00 






CONN, HDR:PCB, MALE, STR,1 X 36,0.1 CTR 


58050 


082-3644-SS10 



1502B MTDR Service Manual 



8-21 



Replaceable Electrical Parts 



Replaceable Parts List (Cont.) 



Assy 

Number 


Tektronix 
Part Number 


Serial No. 
Effective 


Serial No. 
Discont’d 


Qty Name & Description 


Mfr. 

Code 


Mfr. Part Number 


A2 


672-1 251 -XX 






CIRCUIT BD ASSY:FRONT PANEL (Con’t) 






A2PS2030 


119-2370-00 






CONVERTERS - AC, 15V IN, 80V AT 400 HZ 


63312 


LP S 15- 1-2 


A2Q1020 


151-1176-00 






XSTR,PWR:MOS,P-C H;100V,1.0A,0.6 OHM 


04713 


IRFD9120 


A2Q1030 


151-1176-00 






XSTR,PWR:MOS,P-C H;100V,1.0A,0.6 OHM 


04713 


IRFD9120 


A2Q2020 


151-1121-01 






XSTR,PWR:MOS,N-C H ,60V,0.5A,3.0 OHM 


17856 


VN0606L-TA 


A2R1010 


322-3385-00 






RES,FXD:METAL FILM:100K OHM,1%,0.2W 


57668 


CRB20FXE 100K 


A2R1011 


321-0816-00 






RES,FXD,FILM:5K 0 H M ,1%,0.125W 


01121 


ADVISE 


A2R1012 


322-3097-00 






RES,FXD:M ETAL F ILM :100 0 HM ,1%,0.2W 


5768 


CRB20FXE 100E 


A2R1013 


322-3347-00 






RES,FXD,FILM:40.2K OHM,1%,0.2W 


91637 


CCF50-2-G40201F 


A2R1018 


311-1337-00 






RES,VAR,NONWW:TRMR,25K OHM, 0.5W CERMET 


02111 


43P253T672 


A2R1020 


322-3097-00 






RES,FXD:METAL F ILM :100 0 HM ,1%,0.2W 


5768 


CRB20FXE 100E 


A2R1021 


322-3385-00 






RES,FXD:METAL FILM:100K OHM,1%,0.2W 


57668 


CRB20FXE 100K 


A2R1022 


311-2400-00 






RES,VAR,PLASTIC:DUAL 10K,10% NO STOPS 


12697 


CM45241 


A2R1023 


322-3385-00 






RES,FXD:M ETAL FILM:100K OHM,1%,0.2W 


57668 


CRB20FXE 100K 


A2R1024 


322-3385-00 






RES,FXD:M ETAL FILM:100K OHM,1%,0.2W 


57668 


CRB20FXE 100K 


A2R1025 


322-3385-00 






RES,FXD:M ETAL FILM:100K OHM,1%,0.2W 


57668 


CRB20FXE 100K 


A2R1026 


322-3385-00 






RES,FXD:M ETAL FILM:100K OHM,1%,0.2W 


57668 


CRB20FXE 100K 


A2R1027 


322-3385-00 






RES,FXD:M ETAL FILM:100K OHM,1%,0.2W 


57668 


CRB20FXE 100K 


A2R1030 


322-3385-00 






RE S,FXD:M ETAL FILM:100K OHM,1%,0.2W 


57668 


CRB20FXE 100K 


A2R1031 


322-3059-00 






RES,FXD,FILM:40.2 OHM ,1%,0.2W 


91637 


CCF50-2G40R020FT 


A2R2010 


322-3385-00 






RE S,FXD:M ETAL FILM:100K OHM,1%,0.2W 


57668 


CRB20FXE 100K 


A2R2020 


322-3001-00 






RE S,FXD:M ETAL FILM:10 OHM ,1%,0.2W 


57668 


CRB20FXE 10E0 


A2R2021 


322-3385-00 






RE S,FXD:M ETAL FILM:100K OHM,1%,0.2W 


57668 


CRB20FXE 100K 


A2R2022 


321-0523-00 






RES,FXD,FILM:2.74M OHM ,1%,0.125W 


07716 


CEA 2.74 M OHM 


A2R2024 


311-2400-00 






RES,VAR,PLASTIC:DUAL 10K,10% NO STOPS 


12697 


CM45241 


A2R2030 


322-3385-00 






RE S,FXD:M ETAL FILM:100K OHM,1%,0.2W 


57668 


CRB20FXE 100K 


A2R2031 


322-3385-00 






RE S,FXD:M ETAL FILM:100K OHM,1%,0.2W 


57668 


CRB20FXE 100K 


A2R2032 


322-3347-00 






RES,FXD,FILM:40.2K OHM,1%,0.2W 


91637 


CCF50-2-G40201F 


A2R2034 


322-3385-00 






RE S,FXD:M ETAL FILM:100K OHM,1%,0.2W 


57668 


CRB20FXE 100K 


A2R2035 


322-3385-00 






RE S,FXD:M ETAL FILM:100K OHM,1%,0.2W 


57668 


CRB20FXE 100K 


A2R2036 


322-3385-00 






RE S,FXD:M ETAL FILM:100K OHM,1%,0.2W 


57668 


CRB20FXE 100K 


A2R2037 


322-3385-00 






RE S,FXD:M ETAL FILM:100K OHM,1%,0.2W 


57668 


CRB20FXE 100K 



8-22 



1502B MTDR Service Manual 



Replaceable Electrical Parts 



Replaceable Parts List (Cont.) 



Assy 

Number 


Tektronix 
Part Number 


Serial No. 
Effective 


Serial No. 
Discont’d 


Qty Name & Description 


Mfr. 

Code 


Mfr. Part Number 


A2 


672-1 251 -XX 






CIRCUIT BD ASSY:FRONT PANEL (Con’t) 






A2R3010 


322-3385-00 






RE S,FXD:M ETAL FILM:100K OHM,1%,0.2W 


57668 


CRB20FXE 100K 


A2R3011 


322-3385-00 






RE S,FXD:M ETAL FILM:100K OHM,1%,0.2W 


57668 


CRB20FXE 100K 


A2R3020 


311-2400-00 






RES ,VAR ,P LASTIC :DU AL 10K f 10% NO STOPS 


12697 


CM45241 


A2R3024 


307-0504-00 






RES NTWK,FXD,FI:(15) 300K OHM,2%,0.125W 


01121 


316A304 


A2R3031 


307-0504-00 






RES NTWK,FXD,FI:(15) 300K OHM,2%,0.125W 


01121 


316A304 


A2RT2038 


307-0751-00 






RES,THERMAL:20K OHM, 5% 


56866 


QTMC-19J 


A2S1010 


260-2091-00 






SWITCH, PUSH:1 BTN,1 POLE RECORD/SWEEP 


71590 


2LL199NB021074 


A2S1011 


260-2091-00 






SWITCH, PUSH:1 BTN ,1 POLE RECORD/SWEEP 


71590 


2LL199NB021074 


A2S2010 


260-2091-00 






SWITCH, PUSH:1 BTN ,1 POLE RECORD/SWEEP 


71590 


2LL199NB021074 


A2S2011 


260-2091-00 






SWITCH, PUSH:1 BTN ,1 POLE RECORD/SWEEP 


71590 


2LL199NB021074 


A2S3010 


260-2091-00 






SWITCH, PUSH:1 BTN ,1 POLE RECORD/SWEEP 


71590 


2LL199NB021074 


A2S3012 


260-2269-00 


R010100 


B020819 


SWITCH, ROTARY:NOISE PC MOUNT 


81073 


51YY23669 




260-2269-01 


B020820 




SWITCH, ROTARY:NOISE PC MOUNT 


04426 


47-012-0014 


A2S3020 


260-2270-00 


R010100 


B020819 


SWITCH, ROTARY:HORIZONTAL SCALE 


81073 


51YY23673 




260-2270-01 


B020820 




SWITCH, ROTARY:HORIZONTAL SCALE 


04426 


47-006-0065 


A2S3021 


260-2287-00 


R010100 


B020819 


SWITCH, ROTARY:VP COURSE 


81073 


51YY23671 




260-2287-01 


B020820 




SWITCH, ROTARY:VP COURSE 


04426 


47-012-0011 


A2S3022 


260-2269-00 


R010100 


B020819 


SWITCH, ROTARY:NOISE PC MOUNT 


81073 


51YY23669 




260-2269-01 


B020820 




SWITCH, ROTARY:NOISE PC MOUNT 


04426 


47-012-0014 


A2U2010 


156-0853-00 






IC,LINEAR:BIPO LAR ,0 P - AM P ;DU AL 


18324 


NE532 


A2U2020 


156-1225-00 






1C ,LIN E AR :BIP OLAR,CO M P ARATO R;DU AL 


04713 


LM393N 


A2U2021 


156-1367-00 






IC,CONVERTER:CMOS,D/A;8 BIT,400NS 


24355 


AD7524J N 


A2U2022 


156-2463-00 






IC,DIGTIAL:HCMOS,GATE;QUAD 2-INPUT OR 


01295 


SN74HC32N 


A2U2023 


156-2589-00 






IC,CONVERTER:TTL,A/D;8-BIT,100US,SAR 


80009 


156-2589-00 


A2U2024 


156-2758-00 






IC,DIGITAL:HCMOS,MUX/ENCODER;DUAL 


0JR04 


TC74HC253AP 


A2U2025 


156-2758-00 






IC,DIGITAL:HCMOS,MUX/ENCODER;DUAL 


0JR04 


TC74HC253AP 


A2U3020 


156-2026-00 






IC,DIGITAL:HCMOS,GATE;QUAD 2-INPUT NOR 


04713 


MC74HC02AN 


A2U3021 


156-2026-00 






IC,DIGITAL:HCMOS,GATE;QUAD 2-INPUT NOR 


04713 


MC74HC02AN 


A2U3022 


156-2026-00 






IC,DIGITAL:HCMOS,GATE;QUAD 2-INPUT NOR 


04713 


MC74HC02AN 



1502B MTDR Service Manual 



8-23 



Replaceable Electrical Parts 



Replaceable Parts List (Cont.) 



Assy 

Number 


Tektronix 
Part Number 


Serial No. 
Effective 


Serial No. 
Discont’d 


Qty Name & Description 


Mfr. 

Code 


Mfr. Part Number 


A2 


672-1 251 -XX 






CIRCUIT BD ASSY:FRONT PANEL (Con’t) 






A2U3023 


156-2026-00 






1C ,DIG ITAL:HC MOS ,G ATE ;Q UAD 2-INPUT NOR 


04713 


MC74HC02AN 


A2U3025 


156-2758-00 






IC,DIGITAL:HCMOS,MUX/ENCODER;DUAL 


0JR04 


TC74HC253AP 


A2U3031 


156-2758-00 






IC,DIGITAL:HCMOS,MUX/ENCODER;DUAL 


0JR04 


TC74HC253AP 



8-24 



1502B MTDR Service Manual 



Replaceable Electrical Parts 



Replaceable Parts List (Cont.) 



Assy 

Number 


Tektronix 
Part Number 


Serial No. 
Effective 


Serial No. 
Discont’d 


Qty Name & Description 


Mfr. 

Code 


Mfr. Part Number 


A3 


620-0477-XX 






POWER SUPPLY ASSEMBLY 














CHASSIS MOUNTED ELECTRICAL PARTS 






A3C102 


283-0024-00 






CAP ,F XD,C E R DLO.IUF ,+80- 20%,50V 


80009 


283-0024-00 


A3C201 


283-0167-00 


B025000 


B037302 


CAP ,F XD,C E R DLO.IUF ,10%,100V 


80009 


283-0167-00 


A3F101 


159-0029-01 






FUSE CARTRIDGE:BUSSMAN ONLY 


80009 


159-0029-01 


A3F101 


159-0054-00 






FUSE CARTRIDGE:3AG,0.15A, 250V 


80009 


159-0054-00 


A3FL1 


119-1957-00 


R010100 


B024999 


FILTER, RFI:1A,250VAC,PWR CONN 


80009 


119-1957-00 




119-3488-00 


B025000 




FILTER, RFI:1A,115/230VAC,50/60HW 


80009 


119-3488-00 


A3L201 


120-1458-00 


B025000 


B037302 


XFMR,RF:TOROID 1980,TD-415 


80009 


120-1458-00 


A3R101 


307-0449-00 






RES, VSENSITIVE:1900PF,100A, 130V 


80009 


307-0449-00 


A3S201 


260-2372-00 






SWITCH, ROTARY:VOLTAGE SELECTOR 


80009 


260-2372-00 


A3T201 


120-1607-00 


B010100 


B037302 


XFMR,PWR:DUAL PRI 115/230VAC ,50/60HZ 


80009 


120-1607-00 




120-1922-00 


B037303 




XFMR,PWR:DUAL PRI 115/230VAC ,50/60HZ 


80009 


120-1922-00 


A3A1 


670-9286-XX 






CIRCUIT BD ASSY:POWER SUPPLY 






A3A1C 1010 


290-0997-00 






CAP,FXD,ELCTLT :3000U F ,- 10% +75%, 75V 


24165 


53D268 


A3A1C 1011 


283-0220-02 






CAP ,F XD,C E R DI:0.01U F,20%,50V 


04222 


AR205C 103MAATRSTDII 


A3A1C 1012 


283-0359-01 






CAP ,F XD,C E R DLIOOOP F ,5%,200V 


31433 


C322C102J 2G5CA 


A3A1C 1013 


281-0925-01 






CAP ,F XD,C E R DI:MLC,0.22UF,20%,50V 


31433 


C114C224M5Y5CA 


A3A1C 1014 


283-0359-01 






CAP ,F XD,C E R DLIOOOP F ,5%,200V 


31433 


C322C102J 2G5CA 


A3A1C 1015 


283-0359-01 






CAP ,F XD,C E R DhlOOOP F ,5%,200V 


31433 


C322C102J 2G5CA 


A3A1C 1016 


283-0107-00 






CAP ,F XD,C E R DI:51P F ,5%,200V 


04222 


SR202A510J AA 


A3A1C 1030 


283-0059-02 






CAP ,F XD,C E R DI:1UF,20%,50V 


04222 


S R 305C 105MAATRSTDII 


A3A1C 1031 


283-0059-02 






CAP ,F XD,C E R DI:1U F ,20%,50V 


04222 


SR305C105MAATRSTDII 


A3A1C 1032 


290-0536-04 






CAP,FXD,ELCTLT:10UF,20%,25V 


24165 


199D106X0025CA1 


A3A1C 1033 


290-0536-04 






CAP,FXD,ELCTLT:10UF,20%,25V 


24165 


199D106X0025CA1 


A3A1C 1034 


283-0177-00 






CAP, FXD,CER DI:1UF, +80-20%, 25V 


04222 


SR305E105ZAA 


A3A1C 1035 


283-0177-00 






CAP, FXD,CER DI:1UF, +80-20%, 25V 


04222 


SR305E105ZAA 


A3A1C 1036 


283-0177-00 






CAP, FXD,CER DI:1UF, +80-20%, 25V 


04222 


SR305E105ZAA 


A3A1C 1037 


290-0973-01 






CAP,FXD,ELCTLT:100UF,20%,25VDC AL 


1W344 


SME35VB101M8X11FT 


A3A1C 1038 


283-0177-00 






CAP, FXD,CER DI:1UF, +80-20%, 25V 


04222 


SR305E105ZAA 


A3A1C 2010 


290-0973-01 






CAP,FXD,ELCTLT:100UF,20%,25VDC AL 


1W344 


SME35VB101M8X11FT 



1502B MTDR Service Manual 



8-25 



Replaceable Electrical Parts 



Replaceable Parts List (Cont.) 



Assy 

Number 


Tektronix 
Part Number 


Serial No. 
Effective 


Serial No. 
Discont’d 


Qty Name & Description 


Mfr. 

Code 


Mfr. Part Number 


A3A1 


670-9286-XX 






CIRCUIT BD ASSY:POWER SUPPLY (Con’t) 






A3A1C 2011 


290-0517-00 






CAP,FXD f ELCTLT:6.8UF ,20%,35V 


24165 


199D685X0035DA1 


A3A1C 2012 


290-0973-01 






CAP,FXD f ELCTLT:100UF ,20%,25VDC AL 


1W344 


SME35VB101M8X11FT 


A3A1C 2013 


283-0198-00 


R020399 




CAP ,FXD,C E R DI:0.22U F,20%,50V 


04222 


SR305C224MAA 


A3A1C2020 


283-0051-00 






CAP ,FXD f C E R Dl :0.0033U F f 5%,100V 


04222 


SR301A332J AA 


A3A1C2021 


290-0745-02 






CAP, FXD,ELCTLT:22UF, +50-10%, 25V ,AL 


55680 


UVX2A220MPA 


A3A1C2022 


283-0010-00 






CAP, FXD.CER DI:0.05UF, +80-20%, 50V 


04222 


SR305E503ZAA 


A3A1C2023 


283-0220-02 






CAP,FXD,CER DI:0.01U F ,20%,50V 


04222 


AR205C 103M AATRSTDII 


A3A1C2024 


281-0925-01 






CAP,FXD,CER DI:0.22UF,20%,50V 


31433 


C 114C 224M5Y5CA 


A3A1C2025 


290-0846-00 






CAP, FXD,ELCTLT:47UF, +75-20%, 35V AL 


0J9R5 


CEUSM1J 470 


A3A1C2030 


281-0925-01 






CAP,FXD,CER DI:0.22UF,20%,50V 


31433 


C 114C 224M5Y5CA 


A3A1C2031 


283-0059-02 






CAP,FXD,CER DI:1UF,20%,50V 


04222 


S R 305C 105M AATRSTDII 


A3A1C R 1010 


152-0406-00 






DIODE, RECT:BRIDGE, 250V, 3A.1.2VF 


14936 


GBPC604 


A3A1C R 1011 


152-0322-00 






DIODE DVC ,D 1 :S C H OTTKY ,5 l,15V,1.2P F 


50434 


5082-2672 


A3A1C R 1030 


152-0582-00 






DIODE, RECT:SCHTKY, 20V, 3A,.475VF,80A 


04713 


1N5820 


A3A1C R 1031 


152-0582-00 






DIODE, RECT:SCHTKY, 20V, 3A,.475VF,80A 


04713 


1N5820 


A3A1C R 1032 


152-0581-00 






DIODE, RECT:SCHTKY, 20V, 1A,.450VF,25A 


14936 


SB120-5 


A3A1C R 1033 


152-0581-00 






DIODE, RECT:SCHTKY, 20V, 1A,.450VF,25A 


14936 


SB120-5 


A3A1C R 1034 


152-0779-00 






DIODE, RECT:FAST RC VRY;BR IDG E , 200V 


80009 


152-0779-00 


A3A1CR2010 


152-0601-00 






DIODE, RECT:ULTRAFAST;150V,25NS,35A 


04713 


M U R 115 


A3A1CR2011 


152-1165-00 






DIODE, RECT:600V,4A,50NS 


04713 


MUR460RL 


A3A1C R 2012 


152-0582-00 






DIODE, RECT:SCHTKY, 20V, 3A,.475VF,80A 


04713 


1N5820 


A3A1C R 2013 


152-0322-00 






DIODE DVC, D l:S CH OTTKY, SI, 15V, 1.2PF 


50434 


5082-2672 


A3A1CR2014 


152-0322-00 






DIODE DVC, D l:S CH OTTKY, SI, 15V, 1.2PF 


50434 


5082-2672 


A3A1C R 2015 


152-0601-00 


R010100 


R010140 


DIODE, RECT:ULTRAFAST;150V,25NS,35A 


04713 


M U R 115 




152-0836-00 


R010141 




DIODE DVC,DI:RECT,SI,1A,40V 1N5819 


80009 


152-0836-00 


A3A1C R 2016 


152-0141-02 






DIODE,SIG:ULTRA FAST ;40V,150M A,4N S ,2P F 


14433 


IN 4152 


A3A1CR2020 


152-0322-00 






DIODE DVC, D l:S CH OTTKY, SI, 15V, 1.2PF 


50434 


5082-2672 


A3A1CR2021 


152-0601-00 






DIODE, RECT:ULTRAFAST;150V,25NS,35A 


04713 


M U R 115 


A3A1CR2030 


152-0333-00 






DIODE DVC,DI:SW,SI,55V,200MA 


12969 


NDP261 


A3A1CR2031 


152-0333-00 






DIODE DVC,DI:SW,SI,55V,200MA 


12969 


NDP261 



8-26 



1502B MTDR Service Manual 



Replaceable Electrical Parts 



Replaceable Parts List (Cont.) 



Assy 

Number 


Tektronix 
Part Number 


Serial No. 
Effective 


Serial No. 
Discont’d 


Qty Name & Description 


Mfr. 

Code 


Mfr. Part Number 


A3A1 


670-9286-XX 






CIRCUIT BD ASSY:POWER SUPPLY (Con’t) 






A3A1J 1010 


131-4177-00 






C0NN,HDR:PCB,MALE,STR,1X 31,0.15 CTR 


80009 


131-4177-00 


A3A1J 1030 


131-3445-00 






CONN,HDR:PCB,MALE,RTANG,2 X 7,0.1 CTR 


80009 


131-3445-00 


A3A1J 2010 


131-1857-00 






CONN, HDR:PCB, MALE, STR,1 X 36,0.1 CTR 


58050 


082-3644-SS10 


A3A1L1010 


108-1230-00 






COIL,RF:FIXED,100UH,5% POT CORE 


54937 


500-3990 


A3A1L2020 


108-1230-00 






CO IL,R F :F IXE D,100U H ,5% POT CORE 


54937 


500-3990 


A3A1Q1010 


151-1176-00 






XSTR,PWR:MOS,P-CH;100V,1.0A,0.6 0HM 


04713 


IRFD9120 


A3A1Q1011 


151-1176-00 






XSTR,PWR:MOS,P-CH;100V,1.0A,0.6 OHM 


04713 


IRFD9120 


A3A1Q1012 


151-0736-00 






XSTR :N P N,SI,TO-92 2N4401 


04713 


2N4401 


A3A1Q2010 


151-0736-00 






XSTR:NPN,SI,TO-92 2N4401 


04713 


2N4401 


A3A1Q2011 


151-1176-00 






XSTR, PWR:MOS,P-CH;100V,1.0A, 0.6 OHM 


04713 


IRFD9120 


A3A1Q2012 


151-1176-00 






XSTR, PWR:MOS,P-CH;100V,1.0A, 0.6 OHM 


04713 


IRFD9120 


A3A1Q2020 


151-0188-00 






XSTR, SIG:BIPOLAR,PNP;40V,200MA,250MHZ, AMP 


03508 


X39H3162 


A3A1Q2021 


151-0424-00 






XSTR :N P N,SI,TO-92 MPS2369A 


04713 


MPS2369A 


A3A1Q2022 


151-1136-00 






XSTR, PWR:MOS,N-CH;100V,14A, 0.16 OHM 


04713 


MTP12N10E 


A3A1Q2030 


151-1063-00 






XSTR, PWR:MOS,N-CH;60V,0.8A, 0.8 OHM 


04713 


IRFD113 


A3A1Q2031 


151-1063-00 






XSTR, PWR:MOS,N-CH;60V,0.8A, 0.8 OHM 


04713 


IRFD113 


A3A1R 1010 


308-0839-00 






RES,FXD:0.1 OHM, 5%, 1.0W Ml 


56637 


BW10.1OHM 


A3A1R1011 


322-3193-00 






RE S,FXD:M ETAL FILM :1K OHM,1%,0.2W 


57668 


CRB20FXE 1K00 


A3A1R1012 


322-3222-00 






RE S,FXD:M ETAL FILM :2K OHM,1%,0.2W 


57668 


CRB20FXE 2K00 


A3A1R1013 


322-3309-00 






RES,FXD,FILM:16.2K OHM,1%,0.2W 


91637 


CCF50-2-G16201FT 


A3A1R 1014 


322-3243-00 






RE S,FXD:M ETAL FILM:3.32K OHM,1%,0.2W 


91637 


CCF50-1-G3200F 


A3A1R 1015 


322-3231-00 






RES,FXD,FILM:2.49K OHM,1%,0.2W 


57668 


CRB20FXE 2K49 


A3A1R 1016 


321-0301-00 


R010100 


R010140 


RES,FXD,FILM:13.3K OHM,1%,0.125W 


80009 


321-0301-00 




322-3303-00 


R010141 




RES,FXD,FILM:14K OHM ,1%,0.2W 


57668 


CRB20FXE 14K0 


A3A1R 1017 


322-3243-00 






RE S,FXD:M ETAL FILM:3.32K OHM,1%,0.2W 


91637 


CCF50-1-G3200F 


A3A1R 1018 


322-3318-00 






RE S,FXD:M ETAL FILM:20K OHM,1%,0.2W 


57668 


CRB20FXE 20K0 


A3A1R 1020 


321-0133-00 


R010100 


R020398 


RES,FXD,FILM:237 OHM,1%,0.125W 


80009 


321-0133-00 




322-3189-00 


R020399 




RES,FXD,FILM :909 OHM ,1%,0.2W 


57668 


CRB20FXE 909E 



1502B MTDR Service Manual 



8-27 



Replaceable Electrical Parts 



Replaceable Parts List (Cont.) 



Assy 

Number 


Tektronix 
Part Number 


Serial No. 
Effective 


Serial No. 
Discont’d 


Qty Name & Description 


Mfr. 

Code 


Mfr. Part Number 


A3A1 


670-9286-XX 






CIRCUIT BD ASSY:POWER SUPPLY (Con’t) 






A3A1R1021 


321-0296-00 


R010100 


R020398 


RES,FXD,FILM :11.8K O H M ,1%,0.125W 


80009 


321-0296-00 




322-3293-00 


R020399 




RES,FXD,FILM:11K OHM ,1%,0.2W 


57668 


CRB20FXE 11K0 


A3A1R 1022 


321-0197-00 


R010100 


R020398 


RES f FXD f FILM:1.10K OH M ,1%,0.125W 


80009 


321-0197-00 




322-3191-00 


R020399 




RES,FXD,FILM:953 OHM ,1%,0.2W 


57668 


CRB20FXE 953E 


A3A1R 1023 


322-3235-00 






RE S,FXD:M ETAL FILM:2.74K OHM,1%,0.2W 


57668 


CRB20FXE 2K74 


A3A1R 1024 


322-3231-00 






RES,FXD,FILM:2.49K OHM,1%,0.2W 


57668 


CRB20FXE 2K49 


A3A1R 1025 


321-0302-00 






RES,FXD,FILM:13.7K OH M ,1%,0.125W 


57668 


CRB20FXE 13K7 


A3A1R 1026 


322-3193-00 






RES,FXD:M ETAL FILM :1K OHM,1%,0.2W 


57668 


CRB20FXE 1K00 


A3A1R 1030 


317-0027-00 






RES,FXD,CMPSN:2.7 OHM ,5%,0.125W 


01121 


BB27G5 


A3A1R2010 


321-0245-00 


R010100 


R010140 


RES,FXD,FILM:3.48K OH M ,1%,0.125W 


80009 


321-0245-00 




322-3257-00 


R010141 




RES,FXD,FILM:4.64K OHM,1%,0.2W 


91637 


CCF50-2-G46400FT 


A3A1R2011 


322-3300-02 






RES,FXD,FILM:13K OHM ,1%,0.2W 


57668 


CRB20 DYE 13K0 


A3A1R2012 


321-0001-00 


R010100 


R010140 


RES,FXD,FILM:10 OH M ,1%,0.125W 


80009 


321-0001-00 




308-0739-00 


R010141 




RES,FXD,WW:4 OHM,l%,3W 


01686 


T2B-79-4 


A3A1R2013 


322-3385-00 






RES,FXD:M ETAL FILM:100K OHM,1%,0.2W 


57668 


CRB20FXE 100K 


A3A1R2014 


322-3357-00 






RES,FXD f F ILM :51.1K OHM,1%,0.2W 


57668 


CRB20FXE 51K1 


A3A1R2015 


322-3289-00 






RES,FXD:M ETAL FILM:10K OHM,1%,0.2W 


57668 


CRB20FXE 10K0 


A3A1R2016 


322-3097-00 






RES,FXD:M ETAL FILM:100 OHM,1%,0.2W 


57668 


CRB20FXE 100E 


A3A1R2017 


322-3385-00 






RE S,FXD:M ETAL FILM:100K OHM,1%,0.2W 


57668 


CRB20FXE 100K 


A3A1R2018 


322-3385-00 






RE S,FXD:M ETAL FILM:100K OHM,1%,0.2W 


57668 


CRB20FXE 100K 


A3A1R2020 


321-0253-00 






RES,FXD,FILM:4.22K OH M ,1%,0.125W 


19701 


5033ED4K 220F 


A3A1R2021 


322-3222-00 






RE S,FXD:M ETAL FILM :2K OHM,1%,0.2W 


57668 


CRB20FXE 2K00 


A3A1R2022 


322-3193-00 






RE S,FXD:M ETAL FILM :1K OHM,1%,0.2W 


57668 


CRB20FXE 1K00 


A3A1R2023 


322-3261-00 






RES,FXD,FILM:5.11K OHM,1%,0.2W 


91637 


CCF50G5111FT 


A3A1R2024 


322-3239-00 






RES,FXD,FILM:3.01K OHM,1%,0.2W 


57668 


CRB20FXE 3K01 


A3A1R2025 


322-3239-00 






RES,FXD,FILM:3.01K OHM,1%,0.2W 


57668 


CRB20FXE 3K01 


A3A1R2026 


322-3289-00 






RE S,FXD:M ETAL FILM:10K OHM,1%,0.2W 


57668 


CRB20FXE 10K0 


A3A1R2027 


308-0839-00 






RES,FXD:0.1 OHM, 5%, 1.0W Ml 


56637 


BW1 0.1 OHM 


A3A1R2030 


322-3326-00 






RES,FXD,FILM:24.3K OHM,1%,0.2W 


91637 


CCF50-2F24301F 


A3A1R2031 


317-0027-00 






RES,FXD,CMPSN:2.7 OHM ,5%,0.125W 


01121 


BB27G5 


A3A1R2032 


308-0767-00 






RES,FXD:1.10HM,5%,1W Ml 


75042 


S P-20- 1.1 OHM -5% 



8-28 



1502B MTDR Service Manual 



Replaceable Electrical Parts 



Replaceable Parts List (Cont.) 



Assy 

Number 


Tektronix 
Part Number 


Serial No. 
Effective 


Serial No. 
Discont’d 


Qty Name & Description 


Mfr. 

Code 


Mfr. Part Number 


A3A1 


670-9286-XX 






CIRCUIT BD ASSY:POWER SUPPLY (Con’t) 






A3A1S 2010 


260-2370-00 






SWITCH, TOGGLE:SPDT,3A,250VAC 


80009 


260-2370-00 


A3A1T1030 


120-1608-00 






XFMR,PWR:SW,40KHZ,IN 16.2V, OUT +/-15V 34MA 


0JR03 


120-1608-00 


A3A1T1031 


120-0487-00 






XFMR,TOROID:5TURNS,BI F ILAR ,3T2 


0JR03 


120-0487-00 


A3A1TP 1010 


214-0579-02 


B010100 


B037261 


TERM, TEST POINT:0.052 ID, 0.169 H, 0.465 L 


10392 


7-16150-8 


A3A1TP 1020 


214-0579-02 


B010100 


B037261 


TERM, TEST POINT:0.052 ID, 0.169 H, 0.465 L 


10392 


7-16150-8 


A3A1TP 2010 


214-0579-02 


B010100 


B037261 


TERM, TEST POINT:0.052 ID, 0.169 H, 0.465 L 


10392 


7-16150-8 


A3A1TP2030 


214-0579-02 


B010100 


B037261 


TERM, TEST POINT:0.052 ID, 0.169 H, 0.465 L 


10392 


7-16150-8 


A3A1U 1010 


156-0933-00 






1C, LINEAR:REGULATOR, PULSE WIDTH 


34333 


SG3524N 


A3A1U 1011 


156-1173-00 






1C, LINEAR:BIPOLAR, VOLT REF;POS, 2.5V, 1.0% 


04713 


MC1403U 


A3A1U 1020 


156-1225-00 






IC,LINEAR:BIPO LAR,CO M P AR ATO R ;DU AL 


04713 


LM393N 


A3A1U 1021 


156-1225-00 






IC,LINEAR:BIPO LAR,CO M P AR ATO R ;DU AL 


04713 


LM393N 


A3A1U 1022 


156-1173-00 






1C, LINEAR:BIPOLAR, VOLT REF;POS, 2.5V, 1.0% 


04713 


MC1403U 


A3A1U 1023 


156-0933-00 






1C, LINEAR:REGULATOR, PULSE WIDTH 


34333 


SG3524N 


A3A1U 1024 


156-0366-00 






IC,DIGITAL:CMOS,FLIP FLOP ;DU AL D-TYPE 


04713 


MC14013BCP 


A3A1U 2010 


156-1161-00 






1C, LIN EAR BIPOLAR, VOLT REG ;POS,ADJ 


04713 


LM317T 


A3A1U2030 


156-0494-00 






IC,DIGITAL:CMOS,BUFFER/DRIVER;HEX INV 


04713 


MC14049UBCP 


A3A1VR 1012 


152-0217-00 


R010141 




DIODE,ZENER:8.2V,5%,0.4W 


14552 


TD3810979 



1502B MTDR Service Manual 



8-29 



Replaceable Electrical Parts 



Replaceable Parts List (Cont.) 



Assy 

Number 


Tektronix 
Part Number 


Serial No. 
Effective 


Serial No. 
Discont’d 


Qty Name & Description 


Mfr. 

Code 


Mfr. Part Number 


A4 


670-9291 -XX 






CKT BD ASSY:S/R DRIVER SAMPLER 






A4C1010 


281-0775-00 






CAP ,FXD,C E R DI:0.1U F,20% I 50V 


04222 


SA105E104MAA 


A4C1011 


281-0775-00 






CAP ,FXD,C E R DhO.lLI F,20% I 50V 


04222 


SA105E104MAA 


A4C1020 


290-0723-00 






CAP,FXD,ELCTLT:150UF,20%,6V 


24165 


196D157X0006PE3 


A4C1030 


281-0775-00 






CAP ,FXD,C E R DhO.lLI F ( 20%,50V 


04222 


SA105E104MAA 


A4C1040 


281-0775-00 






CAP ,FXD,C E R DLO.IU F,20% I 50V 


04222 


SA105E104MAA 


A4C1041 


290-0804-01 






CAP,FXD ; ELCTLT:10U F ,20%,25V AL 


0H1N5 


C E US M IE 100T12 


A4C1050 


281-0765-00 






C AP ,FXD,C E R D 1 :100P F ,5% I 100V 


04222 


SA102A101J AA 


A4C1060 


281-0775-00 






C AP ,FXD,C E R D 1 :0.1U F ,20% f 50V 


04222 


SA105E104MAA 


A4C1061 


281-0775-00 






C AP ,FXD,C E R DI:0.1U F ,20%,50V 


04222 


SA105E104MAA 


A4C1070 


281-0775-00 






CAP,FXD,CER DI:0.1U F ,20%,50V 


04222 


SA105E104MAA 


A4C1071 


281-0775-00 






C AP ,FXD,C E R DI:0.1U F ,20%,50V 


04222 


SA105E104MAA 


A4C2010 


290-0536-04 






CAP,FXD,ELCTLT:10U F ,20%,25V 


24165 


199D106X0025CA1 


A4C2011 


283-5002-00 


B021135 


B036426 


C AP ,F XD,C E R D 1 :1000P F l 10%,50V 


04222 


W1206C 102K3B04 




283-0359-01 


B036427 




C AP ,FXD,C E R D 1 :1000P F ,5%,200V 


31433 


C322C102J 2G5CA 


A4C2012 


283-5002-00 


B021135 


B036426 


C AP ,F XD,C E R D 1 :1000P F ,10% f 50V 


04222 


W1206C 102K3B04 




283-0359-01 


B036427 




C AP ,FXD,C E R D 1 :1000P F ,5%,200V 


31433 


C322C102J 2G5CA 


A4C2020 


290-0523-00 






CAP,FXD,ELCTLT:2.2UF ,20%,20V 


24165 


196D225X0020HA1 


A4C2021 


290-0523-00 






CAP,FXD ; ELCTLT:2.2UF ,20%,20V 


24165 


196D225X0020HA1 


A4C2022 


290-0523-00 






CAP,FXD,ELCTLT:2.2UF,20%,20V 


24165 


196D225X0020HA1 


A4C2023 


290-0523-00 






CAP,FXD,ELCTLT:2.2UF ,20%,20V 


24165 


196D225X0020HA1 


A4C2024 


290-0523-00 






CAP,FXD,ELCTLT:2.2UF,20%,20V 


24165 


196D225X0020HA1 


A4C2025 


283-5002-00 


B021135 


B036426 


C AP ,F XD,C E R DhlOOOP F ,10%,50V 


04222 


W1206C 102K3B04 




283-0359-01 


B036427 




CAP ,FXD,C E R DL1000P F ,5%,200V 


31433 


C322C102J 2G5CA 


A4C2026 


283-5002-00 


B021135 


B036426 


CAP ,F XD,C E R DhlOOOP F ,10%,50V 


04222 


W1206C 102K3B04 




283-0359-01 


B036427 




CAP ,FXD,C E R DhlOOOP F ,5%,200V 


31433 


C322C102J 2G5CA 


A4C2030 


281-0861-00 






CAP ,FXD,C E R DI:270P F ,5%,50V 


04222 


SA101A271J AA 


A4C2031 


283-0193-00 






CAP ,FXD f C E R DI:510P F I 2%,100V 


04222 


SR201A511GAA 


A4C2040 


281-0775-00 






CAP ,FXD,C E R DI:0.1U F,20%,50V 


04222 


SA105E104MAA 


A4C2041 


281-0775-00 






CAP,FXD,CER DI:0.1U F,20%,50V 


04222 


SA105E104MAA 


A4C2042 


281-0861-00 






CAP ,FXD,C E R DI:270P F ,5%,50V 


04222 


SA101A271J AA 


A4C2050 


281-0775-00 






CAP ,FXD,C E R DhO.lLI F,20%,50V 


04222 


SA105E104MAA 


A4C2051 


290-0522-01 






CAP,FXD,ELCTLT:1UF ,20%,50V 


31433 


T355B105M050AS 



8-30 1 502B MTDR Service Manual 



Replaceable Electrical Parts 



Replaceable Parts List (Cont.) 



Assy 

Number 


Tektronix 
Part Number 


Serial No. 
Effective 


Serial No. 
Discont’d 


Qty Name & Description 


Mfr. 

Code 


Mfr. Part Number 


A4 


670-9291 -XX 






CKT BD ASSY:S/R DRIVER SAMPLER (Con’t) 






A4C2052 


281-0775-00 






CAP ,FXD,C E R DLO.IU F,20% f 50V 


04222 


SA105E104MAA 


A4C2053 


285-0627-00 






CAP,FXD,PLASTIC:0.0033UF,5%,100V 


01002 


61F10AC332 


A4C2072 


290-0782-01 






CAP,FXD,ELCTLT:4.7UF ,20%,35VDC AL 


55680 


UVX1V4R7MAA1TD 


A4C2080 


290-0844-00 






CAP, FXD,ELCTLT:100UF, +75-20%, 35WVDC AL 


0J9R5 


CEUSM1V101 


A4C2081 


290-0844-00 






CAP, FXD,ELCTLT:100UF, +75-20%, 35WVDCAL 


0J9R5 


CEUSM1V101 


A4C2082 


283-5002-00 


B021135 


B036426 


CAP ,FXD,C E R DhlOOOP F ,10%,50V 


04222 


W1206C 102K3B04 




283-0359-01 


B036427 




CAP,FXD,CER DhlOOOP F ,5%,200V 


31433 


C322C102J 2G5CA 


A4C2083 


283-5002-00 


B021135 


B036426 


CAP ,FXD,C E R DhlOOOP F ,10%,50V 


04222 


W1206C 102K3B04 




283-0359-01 


B036427 




CAP,FXD,CER DhlOOOP F ,5%,200V 


31433 


C322C102J 2G5CA 


A4C3010 


290-0844-00 






CAP, FXD,ELCTLT:100UF, +75-20%, 35WVDCAL 


0J9R5 


CEUSM1V101 


A4C3011 


290-0844-00 






CAP, FXD,ELCTLT:100UF, +75-20%, 35WVDCAL 


0J9R5 


CEUSM1V101 


A4C3020 


281-0775-00 






CAP,FXD,CER DI:0.1UF,20%,50V 


04222 


SA105E104MAA 


A4C3030 


283-0193-00 






CAP,FXD,CER DI:510PF,2%,100V 


04222 


SR201A511GAA 


A4C3060 


281-0775-00 






CAP,FXD,CER DI:0.1UF,20%,50V 


04222 


SA105E104MAA 


A4C3061 


281-0775-00 






CAP,FXD,CER DI:0.1UF,20%,50V 


04222 


SA105E104MAA 


A4C3062 


290-0844-00 






CAP, FXD,ELCTLT:100UF, +75-20%, 35WVDCAL 


0J9R5 


CEUSM1V101 


A4C3063 


290-0844-00 






CAP, FXD,ELCTLT:100UF, +75-20%, 35WVDCAL 


0J9R5 


CEUSM1V101 


A4C3064 


283-5002-00 


B021135 


B036426 


CAP ,FXD,C E R DhlOOOP F ,10%,50V 


04222 


W1206C 102K3B04 




283-0359-01 


B036427 




CAP ,FXD,C E R DhlOOOP F ,5%,200V 


31433 


C322C102J 2G5CA 


A4C3065 


283-5002-00 


B021135 


B036426 


CAP ,F XD,C E R DL1000P F ,10%,50V 


04222 


W1206C 102K3B04 




283-0359-01 


B036427 




CAP ,FXD,C E R DhlOOOP F ,5%,200V 


31433 


C322C102J 2G5CA 


A4C3070 


281-0775-00 






CAP ,FXD,C E R DI:0.1UF,20%,50V 


04222 


SA105E104MAA 


A4C3080 


281-0775-00 






CAP ,FXD,C E R DI:0.1UF,20%,50V 


04222 


SA105E104MAA 


A4CR1030 


152-0322-00 






DIODE DVC,DI:SCHOTTKY,SI,15V,1.2PF 


21847 


A2X600 


A4CR1031 


152-0141-02 






DIODE, SIG:ULTRAFAST;40V,150MA,4NS,2PF 


01295 


1N4152R 


A4CR1032 


152-0141-02 






DIODE, SIG:ULTRAFAST;40V,150MA,4NS,2PF 


01295 


1N4152R 


A4CR1040 


152-0322-00 






DIODE DVC,DI:SCHOTTKY,SI,15V,1.2PF 


21847 


A2X600 


A4CR2050 


152-0333-00 






DIODE DVC,DI:SW, SI, 55V, 200M A,DO- 351N461D 


03508 


DJ 2011 


A4CR2051 


152-0333-00 






DIODE DVC,DI:SW, SI, 55V, 200M A,DO- 351N461D 


03508 


DJ 2011 


A4CR2052 


152-0333-00 






DIODE DVC,DI:SW, SI, 55V, 200M A,DO- 351N461D 


03508 


DJ 2011 


A4CR3020 


152-0322-00 






DIODE DVC,DI:SCHOTTKY,SI,15V,1.2PF 


21847 


A2X600 


A4CR3021 


152-0322-00 






DIODE DVC,DI:SCHOTTKY,SI,15V,1.2PF 


21847 


A2X600 



1502B MTDR Service Manual 



8-31 



Replaceable Electrical Parts 



Replaceable Parts List (Cont.) 



Assy 

Number 


Tektronix 
Part Number 


Serial No. 
Effective 


Serial No. 
Discont’d 


Qty Name & Description 


Mfr. 

Code 


Mfr. Part Number 


A4 


670-9291 -XX 






CKT BD ASSY:S/R DRIVER SAMPLER (Con’t) 






A4J 3040 


131-3360-00 






C0NN,HDR:PCB,MALE,STR ( 2 X 10,0.1 CTR 


53387 


3592-6002 


A4L2080 


108-1032-00 






COIL, RF:FXD,225UH,20% TOROIDAL 


0JR03 


108-1032-00 


A4L2081 


108-1032-00 






COIL, RF:FXD,225UH, 20% TOROIDAL 


0JR03 


108-1032-00 


A4Q1030 


151-0190-00 






XSTR,SIG:BIPOLAR,NPN;40V,200MA,300MHZ,AMP 


01295 


SKA3703 


A4Q1060 


151-1103-00 






XSTR,SIG:DMOS,N-CH;ENH,30V,50MA,45 OHM 


17856 


DM 1140/S D210DE 


A4Q2030 


151-0271-00 






XSTR,SIG:BIPOLAR,PNP;15V,30MA,2.0GHZ,AMP 


01295 


SKA4504 


A4Q2040 


151-0190-00 






XSTR,SIG:BIPOLAR,NPN;40V,200MA,300MHZ,AMP 


01295 


SKA3703 


A4Q2050 


151-0188-00 






XSTR,SIG:BIPOLAR,PNP;40V,200MA,250MHZ,AMP 


03508 


X39H3162 


A4R1010 


315-0301-00 






RES,FXD,FILM :300 OHM ,5%,0.25W 


01121 


CB3015 


A4R1020 


315-0102-00 






RES,FXD,FILM:1K OHM ,5%,0.25W 


01121 


CB1025 


A4R1030 


315-0101-00 






RES,FXD,FILM:100 OHM ,5%,0.25W 


01121 


C B 1015 


A4R1031 


315-0103-00 






RES,FXD,FILM:10K OHM ,5%,0.25W 


01121 


CB1035 


A4R1040 


321-1249-00 






RES,FXD,FILM:3.88K OH M ,1%,0.125W 


01121 


ADVISE 


A4R1041 


321-0612-03 






RES, FXD,FILM:5000HM, 0.25, 0.125W 


19701 


5033RC500R0C 


A4R1042 


311-1921-00 






RES,VAR,NONWW:TRMR,2500HM,10%,0.5W 


02111 


63S251T602 


A4R1050 


322-3308-00 






RES,FXD,FILM:15.8K OHM,1%,0.2W 


57668 


CRB20FXE 15K8 


A4R1051 


322-3289-00 






RE S,FXD:M ETAL FILM:10K OHM,1%,0.2W 


57668 


CRB20FXE 10K0 


A4R1052 


315-0101-00 






RES,FXD,FILM:100 OHM ,5%,0.25W 


01121 


C B 1015 


A4R1053 


315-0101-00 






RES,FXD,FILM:100 OHM ,5%,0.25W 


01121 


C B 1015 


A4R1060 


322-3331-00 






RE S,FXD:M ETAL FILM:27.4K OHM,1%,0.2W 


57668 


CRB20FXE 27K4 


A4R1061 


322-3289-00 






RE S,FXD:M ETAL FILM:10K OHM,1%,0.2W 


57668 


CRB20FXE 10K0 


A4R1062 


322-3364-00 






RES,FXD,FILM:60.4K OHM,1%,0.2W 


57668 


CRB20FXE 60K4 


A4R1063 


322-3297-00 






RES,FXD,FILM:12.1K OHM,1%,0.2W 


57668 


CRB20FXE 12K1 


A4R1064 


322-3289-00 






RE S,FXD:M ETAL FILM:10K OHM,1%,0.2W 


57668 


CRB20FXE 10K0 


A4R1065 


322-3364-00 






RES,FXD,FILM:60.4K OHM,1%,0.2W 


57668 


CRB20FXE 60K4 


A4R1066 


322-3297-00 






RES,FXD,FILM:12.1K OHM,1%,0.2W 


57668 


CRB20FXE 12K1 


A4R1070 


322-3289-00 






RE S,FXD:M ETAL FILM:10K OHM,1%,0.2W 


57668 


CRB20FXE 10K0 


A4R1071 


315-0100-00 






RES,FXD,FILM:10 OH M ,5%,0.25W 


01121 


CB1005 


A4R1072 


315-0100-00 






RES,FXD,FILM:10 OH M ,5%,0.25W 


01121 


CB1005 



8-32 1 502B MTDR Service Manual 



Replaceable Electrical Parts 



Replaceable Parts List (Cont.) 



Assy 

Number 


Tektronix 
Part Number 


Serial No. 
Effective 


Serial No. 
Discont’d 


Qty Name & Description 


Mfr. 

Code 


Mfr. Part Number 


A4 


670-9291 -XX 






CKT BD ASSY:S/R DRIVER SAMPLER (Con’t) 






A4R2030 


315-0300-00 






RES,FXD,FILM:30 OH M ,5%,0.25W 


01121 


CB3005 


A4R2031 


315-0103-00 






RES,FXD,FILM:10K OHM ,5%,0.25W 


01121 


CB1035 


A4R2040 


315-0101-00 






RES,FXD,FILM:100 OHM ,5%,0.25W 


01121 


C B 1015 


A4R2041 


315-0511-00 






RES,FXD,FILM:510 OHM ,5%,0.25W 


01121 


CB5115 


A4R2042 


315-0101-00 






RES,FXD,FILM:100 OHM ,5%,0.25W 


01121 


C B 1015 


A4R2043 


315-0101-00 






RES,FXD,FILM:100 OHM ,5%,0.25W 


01121 


C B 1015 


A4R2045 


315-0121-00 






RES,FXD,FILM:120 OHM ,5%,0.25W 


01121 


C B 1215 


A4R2046 


315-0473-00 






RES,FXD,FILM:47K OHM ,5%,0.25W 


01121 


CB4735 


A4R2047 


315-0243-00 






RES,FXD,FILM:24K OHM ,5%,0.25W 


01121 


CB2435 


A4R2048 


315-0101-00 






RES,FXD,FILM:100 OHM ,5%,0.25W 


01121 


C B 1015 


A4R2049 


315-0562-00 






RES,FXD,FILM:5.6K OHM ,5%,0.25W 


01121 


CB5625 


A4R2050 


315-0101-00 






RES,FXD,FILM:100 OHM ,5%,0.25W 


01121 


C B 1015 


A4R2051 


315-0203-00 






RES,FXD,FILM:20K OHM ,5%,0.25W 


01121 


CB2035 


A4R2052 


315-0101-00 






RES,FXD,FILM:100 OHM ,5%,0.25W 


01121 


C B 1015 


A4R2053 


315-0562-00 






RES,FXD,FILM:5.6K OHM ,5%,0.25W 


01121 


CB5625 


A4R2054 


315-0752-00 






RES,FXD,FILM:7.5K OHM ,5%,0.25W 


01121 


CB7525 


A4R3020 


315-0100-00 






RES,FXD,FILM:10 OH M ,5%,0.25W 


01121 


CB1005 


A4R3021 


322-3344-00 






RES,FXD,FILM:37.4K OHM,1%,0.2W 


57668 


CRB20FXE 37K4 


A4R3032 


317-0027-00 






RES,FXD,CMPSN:2.7 OHM ,5%,0.125W 


01121 


BB27G5 


A4R3033 


317-0027-00 






RES,FXD,CMPSN:2.7 OHM ,5%,0.125W 


01121 


BB27G5 


A4R3040 


322-3268-00 






RES,FXD,FILM:6.04K OHM,1%,0.2W 


57668 


CRB20FXE 6K04 


A4R3050 


315-0100-00 






RES,FXD,FILM:10 OH M ,5%,0.25W 


01121 


CB1005 


A4R3051 


315-0100-00 






RES,FXD,FILM:10 OH M ,5%,0.25W 


01121 


CB1005 


A4R3061 


322-3396-00 






RES,FXD,FILM:130K OHM,1%,0.2W 


57668 


CRB20FXE 130K 


A4R3062 


321-0631-03 






RES,FXD ( FILM:12.5K OHM, 0.25%, 0.125W 


01121 


ADVISE 


A4R3070 


322-3389-00 






RES, FXD,FILM:110K OHM, 0.25%, 0.2W 


56845 


CCF-50-2-1103F 


A4R3071 


321-0645-00 






RES,FXD,FILM:100K OHM ,0.5%,0.125W 


19701 


5033RC1003D 


A4R3080 


321-0645-00 






RES,FXD,FILM:100K OHM ,0.5%,0.125W 


19701 


5033RC1003D 


A4T1020 


120-0582-00 






XFMR,TOROID:2 WINDINGS, 067-0572-00 


0JR03 


120-0582-00 



1502B MTDR Service Manual 



8-33 



Replaceable Electrical Parts 



Replaceable Parts List (Cont.) 



Assy 

Number 


Tektronix 
Part Number 


Serial No. 
Effective 


Serial No. 
Discont’d 


Qty Name & Description 


Mfr. 

Code 


Mfr. Part Number 


A4 


670-9291 -XX 






CKT BD ASSY:S/R DRIVER SAMPLER (Con’t) 






A4TP1020 


214-0579-00 


B010100 


B037261 


TERM, TEST POINT:0.052 ID, 0.169 H, 0.465 L 


80009 


214-0579-00 


A4TP1021 


214-0579-00 


B010100 


B037261 


TERM, TEST POINT:0.052 ID, 0.169 H, 0.465 L 


80009 


214-0579-00 


A4TP1030 


214-0579-00 


B010100 


B037261 


TERM, TEST POINT:0.052 ID, 0.169 H, 0.465 L 


80009 


214-0579-00 


A4TP1060 


214-0579-00 


B010100 


B037261 


TERM, TEST POINT:0.052 ID, 0.169 H, 0.465 L 


80009 


214-0579-00 


A4TP1080 


214-0579-00 


B010100 


B037261 


TERM, TEST POINT:0.052 ID, 0.169 H, 0.465 L 


80009 


214-0579-00 


A4TP1081 


214-0579-00 


B010100 


B037261 


TERM, TEST POINT:0.052 ID, 0.169 H, 0.465 L 


80009 


214-0579-00 


A4TP1082 


214-0579-00 


B010100 


B037261 


TERM, TEST POINT:0.052 ID, 0.169 H, 0.465 L 


80009 


214-0579-00 


A4TP1083 


214-0579-00 


B010100 


B037261 


TERM, TEST POINT:0.052 ID, 0.169 H, 0.465 L 


80009 


214-0579-00 


A4TP1084 


214-0579-00 


B010100 


B037261 


TERM, TEST POINT:0.052 ID, 0.169 H, 0.465 L 


80009 


214-0579-00 


A4TP2060 


214-0579-00 


B010100 


B037261 


TERM, TEST POINT:0.052 ID, 0.169 H, 0.465 L 


80009 


214-0579-00 


A4TP3020 


214-0579-00 


B010100 


B037261 


TERM, TEST POINT:0.052 ID, 0.169 H, 0.465 L 


80009 


214-0579-00 


A4U1010 


119-2369-01 






HYBRID:TDR FRONT END 


80009 


119-2369-01 


A4U1050 


156-0853-00 






IC,LINEAR:BIPO LAR ,0 P - AM P ;DU AL 


04713 


LM358N 


A4U1070 


156-0853-00 






IC,LINEAR:BIPO LAR ,0 P - AM P ;DU AL 


04713 


LM358N 


A4U2050 


156-1291-00 






IC,LINEAR:BIFET,OP-AMP;DUAL,LOW PWR 


01295 


TL062CP 


A4U2070 


156-1490-00 






IC,LINEAR:VOLTAGE REFERENCE 2-PIN 


1ES66 


ICL8069CCSQ2 


A4U3030 


156-2761-00 






1C, DIGITAL:HCMOS, MULTIVIBRATOR 


04713 


MC74HC221N 


A4U3070 


156-0853-00 






IC,LINEAR:BIPO LAR ,0 P -AM P ;DU AL 


04713 


LM358N 



8-34 1 502B MTDR Service Manual 



Replaceable Electrical Parts 



Replaceable Parts List (Cont.) 



Assy 


Tektronix 


Serial No. 


Serial No. 




Mfr. 




Number 


Part Number 


Effective 


Discont’d 


Qty Name & Description 


Code 


Mfr. Part Number 


A9 


670-6592-XX 






CIRCUIT BD ASSY:POWER FUSE JACK 
OPTION 03 ONLY 






A9F9100 


159-0266-00 






FUSE, CANISTER:3A, 125V, RADIAL LEAD 


75915 


273.003 



1502B MTDR Service Manual 



8-35 



Replaceable Electrical Parts 



Replaceable Parts List (Cont.) 


Assy 

Number 


Tektronix 
Part Number 


Serial No. 
Effective 


Serial No. 
Discont’d 


Qty Name & Description 


Mfr. 

Code 


Mfr. Part Number 










WIRE ASSEMBLIES 






W1010 


174-0955-00 






CA ASSY, RF;50 OHM COAX, 4.75 L 
(FROM A4U1010 TO FRONT PANELJ 100) 


80009 


174-0955-00 


W2010 


174-0950-00 






CA AS S Y,S P,ELEC:26,28 AWG ,11.0L 
(FROM OPTION PORT W201 TO A1A1J 2010) 


80009 


174-0950-00 


W2020 


174-0954-00 






WIRE ASSY:POWER SUP PLY, 4, 28 AWG 
(FROM A3A1J 2010 TO BANANA JACK W201) 


80009 


174-0954-00 


W5040 


174-0953-00 






CA ASSY,SP,ELEC:14,26 AWG ,6.125L 
(FROM A3A1J 1030 TO A1A1J 5040) 


80009 


174-0953-00 


W6010 


174-0951-00 






CA ASSY,SP,ELEC:20,28 AWG, 300V, RMS 
(FROM DISPLAY MODULE A5 AND A2A1J 1020TO 
A1A1J 6010) 


80009 


174-0951-00 


W9010 


174-0952-00 






CA ASSY,SP,ELEC:20,28 AWG, 6.125 L, RIBBON 
(FROM A4J 3040 TO A1A1J 9010) 


80009 


174-0952-00 


J 101 


174-0957-00 


B010100 


B037303 


CA ASSY,PWR:2 STRAND W/CONN 
(FROM A3T210TO POWER SUPPLY) 


80009 


174-0957-00 




198-5460-00 


R010100 


R020421 


WIRE SET,ELEC:POWER SUPPLY MODULE 


80009 


198-5460-00 




198-5460-01 


R020422 




WIRE SET,ELEC:POWER SUPPLY MODULE 


80009 


198-5460-01 



8-36 



1502B MTDR Service Manual 



Diagrams 



General Information 

Assembly Numbers 



Grid Coordinates 



Electrical Parts Locator 



Schematic Symbols 



Component Values 



Each assembly in the instrument is assigned an assembly number (e.g., Al). The 
assembly number appears in the title block of the schematic diagram, in the title for 
the circuit board component location illustration, and in the lookup table for the 
schematic diagram component locator. The replacable parts list is arranged by 
assemblies in numerical sequence: the components are listed by component 
number. 



The schematic diagram and circuit board component location illistration have grids. 
A lookup table with the grid coordinates is provided for to help you locate the 
component. 



The component locator lookup table provides an alphanumeric listing of all cirucit 
numbers for the circuit boards in the instrument. Corresponding to each circuit 
number is a schematic page reference, the locator for that schematic page, and the 
locator for the circuit board. 

The locator lists are given for each circuit board, ordered by that board’s assembly 
number: 

An example entry is as follows: 





Schematic 


Schematic 


Board 




Page 


Locator 


Locator 




i 


i 


i 


Cl 0306 


2B 


D8 


Cl 



Read: Capacitor C10306 is found on schematic 2B in grid D8. Its physical location 
is grid Cl on the circuit board. 

A locator list and circuit board grid are also given on each circuit board illustration. 



Graphic symbols and class designation letters are based on ANSI standards. 

Logic symbology reflects the actual part function, not the logic function performed. 
Therefore, logic symbols should reflect manufacturer’s data. 



Electrical components shown on the diagrams are in the following units: 
Resitstors = Ohm (O) 



1502B MTDR Service Manual 



9-1 




Diagrams 



Component Number 



Capacitors = Farad (F) 

Inductors = Henry (H) 

All capacitors and inductors indicatate their units; resistors only indicate the 
appropriate scale factor. 

Scale factors are given by the following standard: 



M 


mega 


10 6 


k 


kilo 


10 3 


m 


milli 


10-3 


u 


micro (p,) 


10 -6 


n 


nano 


10- 9 


P 


pico 


10- 12 



A numbering method is used to identify assemblies, subassemblies, and parts. An 
example of this numbering method and typical expansions is as follows: 



R1234 

i 

Circuit 
Number 

Read: resistor 1234 of subassembly 2 of assy 23. 



A23A2R1234 = 



A23 

i 

Assembly 

Number 



A2 

i 

Subassembly 

Number 



Only circuit numbers appear on the schematics, circuit board illustrations, and 
electrical parts locator lists. Each schematic and illustration is marked with its 
assembly number. Assembly numbers are also marked on the mechanical exploded 
view located in the replaceable mechanical parts list. A component number is 
obtained by adding the assembly number prefix to the circuit number. The 
component number may then be used to reference a part in the replaceable electrical 
parts list. 



9-2 



1502B MTDR Service Manual 



Diagrams 



Refer to Internal 




part number reference number 

number 



Figure 9-1 : Special Schematic Symbols 



1502B MTDR Service Manual 



9-3 



Diagrams 



A1 - MAIN 



CIRCUIT 


SCHEM 


LOCATION 


CIRCUIT 


SCHEM 


LOCATION 


CIRCUIT 


SCHEM 


LOCATION 


NUMBER 


PAGE 


SCHEM 


BRD 


NUMBER 


PAGE 


SCHEM 


BRD 


NUMBER 


PAGE 


SCHEM 


BRD 








BT1010 


2 


G2 


A1 


C3020 


2 


B4 


B3 


C7030 


8B 


D2 


C7 










C3021 


8A 


E4 


B3 


C7040 


6 


D2 


D7 


C1010 


2 


G4 


A1 


C3022 


8A 


E4 


B3 


C7041 


6 


G1 


D7 


C1011 


2 


A4 


A1 


C3023 


8A 


D3 


B3 


C7042 


6 


G1 


D7 


Cl 020 


2 


B4 


B1 


C3030 


8B 


A1 


C3 


C7043 


1 


F2 


D7 


Cl 021 


2 


D1 


B1 


C3040 


8B 


A2 


D3 


C8010 


8A 


F2 


A8 


Cl 022 


2 


E2 


B1 


















Cl 023 


2 


El 


B1 


C3041 


6 


C3 


D3 


C8020 


8A 


D2 


B8 










C3042 


6 


G2 


D3 


C8021 


8A 


C2 


B8 


Cl 024 


2 


FI 


B1 


C3043 


6 


B2 


D3 


C8022 


8A 


A1 


B8 


Cl 030 


2 


Cl 


Cl 


C3044 


6 


B2 


D3 


C8023 


8B 


G4 


B8 


Cl 031 


2 


A4 


Cl 


C3045 


6 


HI 


D3 


C8024 


8B 


E2 


B8 


Cl 032 


2 


FI 


Cl 


C3046 


6 


HI 


D3 


C8040 


6 


C2 


D8 


Cl 040 


3 


B4 


D1 


















Cl 041 


3 


B4 


D1 


C3047 


8B 


A2 


D3 


C9010 


8A 


G2 


A9 










C3048 


8B 


A1 


D3 


C9011 


8A 


FI 


A9 


Cl 042 


1 


G2 


D1 


C4020 


8B 


D3 


B4 


C9020 


8A 


D1 


B9 


Cl 043 


2 


A4 


D1 


C4021 


8A 


E3 


B4 


C9021 


8A 


Cl 


B9 


C2010 


5 


G3 


A2 


C4022 


8A 


G3 


B4 


C9022 


8A 


D2 


B9 


C2011 


5 


G2 


A2 


C4030 


8B 


B1 


C4 


C9023 


8A 


C2 


B9 


C2012 


2 


B4 


A2 


















C2013 


4 


A4 


A2 


C4040 


8B 


C2 


D4 


C9024 


8A 


Cl 


B9 










C4041 


1 


F2 


D4 


C9025 


8B 


G4 


B9 


C2014 


4 


B4 


A2 


C5010 


8B 


E3 


A5 


C9030 


5 


B1 


C9 


C2015 


5 


F3 


A2 


C5020 


8B 


D4 


B5 


C9031 


5 


Cl 


C9 


C2016 


5 


F2 


A2 


C5021 


8B 


B4 


B5 


C9032 


5 


B1 


C9 


C2020 


3 


B4 


B2 


C5022 


8B 


B3 


B5 


C9033 


5 


B2 


C9 


C2021 


7 


B4 


B2 


















C2030 


7 


C4 


C2 


C5023 


8B 


F2 


B5 


C9034 


5 


B1 


C9 










C5024 


8B 


G3 


B5 


C9035 


5 


Cl 


C9 


C2031 


7 


B2 


C2 


C5025 


8B 


G3 


B5 










C2032 


7 


C4 


C2 


C5030 


8B 


E3 


C5 


CR1020 


2 


F2 


B1 


C2033 


7 


C4 


C2 


C5031 


8B 


Cl 


C5 


CR1021 


2 


F2 


B1 


C2034 


7 


D4 


C2 


C5032 


8B 


C2 


C5 


CR1022 


2 


FI 


B1 


C2035 


7 


D4 


C2 










CR1023 


2 


FI 


B1 


C2036 


7 


D4 


C2 


C5033 


8B 


B3 


C5 


CR3031 


8B 


B2 


C3 










C5040 


6 


F2 


D5 


CR4030 


8A 


F3 


C4 


C2037 


7 


E4 


C2 


C5041 


6 


G1 


D5 










C2038 


7 


E4 


C2 


C5042 


6 


G1 


D5 


CR4031 


8B 


A3 


C4 


C2039 


6 


B1 


C2 


C6030 


8B 


E2 


C6 


CR4032 


8B 


C2 


C4 


C2040 


6 


C3 


D2 


C6031 


8B 


B1 


C6 


CR5030 


8B 


C3 


C5 


C2041 


6 


D3 


D2 










CR5040 


8B 


B2 


D5 


C2042 


6 


B3 


D2 


C6032 


8B 


D1 


C6 


CR8020 


8A 


C2 


B8 










C7010 


8B 


G1 


A7 


CR9010 


8A 


G2 


A9 


C2043 


6 


E4 


D2 


C7020 


8B 


G1 


B7 










C2044 


7 


E4 


D2 


C7021 


8B 


El 


B7 


J2010 


1 


C3 


A2 


C2045 


7 


B2 


D2 


C7022 


8B 


F2 


B7 


J5040 f 


1 


E2 


D5 


C2046 


6 


D3 


D2 


C7023 


8B 


D2 


B7 


J6010 


1 


F3 


A6 



t Back Side Components 



9-4 



1502B MTDR Service Manual 



Diagrams 



A1 - MAIN 



CIRCUIT 


SCHEM 


LOCATION 


CIRCUIT 


SCHEM 


LOCATION 


CIRCUIT 


SCHEM 


LOCATION 


NUMBER 


PAGE 


SCHEM 


BRD 


NUMBER 


PAGE 


SCHEM 


BRD 


NUMBER 


PAGE 


SCHEM 


BRD 








J9010 


1 


B2 


A9 


R1032 


2 


Cl 


Cl 


R4043 


6 


H3 


D4 










R1033 


2 


B2 


Cl 


R4044 


6 


H3 


D4 


L5030 


8B 


02 


05 


R1035 


2 


Cl 


Cl 


R4045 


6 


H3 


D4 


L5040 


1 


G2 


D5 


R2010 


5 


F2 


A2 


R4046 


6 


H2 


D4 










R2011 


5 


E2 


A2 


R4047 


6 


H2 


D4 


Q1010 


5 


F3 


A1 


R2012 


5 


FI 


A2 


R4048 


1 


E2 


D4 


Q1020 


2 


FI 


B1 


















Q1021 


2 


F2 


B1 


R2013 


5 


F2 


A2 


R5020 


8B 


A4 


B5 


Q1030 


2 


FI 


Cl 


R2014 


4 


F2 


A2 


R5021 


8B 


B3 


B5 


Q1031 


2 


FI 


Cl 


R2015 


4 


F3 


A2 


R5022 


8B 


B3 


B5 


Q2011 


5 


F2 


A2 


R2030 


7 


FI 


C2 


R5023 


8B 


A3 


B5 










R2031 


7 


D3 


C2 


R5024 


8B 


G3 


B5 


Q2012 


5 


G2 


A2 


R2033 


8B 


Cl 


C2 


R5025 


8B 


G3 


B5 


Q3030 


8A 


E3 


03 


















Q4030 


8A 


F3 


04 


R2034 


8B 


B1 


C2 


R5026 


8B 


E2 


B5 


Q4031 


8B 


B2 


04 


R2040 


6 


E4 


D2 


R5030 


8B 


E2 


C5 


Q4040 


8B 


B2 


D4 


R2041 


7 


G3 


D2 


R5031 


8B 


D2 


C5 


Q5020A 


8B 


E2 


B5 


R2042 


7 


G2 


D2 


R5032 


8B 


D1 


C5 










R2043 


7 


A2 


D2 


R5033 


8B 


C2 


C5 


Q5020B 


8B 


E2 


B5 


R3010 


2 


C2 


A3 


R5034 


8B 


Cl 


C5 


Q5030 


8B 


D2 


05 


















Q5031 


8B 


D2 


05 


R3020 


8A 


C4 


B3 


R5035 


8B 


C2 


C5 


Q5032A 


8B 


02 


05 


R3030 


8A 


D3 


C3 


R6030 


8B 


D2 


C6 


Q5032B 


8B 


02 


05 


R3031 


8A 


C3 


C3 


R6031 


8B 


C2 


C6 


Q6020 


8B 


F2 


B6 


R3032 


8A 


C3 


C3 


R6032 


8B 


Cl 


C6 










R3033 


8A 


C3 


C3 


R6033 


8B 


D1 


C6 


Q7020 


8B 


G2 


B7 


R3034 


8A 


E3 


C3 


R6040 


6 


F4 


D6 


Q7021 


8B 


E2 


B7 


















Q7030 


8B 


D2 


07 


R3035 


8A 


F3 


C3 


R6041 


6 


F3 


D6 


Q8020 


8A 


D2 


B8 


R3036 


8A 


F3 


C3 


R6042 


6 


F3 


D6 


Q9010 


8A 


E2 


A9 


R3037 


8A 


B3 


C3 


R6043 


6 


F3 


D6 


Q9020A 


8A 


02 


B9 


R3038 


8B 


B2 


C3 


R6044 


6 


F3 


D6 










R3039 


8B 


B2 


C3 


R6045 


6 


F3 


D6 


Q9020B 


8A 


D2 


B9 


R3040 


8B 


B2 


D3 


R6046 


6 


F2 


D6 


Q9021 


8A 


B1 


B9 


























R3041 


8B 


A2 


D3 


R6047 


6 


F2 


D6 


R1010 


2 


G2 


A1 


R3042 


8B 


A1 


D3 


R7010 


8A 


G2 


A7 


R1011 


5 


D3 


A1 


R4020 


8A 


D4 


B4 


R7011 


5 


E2 


A7 


R1012 


5 


D3 


A1 


R4021 


8A 


E3 


B4 


R7012 


8B 


G1 


A7 


R1013 


5 


E3 


A1 


R4022 


8A 


C3 


B4 


R7013 


8B 


G1 


A7 


R1014 


5 


F3 


A1 


R4023 


8A 


F3 


B4 


R7014 


8B 


F2 


A7 


R1015 


5 


E3 


A1 


























R4030 


8A 


G3 


C4 


R7015 


8B 


G2 


A7 


R1016 


5 


F3 


A1 


R4031 


8B 


B2 


C4 


R7020 


8B 


F2 


B7 


R1020 


2 


E2 


B1 


R4032 


8B 


B3 


C4 


R7021 


8B 


F2 


B7 


R1021 


2 


FI 


B1 


R4040 


6 


H4 


D4 


R7022 


8B 


FI 


B7 


R1022 


2 


FI 


B1 


R4041 


6 


H3 


D4 


R7023 


8B 


El 


B7 


R1023 


2 


El 


B1 


R4042 


6 


H3 


D4 


R7024 


8B 


FI 


B7 



t Back Side Components 



1502B MTDR Service Manual 



9-5 



Diagrams 



A1 - MAIN 



CIRCUIT 


SCHEM 


LOCATION 


CIRCUIT 


SCHEM 


LOCATION 


CIRCUIT 


SCHEM 


LOCATION 


NUMBER 


PAGE 


SCHEM 


BRD 


NUMBER 


PAGE 


SCHEM 


BRD 


NUMBER 


PAGE 


SCHEM 


BRD 








R7025 


8B 


E2 


B7 


R9023 


8A 


D2 


B9 


U1034 


7 


B1 


Cl 


R7026 


8B 


F2 


B7 


R9024 


8A 


D2 


B9 


U 1040 A 


3 


B3 


D1 


R7027 


8B 


F2 


B7 


R9025 


8A 


C2 


B9 


U1040B 


3 


C3 


D1 


R7028 


8B 


F3 


B7 


R9026 


8A 


B1 


B9 


U1041A 


3 


D4 


D1 


R7029 


8B 


FI 


B7 


R9027 


8A 


B1 


B9 


U1041B 


3 


E4 


D1 


R7030 


8B 


F2 


07 


R9030 


5 


B2 


C9 


U 1042 A 


3 


C4 


D1 


R7031 


8B 


E2 


07 


R9031 


5 


B2 


C9 


U1042B 


3 


B1 


D1 


R7032 


8B 


D2 


07 


R9032 


5 


B2 


C9 


U1042C 


3 


B3 


D1 


R7033 


8B 


D2 


07 










U 1043 A 


2 


D2 


D1 


R7034 


8B 


D2 


07 


TP1040 


2 


Cl 


D1 


U1043B 


3 


E2 


D1 


R7040 


1 


F2 


D7 


TP1041 


7 


El 


D1 


U1043C 


2 


B3 


D1 


R8010 


8A 


F2 


A8 


TP2040 


7 


B1 


D2 


U1043D 


2 


C3 


D1 










TP3040 


7 


G3 


D3 










R8011 


8A 


E2 


A8 


TP3041 


7 


G3 


D3 


U2011 


4 


D1 


A2 


R8012 


8A 


E2 


A8 


TP4020 


8A 


H4 


B4 


U2012A 


4 


D3 


A2 


R8013 


8A 


E2 


A8 










U2012B 


4 


D2 


A2 


R8014 


8A 


D2 


A8 


TP4021 


8A 


H3 


B4 


U2020 


2 


D3 


B2 


R8020 


8A 


D1 


B8 


TP4040 


6 


H2 


D4 


U2021 


3 


E3 


B2 


R8021 


8A 


E2 


B8 


TP6010 


8B 


F4 


A6 


U2022 


3 


G1 


B2 










TP7010 


8B 


G2 


A7 










R8022 


8A 


E2 


B8 


TP9010 


8B 


E3 


A9 


U2023A 


2 


C4 


B2 


R8023 


8A 


E2 


B8 


TP9011 


8A 


G2 


A9 


U2023B 


3 


G3 


B2 


R8024 


8A 


D2 


B8 










U2024 


3 


F2 


B2 


R8025 


8A 


02 


B8 


TP9040 


8A 


B2 


D9 


U2025A 


7 


FI 


B2 


R8026 


8A 


B2 


B8 


TP9041 


6 


A2 


D9 


U2025B 


7 


G1 


B2 


R8027 


8A 


B1 


B8 










U2026 


3 


F2 


B2 










U1010 


2 


G2 


A1 










R8028 


8A 


B1 


B8 


U1011A 


4 


D4 


A1 


U2027A 


7 


C4 


B2 


R8040 


6 


E3 


D8 


U1 01 1 B 


5 


C3 


A1 


U2027B 


7 


A4 


B2 


R8041 


6 


E3 


D8 


U1012A 


5 


E2 


A1 


U2030 


7 


B2 


C2 


R8042 


6 


E3 


D8 


U1012B 


5 


E3 


A1 


U2031 


7 


Cl 


C2 


R8043 


6 


E2 


D8 


U1020 


2 


G3 


B1 


U2032 


7 


C2 


C2 


R8044 


6 


02 


D8 










U2033A 


3 


B2 


C2 










U1021 


2 


E3 


B1 










R8045 


6 


02 


D8 


U1022 


2 


E2 


B1 


U2033B 


7 


FI 


C2 


R8046 


6 


02 


D8 


U1023 


2 


D1 


B1 


U2034A 


7 


G1 


C2 


R8047 


6 


02 


D8 


U1030 


2 


B1 


Cl 


U2034B 


7 


E2 


C2 


R9010 


8A 


H2 


A9 


U1031A 


2 


G2 


Cl 


U2034C 


7 


C3 


C2 


R9011 


8A 


H2 


A9 


U1031B 


2 


Cl 


Cl 


U2034D 


7 


B4 


C2 


R9012 


8A 


F2 


A9 










U2036 


7 


E2 


C2 










U1031C 


3 


B2 


Cl 










R9013 


8A 


FI 


A9 


U1031D 


2 


Cl 


Cl 


U2037 


7 


E3 


C2 


R9014 


8A 


E2 


A9 


U1031E 


2 


A2 


Cl 


U2040A 


6 


B3 


D2 


R9015 


8A 


El 


A9 


U1031F 


2 


A3 


Cl 


U2040B 


5 


B3 


D2 


R9020 


8A 


El 


B9 


U1032A 


2 


B1 


Cl 


U2040C 


3 


C2 


D2 


R9021 


8A 


Cl 


B9 


U1032B 


2 


B2 


Cl 


U2040D 


7 


El 


D2 


R9022 


8A 


02 


B9 










U2041 


6 


C3 


D2 



t Back Side Components 



9-6 



1502B MTDR Service Manual 



Diagrams 



A1 - MAIN 



CIRCUIT 

NUMBER 



SCHEM LOCATION 

PAGE SCHEM BRD 



U2042A 


7 


D1 


D2 


U2042B 


7 


D1 


D2 


U2043 


7 


D3 


D2 


U2044 


6 


B1 


D2 


U2045A 


7 


G2 


D2 


U2045B 


7 


G3 


D2 


U2045C 


7 


G3 


D2 


U2046 


6 


B3 


D2 


U3010 


2 


B3 


A3 


U3020A 


3 


F4 


B3 


U3020B 


3 


F4 


B3 


U3020C 


3 


B3 


B3 


U3020D 


3 


B4 


B3 


U3021 


8A 


B3 


B3 


U3022 


8A 


B4 


B3 


U3023 


8A 


03 


B3 


U3040 


6 


B3 


D3 


U3041 


6 


B2 


D3 


U3042 


6 


G2 


D3 


U4020 


8B 


03 


B4 


U4021A 


8A 


D4 


B4 


U4021B 


8A 


G3 


B4 


U4040 


6 


G3 


D4 


U5010 


8B 


E4 


A5 


U5020 


8B 


B4 


B5 


U5040 


6 


E2 


D5 


U6040 


6 


E3 


D6 


U7010A 


8A 


G1 


A7 


U7010B 


8A 


D3 


A7 


U7040 


6 


D2 


D7 


U8010A 


8A 


G2 


A8 


U8010B 


8A 


F2 


A8 


U8010C 


8A 


F2 


A8 


U8040 


6 


D3 


D8 


U8041 


6 


02 


D8 


U9030 


5 


Cl 


09 


VR3030 


8A 


B3 


03 


VR6030 


8B 


Cl 


06 



t Back Side Components 



1502B MTDR Service Manual 



9-7 



Diagrams 



A2 - FRONT PANEL 



CIRCUIT 


SCHEM 


LOCATION 


CIRCUIT 


SCHEM 


LOCATION 


CIRCUIT 


SCHEM 


LOCATION 


NUMBER 


PAGE 


SCHEM 


BRD 


NUMBER 


PAGE 


SCHEM 


BRD 


NUMBER 


PAGE 


SCHEM 


BRD 








C1011 


10 


D1 


A1 


R1021 


10 


Cl 


B1 


U2020A 


10 


B1 


B2 


Cl 01 5 


10 


B1 


A1 


R 1022 A 


10 


C3 


B1 


U2020B 


10 


C3 


B2 


C2010 


10 


A3 


A2 


R1022B 


10 


C4 


B1 


U2021 


10 


Cl 


B2 


C2011 


10 


A3 


A2 


R1023 


10 


C2 


B1 


U2022A 


99 


F2 


B2 


C2020 


10 


Cl 


B2 


R1024 


10 


B1 


B1 


U2022B 


10 


B1 


B2 


C2021 


10 


El 


B2 


R1025 


10 


B1 


B1 


U2022B 


99 


F2 


B2 


C2022 


10 


E2 


B2 


R1026 


10 


A1 


B1 


U2022C 


10 


B2 


B2 


C2023 


10 


G4 


B2 


R1027 


10 


C3 


B1 


U2023 


10 


E3 


B2 


C2024 


10 


B1 


B2 


R1030 


10 


D2 


Cl 


U2024 


10 


G1 


B2 


C2025 


10 


B3 


B2 


R1031 


10 


D2 


Cl 


U2025 


10 


G2 


B2 


C2026 


10 


E4 


B2 


R2010 


10 


B2 


A2 


U3020A 


10 


B3 


B3 


C2027 


10 


B3 


B2 


R2020 


10 


FI 


B2 


U3020B 


10 


B3 


B3 


C2028 


10 


E4 


B2 


R2021 


10 


B3 


B2 


U3020C 


10 


B3 


B3 


C2030 


10 


Cl 


C2 


R2022 


10 


Cl 


B2 


U3020D 


10 


B3 


B3 


C2031 


10 


C3 


C2 


R2024A 


10 


A3 


B2 


U3021A 


10 


B1 


B3 


C2032 


10 


C4 


C2 


R2024B 


10 


A3 


B2 


U3021B 


99 


C2 


B3 


C2033 


10 


D3 


C2 


R2030 


10 


D4 


C2 


U3021C 


10 


B2 


B3 


C2034 


10 


D4 


C2 


R2031 


10 


E4 


C2 


U3021D 


10 


B2 


B3 


C3010 


10 


A4 


A3 


R2032 


10 


D3 


C2 


U3022A 


10 


B3 


B3 


C3020 


10 


H4 


B3 


R2034 


10 


B3 


C2 


U3022B 


10 


B3 


B3 


C3021 


10 


Cl 


B3 


R2035 


10 


B3 


C2 


U3022C 


10 


B2 


B3 


C3022 


10 


Cl 


B3 


R2036 


10 


C3 


C2 


U3022D 


10 


B3 


B3 


C3023 


10 


B1 


B3 


R2037 


10 


C4 


C2 


U3023A 


10 


B4 


B3 


C3030 t 


10 


D3 


C3 


R2038 


10 


D3 


C2 


U3023B 


10 


B3 


B3 


C3031 t 


10 


D3 


C3 


R3010 


10 


B4 


A3 


U3023C 


10 


B4 


B3 


C3032 


10 


C3 


C3 


R3011 


10 


B3 


A3 


U3023D 


10 


B4 


B3 


C3033 


10 


C3 


C3 


R3020A 


10 


D4 


B3 


U3025 


10 


G2 


B3 


C3034 


10 


B4 


C3 


R3020B 


10 


D4 


B3 


U3031 


10 


G3 


C3 










R3024 


10 


D1 


B3 










J1020 t 


10 


FI 


Cl 


R3031 


10 


El 


C3 










J3030 f 


10 


HI 


C3 


























S1010 


10 


A2 


A1 










PS2030 t 


10 


F2 


C2 


S1011 


10 


A2 


A1 


















S2010 


10 


A3 


A2 










Q1020 


10 


Cl 


B1 


S2011 


10 


A3 


A2 










Q1030 


10 


D3 


Cl 


S3010 


10 


A4 


A3 










Q2020 


10 


A1 


B2 


S3012 


10 


C2 


A3 










R1010 


10 


B2 


A1 


S3020 


10 


E2 


B3 










R1011 


10 


D1 


A1 


S3021 


10 


D3 


B3 










R1012 


10 


E2 


A1 


S3022 


10 


C4 


B3 










R1013 


10 


B2 


A1 


















R1014 


10 


D1 


A1 


U2010A 


10 


D1 


A2 










R1020 


10 


D1 


B1 


U2010B 


99 


D2 


A2 











t Back Side Components 



9-8 



1502B MTDR Service Manual 



Diagrams 



A3A1 - POWER SUPPLY 



CIRCUIT 


SCHEM 


LOCATION 


CIRCUIT 


SCHEM 


LOCATION 


CIRCUIT 


SCHEM 


LOCATION 


NUMBER 


PAGE 


SCHEM 


BRD 


NUMBER 


PAGE 


SCHEM 


BRD 


NUMBER 


PAGE 


SCHEM 


BRD 








C1010 t 


1 A 


B2 


A1 


CR2010 


1 A 


E3 


A2 


R1017 


1 A 


D3 


A1 


C1011 


1 A 


B3 


A1 


CR2011 


1 A 


G2 


A2 


R1018 


1 A 


C4 


A1 


C1012 


1 A 


C4 


A1 


CR2012 


1 A 


G2 


A2 


R1020 


1 A 


B6 


B1 


C1013 


1 A 


F2 


A1 


CR2013 


1 A 


G2 


A2 


R1021 


1 A 


B5 


B1 


C1014 


1 A 


D3 


A1 


CR2014 


1 A 


G2 


A2 


R1022 


1 A 


B7 


B1 


Cl 01 5 


1 A 


C4 


A1 


CR2015 


1 A 


G2 


A2 


R1023 


1 A 


B7 


B1 


Cl 01 6 


1 A 


C4 


A1 


CR2016 


1 A 


A5 


A2 


R1024 


1 A 


C7 


B1 


Cl 030 


1 A 


G5 


Cl 


CR2020 


1 A 


D7 


B2 


R1025 


1 A 


C6 


B1 


Cl 031 


1 A 


G5 


Cl 


CR2021 


1 A 


D6 


B2 


R1026 


1 A 


E7 


B1 


Cl 032 


1 A 


F4 


Cl 


CR2030 


1 A 


F6 


C2 


R1030 


1 A 


G5 


Cl 


Cl 033 


1 A 


F4 


Cl 


CR2031 


1 A 


F6 


C2 


R2010 


1 A 


F2 


A2 


Cl 034 


1 A 


F3 


Cl 










R2011 


1 A 


F2 


A2 










J1010 


1 A 


B2 


A1 










Cl 035 


1 A 


F4 


Cl 


J1030 


1 A 


G4 


Cl 


R2012 


1 A 


G2 


A2 


Cl 036 


1 A 


G5 


Cl 


J2010 


1 A 


H2 


A2 


R2013 


1 A 


A6 


A2 


Cl 037 


1 A 


G5 


Cl 










R2014 


1 A 


A6 


A2 


Cl 038 


1 A 


F6 


Cl 


LI 01 0 


1 A 


E3 


A1 


R2015 


1 A 


B6 


A2 


C2010 


1 A 


F3 


A2 


L2020 


1 A 


D6 


B2 


R2016 


1 A 


A5 


A2 


C2011 


1 A 


A5 


A2 










R2017 


1 A 


A5 


A2 










Q1010 


1 A 


E2 


A1 










C2012 


1 A 


F3 


A2 


Q1011 


1 A 


F2 


A1 


R2018 


1 A 


B5 


A2 


C2013 


1 A 


B6 


A2 


Q1012 


1 A 


E2 


A1 


R2020 


1 A 


C7 


B2 


C2020 


1 A 


C7 


B2 


Q2010 


1 A 


B6 


A2 


R2021 


1 A 


D7 


B2 


C2021 


1 A 


D5 


B2 


Q2011 


1 A 


B5 


A2 


R2022 


1 A 


D7 


B2 


C2022 


1 A 


C7 


B2 


Q2012 


1 A 


B5 


A2 


R2023 


1 A 


D7 


B2 


C2023 


1 A 


C7 


B2 










R2024 


1 A 


C7 


B2 










Q2020 


1 A 


D7 


B2 










C2024 


1 A 


E7 


B2 


Q2021 


1 A 


D8 


B2 


R2025 


1 A 


D7 


B2 


C2025 


1 A 


E6 


B2 


Q2022 


1 A 


D7 


B2 


R2026 


1 A 


D8 


B2 


C2030 


1 A 


E8 


C2 


Q2030 


1 A 


F6 


C2 


R2027 


1 A 


D7 


B2 


C2031 


1 A 


G6 


C2 


Q2031 


1 A 


F6 


C2 


R2030 


1 A 


G6 


C2 


















R2031 


1 A 


G4 


C2 


CR1010 


1 A 


B2 


A1 


R1010 


1 A 


B3 


A1 


R2032 


1 A 


G7 


C2 


CR1011 


1 A 


E3 


A1 


R1011 


1 A 


B3 


A1 










CR1030 


1 A 


F4 


Cl 


R1012 


1 A 


B3 


A1 


S2010 


1 A 


A5 


A2 


CR1031 


1 A 


F5 


Cl 


R1013 


1 A 


C3 


A1 










CR1032 


1 A 


F5 


Cl 


R1014 


1 A 


D2 


A1 


T1030 


1 A 


F5 


Cl 


CR1033 


1 A 


F5 


Cl 


R1015 


1 A 


B3 


A1 


T1031 


1 A 


G6 


Cl 


CR1034 


1 A 


F3 


Cl 


R1016 


1 A 


B3 


A1 


TP1010 


1 A 


A3 


A1 



t Back Side Components 



1502B MTDR Service Manual 



9-9 



Diagrams 



A3A1 - POWER SUPPLY 



CIRCUIT 

NUMBER 



SCHEM LOCATION 

PAGE SCHEM BRD 



TP1020 


1 A 


G2 


B1 


TP2010 


1 A 


B2 


A2 


TP2030 


1 A 


E6 


C2 


U1010 


1 A 


C4 


A1 


U1011 


1 A 


D3 


A1 


U 1020 A 


1 A 


B6 


B1 


U1020B 


1 A 


B6 


B1 


U1021A 


1 A 


B7 


B1 


U1021B 


1 A 


B8 


B1 


U1 022 


1 A 


C6 


B1 


U1023 


1 A 


C7 


B1 


U1024B 


1 A 


E7 


B1 


U2010 


1 A 


G2 


A2 


U2030A 


1 A 


E8 


C2 


U2030B 


1 A 


F7 


C2 


U2030C 


1 A 


F7 


C2 


U2030D 


1 A 


F7 


C2 


U2030E 


1 A 


F7 


C2 


VR1012 


1 A 


D2 


A1 



t Back Side Components 



9-10 



1502B MTDR Service Manual 



Diagrams 



A4- SIR DRIVER SAMPLER 



CIRCUIT 


SCHEM 


LOCATION 


CIRCUIT 


SCHEM 


LOCATION 


CIRCUIT 


SCHEM 


LOCATION 


NUMBER 


PAGE 


SCHEM 


BRD 


NUMBER 


PAGE 


SCHEM 


BRD 


NUMBER 


PAGE 


SCHEM 


BRD 








C1010 


9A 


E5 


A1 


C3061 


9A 


B2 


F3 


R1062 


9A 


C5 


FI 


C1011 


9A 


E5 


A1 


C3062 


9A 


A1 


F3 


R1063 


9A 


C5 


FI 


Cl 020 


9A 


D2 


B1 


C3063 


9A 


C2 


F3 


R1064 


9A 


C5 


FI 


Cl 030 


9A 


F2 


Cl 


C3064 


9A 


A1 


F3 


R1065 


9A 


D4 


FI 


Cl 040 


9A 


D2 


D1 


C3065 


9A 


B2 


F3 


R1066 


9A 


D5 


FI 


Cl 041 


9A 


B3 


D1 


C3070 


9A 


A2 


G3 


R1070 


9A 


D4 


G1 


Cl 050 


9A 


F7 


El 


C3080 


9A 


B2 


H3 


R1071 


9A 


D4 


G1 


Cl 060 


9A 


G7 


FI 










R1072 


9A 


D5 


G1 


Cl 061 


9A 


F8 


FI 


CR1030 


9A 


B4 


Cl 


R2030 


9A 


B4 


C2 


Cl 070 


9A 


D4 


G1 


CR1031 


9A 


F2 


Cl 


R2031 


9A 


B4 


C2 


Cl 071 


9A 


D5 


G1 


CR1032 


9A 


F3 


Cl 


R2040 


9A 


B3 


D2 


C2010 


9A 


E2 


A2 


CR1040 


9A 


D1 


D1 


R2041 


9A 


B4 


D2 










CR2050 


9A 


E7 


E2 










C2011 


9A 


E5 


A2 


CR2051 


9A 


E6 


E2 


R2042 


9A 


F6 


D2 


C2012 


9A 


E4 


A2 










R2043 


9A 


F7 


D2 


C2020 


9A 


E3 


B2 


CR2052 


9A 


E7 


E2 


R2045 


9A 


A4 


D2 


C2021 


9A 


E3 


B2 


CR3020 


9A 


B5 


B3 


R2046 


9A 


C6 


D2 


C2022 


9A 


E3 


B2 


CR3021 


9A 


C5 


B3 


R2047 


9A 


D6 


D2 


C2023 


9A 


E4 


B2 










R2048 


9A 


D6 


D2 










J3040 


9A 


G3 


D3 










C2024 


9A 


E4 


B2 










R2049 


9A 


D6 


D2 


C2025 


9A 


E3 


B2 


L2080 


9A 


A7 


H2 


R2050 


9A 


E7 


E2 


C2026 


9A 


E4 


B2 


L2081 


9A 


A7 


H2 


R2051 


9A 


D6 


E2 


C2030 


9A 


B4 


C2 










R2052 


9A 


D7 


E2 


C2031 


9A 


B6 


C2 


Q1030 


9A 


E2 


Cl 


R2053 


9A 


E7 


E2 


C2040 


9A 


B4 


D2 


Q1060 


9A 


E6 


FI 


R2054 


9A 


E7 


E2 










Q2030 


9A 


B4 


C2 










C2041 


9A 


F6 


D2 


Q2040 


9A 


D6 


D2 


R3020 


9A 


B5 


B3 


C2042 


9A 


A4 


D2 


Q2050 


9A 


D6 


E2 


R3021 


9A 


B6 


B3 


C2050 


9A 


F7 


E2 










R3032 


9A 


F4 


C3 


C2051 


9A 


D6 


E2 


R1010 


9A 


E4 


A1 


R3033 


9A 


E4 


C3 


C2052 


9A 


D7 


E2 


R1020 


9A 


C4 


B1 


R3040 


9A 


B7 


D3 


C2053 


9A 


E7 


E2 


R1030 


9A 


El 


Cl 


R3050 


9A 


A1 


E3 










R1031 


9A 


E2 


Cl 










C2072 


9A 


A2 


G2 


R1040 


9A 


D1 


D1 


R3051 


9A 


B2 


E3 


C2080 


9A 


B8 


H2 


R1041 


9A 


D2 


D1 


R3061 


9A 


A1 


F3 


C2081 


9A 


B7 


H2 










R3062 


9A 


A2 


F3 


C2082 


9A 


B8 


H2 


R1042 


9A 


D2 


D1 


R3070 


9A 


A2 


G3 


C2083 


9A 


B7 


H2 


R1050 


9A 


F7 


El 


R3071 


9A 


B2 


G3 


C3010 


9A 


E5 


A3 


R1051 


9A 


F7 


El 


R3080 


9A 


B1 


H3 










R1052 


9A 


G7 


El 










C3011 


9A 


E5 


A3 


R1053 


9A 


F8 


El 


T1020 


9A 


C4 


B1 


C3020 


9A 


B5 


B3 


R1060 


9A 


F6 


FI 










C3030 


9A 


C7 


C3 










TP1020 


9A 


E5 


B1 


C3060 


9A 


A1 


F3 


R1061 


9A 


D6 


FI 


TP1021 


9A 


D4 


B1 



t Back Side Components 



1502B MTDR Service Manual 



9-11 



Diagrams 



A4 - SIR DRIVER SAMPLER 



CIRCUIT 

NUMBER 



SCHEM LOCATION 

PAGE SCHEM BRD 



TP1030 


9A 


E2 


Cl 


TP1060 


9A 


G7 


FI 


TP1080 


9A 


B2 


HI 


TP1081 


9A 


C2 


HI 


TP1082 


9A 


F2 


HI 


TP1083 


9A 


B7 


HI 


TP1084 


9A 


B7 


HI 


TP2060 


9A 


E6 


F2 


TP3020 


9A 


B5 


B3 


U1010 


9A 


E5 


A1 


U 1050 A 


9A 


F7 


El 


U1050B 


9A 


D2 


El 


U 1070 A 


9A 


D5 


G1 


U1070B 


9A 


C5 


G1 


U2050A 


9A 


F6 


E2 


U2050B 


9A 


F5 


E2 


U2070 


9A 


A2 


G2 


U3030A 


9A 


B5 


C3 


U3030B 


9A 


C6 


C3 


U3070A 


9A 


B2 


G3 


U3070B 


9A 


A2 


G3 



t Back Side Components 



9-12 



1502B MTDR Service Manual 



Diagrams 



A9 - POWER FUSE JACK (Option 03 - Battery Pack) 



CIRCUIT 

NUMBER 


SCHEM 

LOCATION 


BOARD 

LOCATION 




F9100 


D3 


PWRSUPP 



1502B MTDR Service Manual 



9-13 



Diagrams 



9-14 



1502B MTDR Service Manual 



Replaceable Mechanical Parts 



This section contains a list of the replaceable mechanical components for the 1 502B . 
Use this list to identify and order replacement parts. 



Parts Ordering Information 

Replacement parts are available through your local Tektronix field office or 
representative. 

Changes to Tektronix instruments are sometimes made to accommodate improved 
components as they become available and to give you the benefit of the latest circuit 
improvements. Therefore, when ordering parts, it is important to include the 
following information in your order. 

■ Part number 

■ Instrument type or model number 

■ Instrument serial number 

■ Instrument modification number, if applicable 

If you order a part that has been replaced with a different or improved part, your local 
Tektronix field office or representative will contact you concerning any change in 
part number. 

Change information, if any, is located at the rear of this manual. 



Using the Replaceable Mechanical Parts List 

The tabular information in the Replaceable Mechanical Parts List is arranged for 
quick retrieval. Understanding the structure and features of the list will help you find 
all of the information you need for ordering replacement parts. The following table 
describes the content of each column in the parts list. 



1502B MTDR Service Manual 



10-1 




Replaceable Mechanical Parts 



Parts List Column Descriptions 



Column 


Column Name 


Description 


1 


Figure & Index Number 


Items in this section are referenced by figure and index numbers to the exploded view illustrations 
that follow. 


2 


Tektronix Part Number 


Use this part number when ordering replacement parts from Tektronix. 


3 and 4 


Serial Number 


Column three indicates the serial number at which the part was first effective. Column four indicates 
the serial number at which the part was discontinued. No entries indicates the partis good for all 
serial numbers. 


5 


Qty 


This indicates the quantity of parts used. 


6 


Name & Description 


An item name is separated from the description by a colon (:). Because of space limitations, an item 
name may sometimes appear as incomplete. Use the U.S. Federal Catalog handbook H6-1 for 
further item name identification. 


7 


Mfr. Code 


This indicates the code of the actual manufacturer of the part. 


8 


Mfr. Part Number 


This indicates the actual manufacturer's or vendor's part number. 



Abbreviations Abbreviations conform to American National Standard ANSI Yl. 1-1972. 



Chassis Parts Chassis-mounted parts and cable assemblies are located at the end of the 
Replaceable Electrical Parts List. 



Mfr. Code to Manufacturer 
Cross Index 



The table titled Manufacturers Cross Index shows codes, names, and addresses of 
manufacturers or vendors of components listed in the parts list. 



10-2 



1502B MTDR Service Manual 



Replaceable Mechanical Parts 



Manufacturers Cross Index 



Mfr. 



Code 


Manufacturer 


Address 


City, State, Zip Code 


0DWW6 


MICRO PWER ELECTRONICS 


7973 SW CIRRUS DRIVE, BLDG. #22 


BEAVERTON, OR 97005 


0JRZ2 


BADGLEY MFG CO 


1620 NEARGYLE 


PORTLAND, OR 97211 


0JRZ5 


GASKETTECHNOLOGY 


478 NE 219TH AVENUE 


TROUTDALE, OR 97060 


0JR05 


TRIQUESTCORP 


3000 LEWIS AND CLARK HWY 


VANCOUVER, WA 98661-2999 


OJ 244 


OBATA WORKS, TJ BO LIAISON 


19-030 


BEAVERTON, OR 


OJ 260 


COMTEK MANUF OF OREGON 


PO BOX 4200 


BEAVERTON, OR 97076-4200 


OJ 422 


PRECISION PRINTERS 


PO BOX 36 


CEDAR RIDGE, CA 95924 


0J4Z1 


TVT DIECASTING AND MFG INC 


7330 SW LANDMARK LANE 


PORTLAND, OR 97223 


OJ9P4 


DELTAENGINEERING 


19500 SW TETON 


TUALATIN, OR 97062 


OKBOl 


STAUFFER SUPPLY 


810 SE SHERMAN 


PORTLAND, OR 97214 


S3109 


FELLER 


72 VERONICA AVE, UNIT 4 


SUMMERSER, NJ 08873 


S3629 


SCHURTER AG H 
C/OPANELCOMPONENTSCORP 


2015 SECOND STREET 


BERKELEY, CA 94170 


00779 


AMP INC 


2800 FULLING MILL 
PO BOX 3608 


HARRISBURG, PA 17105 


01536 


TEXTRON INC, CAMCAR DIV 


1818 CHRISTINA ST 


ROCKFORD, IL 61108 


03038 


LONG-LOK FASTENER CORP 


13709 S NORMANDIE AVE 


GARDENA CAS, CA 90249-2609 


06540 


MITE CORP 

AMATOM ELECTRONIC HARDWARE DIV 


446 BLAKE ST 


NEW HAVEN, CT 06515-1238 


06915 


RICHCO PLASTIC CO 


5825 N TRIPP AVE 


CHICAGO, IL 60646-6013 


08261 


SPECTRA-STRIP AN ELTRACO 


7100 LAMPSON AVE 


GARDEN GROVE, CA 92642 


09922 


BURNDYCORP 


RICHARDS AVE 


NORWALK, CT 06852 


12327 


FREEWAY CORP 


9301 ALLEN DR 


CLEVELAND, OH 44125-46-32 


2K262 


BOYD CORP 


6136 NE 87TH AVE 
PO BOX 20038 


PORTLAND, OR 97220 


2X013 


MCGUIRE BEARING CO 


947 SE MARKET ST 


PORTLAND, OR 97214-3556 


22526 


DU POITE IDE NEMOURS ANDCO INC 
DU PONTELECTRONICS DEPT 


515 FISHING CREEK RD 


NEW CUMBERLAND, PA 17070-3007 


22599 


AMERACE CORP, ESNA DIV 


15201 BURBANK BLVD, SUITE C 


VAN NUYS, CA 91411-3532 


28334 


3-D POLYMERS 


13026 NORMANDIE AVE 


GARDENA, CA 90249-2126 


29870 


VICTOR CORP 


618 MAIN STREET 


WEST WARWICK, Rl 02893 


5H194 


AIR-OIL PRODUCTS CORP 


2400 E BURNSIDE 


PORTLAND, OR 97214-1752 


5Y400 


TRIAX METAL PRODUCTS INC 


1800 216TH AVE NW 


HILLSBORO, OR 97124-6629 


53217 


TECHNICAL WIRE PRODUCTS INC 


320 N NOPAL ST 


SANTA BARBARA, CA 93103-3225 



10-3 

1502B MTDR Service Manual 



Replaceable Mechanical Parts 



Manufacturers Cross Index (Cont.) 



Mfr. 



Code 


Manufacturer 


Address 


City, State, Zip Code 


53387 


MINNESOTA MINING MFG CO 


PO BOX 2963 


AUSTIN, TX 78769-2963 


53718 


GRACE W R AND CO 
POLYFIBRON DIV/AIRMOLD 


BECKER FARMS INDUSTRIAL PARK 
PO BOX 610 


ROANOKE RAPIDS, NC 27870 


7X318 


KASO PLASTICS INC 


11015 A NE 39TH 


VANCOUVER, WA 98662 


70903 


COOPER BELDEN ELECTRONICS WIRE & 
CABLE BELDEN DIVISION 


2200 US HIGHWAY 27 SOUTH 
PO BOX 1980 


RICHMOND, IN 47375 


72228 


AMCA INTERNATIONAL CORP 
CONTINENTAL SCREW CO DIV 


459 MT PLEASANT 


NEW BEDFORD, MA 02742 


72794 


DZUS FASTENER CO INC 


425 UNION BLVD 


WEST IS LIP , NY 11795-3123 


73743 


FISCHER SPECIAL MFG CO 


111 INDUSTRIAL RD 


COLD SPRING, KY 41076-9749 


74970 


JOHNSON E F COMPANY 


299 10TH AVE SW 


WASECA, MN 56093-2539 


78189 


ILLINOIS TOOL WORKS INC 
SHAKEPROOF DIV 


ST CHARLES ROAD 


ELGIN, IL 60120 


79136 


WALDES KOHINOOR INC 


47-16 AUSTEL PLACE 


LONG ISLAND CITY, NY 11101-4402 


80009 


TEKTRONIX INC 


14150 SW KARL BRAUN DR 
PO BOX 500 


BEAVERTON, OR 97077-0001 


83259 


PARKER-HANNIFIN CORP, O-SEAL DIV 


10567 J EFFERSON BLVD 


CULVER CITY, CA 90232-3513 


83385 


MICRODOT MFG INC, GREER-CENTRAL DIV 


3221 W BIG BEAVER RD 


TROY, Ml 48098 


86445 


PENN FIBRE AND SPECIALTY CO INC 


4343 G ST 


PHILADELPHIA, PA 19124-4325 



10-4 



1502B MTDR Service Manual 



Replaceable Mechanical Parts 



Replaceable Mechanical Parts List 



Fig. & 



Index 

Number 


Tektronix Part 
Number 


Serial No. 
Effective 


Serial No. 
Discont’d 


Qty 


Name & Description 


Mfr. 

Code 


Mfr. Part Number 


FIG. 10-1 










CABINET 








650-3676-00 






1 


COVER, LID ASSY:LID/COVER ASSEMBLY 


7X318 


650-3676-00 


-1 


105-0684-01 






2 


.LATCH ASSEMBLY: 


0J4C1 


105-0684-01 


-2 


213-0839-00 






2 


. S C R ,TP G ,TF :4- 24 X 0.5 L,FLH,POZ 


80009 


213-0839-00 


-3 


214-0787-00 






1 


. STE M,LATCH :ACCESS BOX 


80009 


214-0787-00 


-4 


204-0282-00 






1 


.BODY LATC H :ACC ESS BOX,DE LR IN 


80009 


204-0282-00 


-5 


214-2389-00 






2 


. PIN, ACTUATOR:POWER SWITCH 


80009 


214-2389-00 


-6 


334-6861-00 






1 


MARKER, IDENT:MARKED 1502B 


0J4Z2 


334-6861-00 


-7 


062-9291-00 






1 


CARD,INFO:QUICK REFERENCE 


0J4Z2 


062-9291-00 




334-8896-00 






1 


MARKER, IDENT:VOLTAGE WARNING LABEL 


80009 


334-8896-00 




437-0337-00 






1 


CAB.JDR UNIT: 


80009 


437-0337-00 


-8 


200-1805-00 






2 


. COVER, HDL LATCH: 


0JR05 


200-1805-00 


-9 


213-0739-00 






2 


. SCR, MACH:1 0-32 X 0.375, HEX HD,SSTW/NYLON 


03038 


213-0739-00 


-10 


210-1231-00 






2 


.WSHR,SHLDR:0.82 X 0.9 X 0.07, FBR 


80009 


210-1231-00 


-11 


386-3303-01 






2 


. PLATE, SECURING:HANDLE, STEEL 


80009 


386-3303-01 


-12 


107-0035-00 






4 


. DISC,FRICTION:0.38 X 1.865 X 0.031, ASB 


2K262 


107-0035-00 


-13 


210-1501-00 


B037303 




4 


. WS H R,F RICTION :1.820 X 0.388, 304SS 20GA 


80009 


210-1501-00 


-14 


334-9302-00 






1 


. MARKER, IDENT:MARKED TEKTRONIX 


0J4Z2 


334-9302-00 


-15 


367-0204-01 


B010100 


B037302 


1 


. HANDLE, CARRY:11.7 L,BLK VINYL W/HDW 


0J9P4 


367-0204-01 




347-0449-00 


B037303 




1 


. HANDLE, CARRYBACK VINYL, 302 SST 


80009 


347-0449-00 


-16 


390-0964-00 


R010100 


B024999 


1 


.CABINET ASSY: 


7X318 


390-0964-00 




390-1068-00 


B025000 


B037105 


1 


. CABINET ASSY:CONDUCTIVE PLATE 


7X318 


390-1068-00 




390-0964-00 


B037106 




1 


.CABINET ASSY: 


7X318 


390-0964-00 


-17 


348-0419-00 






2 


. . FOOT,CABINET:FRONT,BLK POLYURETHANE 


7X318 


348-0419-00 


-18 


211-0507-00 






4 


. . SCR, MACH:6-32 X 0.31 2, PNH, POZ 


0KB01 


211-0507-00 


-19 


348-0420-01 






2 


. . FOOT,CABINET:REAR,BLK POLYURETHANE 


7X318 


348-0420-01 


-20 


213-0451-02 






4 


. . SCR, EXT, RLV:10-24X 1.75, SST, PSVT 


80009 


213-0451-02 


-21 


354-0175-00 






4 


. . RING,RTNG:TYPEE EXT, U/O 0.188 


2X013 


354-0175-00 


-22 


348-0444-00 






4 


. . SEAL,BOLT:0.1 86 X 0.443,0.05 THK 


80009 


348-0444-00 


-23 


386-4704-00 






2 


. . PLATE, REINF:3.8X 0.434, STL 


7X318 


386-4704-00 


-24 


213-0183-00 






2 


. . SC R,TPG,TF:6-20X 0.5, TYPES, PNH, POZ 


93907 


ORD BY DESCR 


-25 


131-1705-00 


R010100 


B025092 


1 


. . CONN,RCPT,ELEC:POWER INTERCONNECT 


80009 


131-1705-00 




131-1705-01 


B025093 




1 


. . CONN,RCPT,ELEC:POWER INTERCONNECT 


80009 


131-1705-01 


-26 


213-0012-00 






2 


. . SCR,TPG,TC:4-40 X 0.375, FLH, POZ 


83385 


ORD BY DESCR 



1502B MTDR Service Manual 



10-5 



Replaceable Mechanical Parts 



Replaceable Mechanical Parts List (Cont.) 



Fig. & 
Index 
Number 


Tektronix Part 
Number 


Serial No. 
Effective 


Serial No. 
Discont’d 


Qty Name & Description 


Mfr. 

Code Mfr. Part Number 


FIG. 10-1 








CABINET (Con’t) 





-27 


337-3225-00 


B025000 


B036153 


1 


. S H IE LD ( ELEC:G ROUND AROUND AC RCPT 


80009 


337-3225-00 


-28 


200-3210-00 






1 


.COVER, TUBE CAP:CLOSED, ALUMINUM 


80009 


200-3210-00 


-29 


354-0675-00 


R010100 


R020413 


1 


. O- R IN G :0.5 X 0.625 OD 


5H194 


2-014 




354-0688-00 


R020414 






. O- R IN G :0.424 X 0.625 OD X 0.093 THK 


83259 


2-111 


-30 


200-3211-00 






1 


.COVER, TUBE CAP:OPEN, ALUMINUM 


80009 


200-3211-00 


-31 


354-0675-00 


R010100 


R020413 


1 


. O- R IN G :0.5 X 0.625 OD 


5H194 


2-014 




354-0688-00 


R020414 




1 


. O- R IN G :0.424 X 0.625 OD X 0.093 THK 


83259 


2-111 


-32 


331-0501-00 






1 


. WINDOW, VIEW:POLYCARB, OPTICAL GRADE 


80009 


331-0501-00 




200-3452-00 


R010100 


B024999 


1 


COVER, BATTERY:ALUMINUM 


80009 


200-3452-00 




200-3452-01 


B025000 




1 


COVER, BATTERY:ALUMINUM 


80009 


200-3452-01 


-33 


333-3434-00 


R010100 


B021134 


1 


. PANEL FRONT :BATTE RY PORT, 2.72 X 3.562, AL 


80009 


333-3434-00 




333-3434-01 


B021135 




1 


. PANEL FRONT:BATTERY PORT, 2.72 X 3.562, AL 


5Y400 


333-3434-01 


-34 


214-1573-00 






2 


. THUMBSRCREW:6-32 X 0.656 X 0.31 2, SST 


06540 


6130-SS-0632 


-35 


210-1160-00 






2 


. WSHR,FLAT:0.129 X 0.25 X 0.031 TEFLON 


86445 


ORD BY DESCR 


-36 


348-0432-00 


R010100 


B021134 


1 


. GASKET:FRONT PANEL 


2K262 


348-0432-00 




348-1143-00 


B021135 


B035824 


1 


. GASKET, COND:ELASTOMER W/ALUMINUM 


0JRZ5 


348-1143-00 




348-1143-01 


B035825 




1 


. GASKET, BATTERY:0.062 X 2.600 X 2.600 


0JRZ5 


348-1143-01 




334-6892-00 






1 


LABELMARKED CAUTION 


0J4Z2 


334-6892-00 




334-6864-02 


B025330 




1 


MRKR,IDENT:W/VOLTAGE INFORMATION 


0J4Z2 


334-6864-02 












STANDARD ACCESSORIES 






-37 


161-0066-09 






1 


CA ASSY,PWR:3,0.75MM SQ, 220V, 99.0 L 
(OPTION A1 EUROPEAN ONLY) 


S3109 


86511000 


-38 


161-0066-10 






1 


CA ASSY,PWR:3,0.75MM SQ, 250V, 2.5 METERS 
(OPTION A2 UNITED KINGDOM ONLY) 


S3109 


BS/13-H05VVF3G0 


-39 


161-0066-11 






1 


CA ASSY,PWR:3,1.00MM S Q, 250V, 10AM P, 2, 5 
(OPTION A3 AUSTRALIA ONLY) 


S3109 


SAA/3-OD3CCFC3 


-40 


161-0066-12 






1 


CA ASSY, PWR:3,18AWG, 250V, 99.0 L 


29870 


ORD BY DESCR 












(OPTION A4 NORTH AMERICA ONLY) 






-41 


161-0154-00 






1 


CA ASSY, PWR:3, 0.75mm SQ,240V,6A,2.5ML 
(OPTION A5 SWITZERLAND ONLY) 


S3109 


12-H05VVF3G 00-5 


-42 


161-0228-00 






1 


CA ASSY, PWR:3, 18 AWG, 98.0 L (STANDARD CABLE) 


70903 


FH49061 



ALL OF THE CABLES LISTED ARE SAFETY CONTROLLED 



10-6 



1502B MTDR Service Manual 



Replaceable Mechanical Parts 



Replaceable Mechanical Parts List (Cont.) 



Fig. & 

Index Tektronix Part Serial No. Serial No. Mfr. 

Number Number Effective Discont’d Qty Name & Description Code Mfr. Part Number 

FIG. 10-1 CABINET (Con’t) 



016-0814-00 
070- 6266- XX 



P0UCH,ACCESS:11.5 X 9.5 X 1.75 H, VINYL 
MANUAL, TECH:OPERATORS,1502BTDR 



0JRZ2 016-0814-00 
80009 070- 6266-XX 



1502B MTDR Service Manual 



10-7 



Replaceable Mechanical Parts 



Replaceable Mechanical Parts List (Cont.) 



Fig. & 



Index 

Number 


Tektronix Part 
Number 


Serial No. 
Effective 


Serial No. 
Discont’d 


Qty 


Name & Description 


Mfr. 

Code 


Mfr. Part Number 


FIG. 10-2. 










FRAME AND FRONT PANEL 






-1 


366-2097-00 






4 


SHELL, KNOB:DOVE GRAY, 0.060 X 0.375 


0JR05 


366-2097-00 


-2 


366-2104-00 






1 


KN 0 B :S ET REF/W DOT SET FOR 90 


0JR05 


366-2104-00 


-3 


366-2098-00 






2 


SHELL, KNOB:DOVE GRAY W/INDEX DOT 


0JR05 


366-2098-00 












EACH KNOB INCLUDES: 








213-0153-00 






1 


. SETSCREW:5-40 X 0.125, STL, HEX SKT 


0KB01 


ORDER BY DESCR 


-4 


131-4178-00 






1 


CONN, RCPT,ELEC:BNC, FEMALE SHORTING 


91836 


752-17-9 


-5 


650-3697-00 






1 


DUSTCOVER ASSEMBLY 


5Y400 


650-3697-00 


-6 










SUBPARTOF ASSEMBLY -5ABOVE 














1 


SWITCH, ROTARY (1503B/3C ONLY)) 














1 


SWITCH, ROTARY (SEEA2S3012) 














1 


RESISTOR, VARIABLE (SEE A2R3020 REPL) 














1 


SWITCH ROTARY (SEE A2S3020 REPL) 














1 


SWITCH ROTARY (SEE A2S3021 REPL) 














1 


SWITCH ROTARY (SEE A2S3022 REPL) 














1 


SWITCH ROTARY (1503B/3C ONLY) 














1 


RESISTOR, VARIABLE (SEE A2R2024 REPL) 














1 


RESISTOR, VARIABLE (SEE A2R1022 REPL) 
















EACH SWITCH AND VARIABLE RESISTOR INCLUDES: 






-7 


210-0583-00 






1 


.NUT, PLAIN HEX:0.25-32 X 0.312 


73743 


2X-20319-402 


-8 


210-0940-00 






1 


. WS H R ,F LAT :0.25 X 0.375 X 0.02, STL CD PL 


12327 


ORD BY DESCR 












EACH VARIABLE RESISTOR INCLUDES: 






-9 


354-0581-00 






1 


. O- R IN G :0.25 X 0.062 OD XSECT 


5H194 


2-010-S455-70 


-10 


348-1145-00 


B021135 


B035824 


1 


.SEAL, ROTARY POT:0.125 X 0.187 OD 


80009 


348-1145-00 




348-1145-01 


B035825 






. SEAL, CONT SHAFT:0.125 X 0.187 OD X 0.3 L 


80009 


348-1145-01 


-11 


366-0655-05 






1 


PUSH BUTTON:MENU, 0.523 X 0.253 


0JR05 


366-0655-05 


-12 


366-0655-01 






1 


PUSH BUTTON :VIEW INPUT 


0JR05 


366-0655-01 


-13 


366-0655-02 






1 


PUSH BUTTON:VIEW STORE 


0JR05 


366-0655-02 


-14 


366-0655-03 






1 


PUSH BUTT O N :VIE W DIFF 


0JR05 


366-0655-03 


-15 


366-0655-04 






1 


PUSH BUTTO N :STO R E 


0JR05 


366-0655-04 


-16 


334-6664-00 


R010100 


B025495 


1 


MARKER, IDENT:MARKED 1502B 


0J 4Z2 


334-6664-00 




334-6664-01 


B025496 




1 


MARKER, IDENT:MARKED 1502B 


0J4Z2 


334-6664-01 



10-8 



1502B MTDR Service Manual 



Replaceable Mechanical Parts 



Replaceable Mechanical Parts List (Cont.) 



Fig. & 
Index 
Number 


Tektronix Part 
Number 


Serial No. 
Effective 


Serial No. 
Discont’d 


Qty 


Name & Description 


Mfr. 

Code 


Mfr. Part Number 


FIG. 10-2 










FRAME AND FRONT PANEL (Con’t) 






-17 


213-1089-00 






4 


SCREW, TYPE-F:6-32 X .500,FLH,POS,410 SS 


80009 


213-1089-00 


-18 


386-5307-00 


R010100 


B021134 


1 


SUBPANEL,FRONT: 


0J4C1 


386-5307-00 




386-5307-01 


B021135 


B025495 


1 


SUBPANEL,FRONT: 


0J4C1 


386-5307-01 




614-0389-01 


B025496 




1 


FRONTPANELASSEMBLY 


80009 


614-0389-01 


-19 


348-0477-00 


R010100 


B021134 


2 


SEAL,RBR STRIP :0.94W X 0.062THK X 28.0L 


2K262 


R- 10460 




348-0477-00 


B021135 




1 


. S E AL,R B R STR IP :0.94W X 0.062THK X 28.0L 


2K262 


R- 10460 


-20 


348-1116-00 


B021135 


B037137 


1 


SEAL, CONDUCTIVE:0.094X 0.062 


53217 


87-90279 




348-0477-00 


B037138 




1 


. SEAL,RBR STRIP :0.94W X 0.062THK X 28.0L 


2K262 


R- 10460 


-21 


348-0976-00 


R010100 


B021134 


1 


SHLD GSKT,ELEC:2.53 X 3.255 X 0.62 SILICON 


2K262 


348-0976-00 




348-1144-00 


B021135 




1 


. GASKET, COND:ELASTOMER W/AL 


0JRZ5 


348-1144-00 


-22 


348-0920-00 






1 


. SHLD GSKT,ELEC:PUSH BUTTON 


28334 


348-0920-00 


-23 


331-0502-00 






1 


. WINDOW, DSP, PORT:2.295 X 4.35 X 0.125, GLASS 


80009 


331-0502-00 


-24 








1 


CKT BDASSY:FRONT PANEL (SEE A2REPL) 






-25 


211-0658-00 






4 


SCR,ASSEM WSHR:6-32X 0.312, PNH,POZ 


78189 


S51-060545-0X 


-26 








AR 


. CONN, HDR:PCB, MALE (SEE A2REPL) 






-27 


131-0993-00 






1 


. . BUS CONDUCTORS HU NT/SHORTING, FEMALE 


22526 


65474-006 


-28 








1 


. CONN, HDR:PCB, MALE (SEE A2REPL) 






-29 


342-0731-00 


R010331 


B035824 


1 


IN S U LATO R :FISHPAPER,3.6 X 3.0 


80009 


342-0731-00 




342-0731-01 


B035825 




1 


IN S U LATO R :F ISHPAPER,3.6 X 3.0 


80009 


342-0731-01 


-30 








1 


DISPLAY MODULE:(SEE A5 REPL) 






-31 


220-0407-00 






4 


NUT, SLFLKG, HEX:6-32 X 0.312 HEX 


22599 


22NM-62 


-32 


337-2193-02 


R010100 


B035824 


2 


SHIELD, ELEC:EMI, BOTTOM 


0J 260 


337-2193-02 




337-2193-04 


B035825 




2 


SHIELD, ELEC:EMI, BOTTOM 


0J 260 


337-2193-04 




211-0661-00 






7 


SCR,ASSEM WSHR:4-40 X 0.25,PNH,POZ 


01536 


821-01655-024 




129-1092-00 






1 


SPACER, POST:0.605 L, 4-40, HEX 


80009 


129-1092-00 




210-1307-00 






1 


WHSR,LOCK:0. 1 15 ID, SPLIT 


0KB01 


ORD BY DESCR 




210-1002-00 






1 


WSHR,FLAT:0. 125 X 0.25 ODX0.022 


12327 


ORD BY DESCR 




334-8135-00 


B035976 


B037458 


1 


M KR ,IDE NT :M KD EMI SHIELD INSTRU 


0J4Z2 


334-8135-00 












(NOT ILLUSTRATED ATTHIS TIME) 






-33 


650-3714-00 






1 


ON/OFF SHAFT ASSEMBLY 


TK2545 


650-3714-00 


-34 








1 


SHAFT ASSEMBLY INCLUDES. O-RING:0.031 X 0.93 OD 







1502B MTDR Service Manual 



10-9 



Replaceable Mechanical Parts 



Replaceable Mechanical Parts List (Cont.) 



Fig. & 



Index 

Number 


Tektronix Part 
Number 


Serial No. 
Effective 


Serial No. 
Discont’d 


Qty 


Name & Description 


Mfr. 

Code 


Mfr. Part Number 


FIG. 10-2 










FRAME AND FRONT PANEL (Con’t) 






-35 


220-0961-00 






1 


NUT B LO C K:6- 32 X 0.438, AL, CHROMATE 


5Y400 


220-0961-00 


-36 


213-0004-00 


R010100 


R010399 


1 


. SETSCREW:6-32 X 0.188, HEX, CUP PT 


80009 


213-0004-00 




213-0966-00 


R010400 




1 


. SETSCREW:6-32 X 0.188 HEX,W/NYLON 


80009 


213-0966-00 


-37 


354-0687-00 


R010100 


R 010513 


1 


RING,RETAINER:BOWED,SFT 


79136 


5131- 12- C D 




211-0005-00 


R 010514 




3 


S C R ,M AC H :4- 40 X 0.125,PNH,POZ 


0KB01 


ORD BY DESCR 


-38 


210-0803-00 


R010100 


R020513 


1 


WSHR,FLAT:0.15 X 0.375 ODX 0.032 


12327 


ORD BY DESCR 




210-0851-00 


R020514 




3 


WSHR,FLAT:0.119 X 0.375 ODX 0.025 


12327 


ORD BY DESCR 


-39 


105-0954-00 


R010100 


R020513 


1 


LEVER:3.25L X 0.5W X 0.05,AL 


80009 


105-0954-00 




105-0954-01 


R020514 




1 


LEVER:3.25L X 0.5W X 0.05,AL 


80009 


105-0954-01 




210-1421-00 


R010100 


R020513 


1 


SHWR,SHLDR:0.136 X 0.375 OD X 0.24, NYLON 


80009 


210-1421-00 


-40 


384-1674-00 


R010100 


R020513 


1 


EXTENSION S HAFT :7.59 L X 0.5,AL 


80009 


384-1674-00 




384-1674-01 


R020514 




1 


EXTENSION S HAFT :7.59 L X 0.5,AL 


80009 


384-1674-01 




211-0007-00 


R010100 


R020513 


1 


SCR, MACH :4-40 X O. 188,PNH,POZ 


93907 


ORD BY DESCR 




210-1092-00 


R010100 


R020513 


1 


WHSR,FLAT:0. 147X0.312 OD X 0.028 


12327 


ORD BY DESCR 


-41 


650-3699-00 






1 


CHART EXTRUSION ASSEMBLY 


5Y400 


650-3699-00 


-42 


212-0001-00 






2 


SCR, MACH :8-32 X 0.25,PNH,POZ 


80009 


212-0001-00 


-43 


210-0008-00 






2 


WSHR,LOCK:#8, INTL, 0. 02 THK 


0KB01 


ORD BY DESCR 


-44 


210-0458-00 






1 


NUT,PL,ASSEM WA:8-32 X 0.344 


0KB01 


ORD BY DESCR 


-45 








1 


CA ASSY: (SEE W2010 WIRE ASSEMBLIES) 








200-3497-00 


R010100 


B021134 


1 


COVER, PORT:1502B 


80009 


200-3497-00 




200-3737-00 


B021135 




1 


COVER, FRONT:OPTION PORT 


0J 260 


200-3737-00 












COVER PORT INCLUDES: 






-46 


200-3451-00 


R010100 


B021134 




. COVER, PORT:1502B 


80009 


200-3451-00 




200-3451-01 


B021135 






. COVER, PORT:1502B 


80009 


200-3451-01 


-47 


348-0912-00 


R010100 


B021134 


1 


. GASKET :2.41 X 3.16 X 0.062 REINF SI W/PSA 


2K262 


348-0912-00 




348-1118-00 


B021135 


B035824 


1 


. GASKET, COND:ELASTOMER W/AL 


0JRZ5 


348-1118-00 




348-1118-01 


B035825 




1 


. GASKET :0 PTIO N PORT COVER, 0.062 THK 


0JRZ5 


348-1118-01 


-48 


105-0959-00 


R010100 


B025509 


1 


. LC H ,0 PT PORT COVER:STEEL,ZINC PLATE 


72794 


DZUSDP109SMOD 




105-0959-01 


B025510 




1 


. LC H ,0 PT PORT COVER:STEEL,ZINC PLATE 


72794 


DZUSDP109SMOD 


-49 


407-3675-00 


B021134 




1 


. F R AM E :0 PTIO N PORTCOVER 


0J 260 


407-3675-00 


-50 


213-0123-00 


B021134 




2 


. S C R ,TP G ,TF :6- 32 X 0.375, FLH100 DEG,POZ 


72228 


ORD BY DESCR 



10-10 



1502B MTDR Service Manual 



Replaceable Mechanical Parts 



Replaceable Mechanical Parts List (Cont.) 



Fig. & 



Index 

Number 


Tektronix Part 
Number 


Serial No. 
Effective 


Serial No. 
Discont’d 


Qty 


Name & Description 


Mfr. 

Code 


Mfr. Part Number 


FIG. 10-2 










FRAME AND FRONT PANEL (Con’t) 






-51 


200-3123-00 






1 


COVER, MODULE:FRONT 


80009 


200-3123-00 


-52 


348-0974-00 






2 


SHLD GSKT,ELEC:FRONT COVER 


2K262 


348-0974-00 


-53 


211-0661-00 






2 


SCR,ASSEM WSHR:4-40 X 0.25,PNH,POZ 


01536 


821-01655-024 


-54 








1 


CKT BD ASSY: (SEE A4REPL) 






-55 


131-0391-00 






1 


. CONN,RF J ACK:SMB,50 OHM (1503B/3C ONLY) 


98291 


051-051-0049 


-56 


131-3360-00 






1 


. CONN, HDR:PCB, MALE, SHRD/4SIDES 


53387 


2520-6002UB 


-57 


407-1694-00 


B010100 


B037562 


1 


BRACKET, RTNG:AL 


5Y400 


407-1694-00 


-58 


211-0513-00 


B010100 


B037562 


1 


SCR,MACH:6-32 X 0.625, PNH 


93907 


B80- 00032-003 


-59 


210-0055-00 


B010100 


B037562 


1 


WSHR,LOCK:#6 SPLIT, 0.031 THK 


86928 


ORD BY DESCR 


-60 


256-0570-00 


B010100 


B037562 


1 


DEHYDRATING AGENT:SILICA GEL 


53718 


X- 1009 


-61 


129-0562-00 


B010100 


B037562 


2 


POST, RETAINERS. 892 L X 0.375 HEX,AL 


80009 


129-0562-00 


-62 


441-1683-00 






1 


CHASSIS, FRONT:AL 


0J 260 


441-1683-00 


-63 


211-0198-00 


R010100 


B020819 


2 


SCR, MACH :4-40 X -.438, PNH, POZ 


80009 


211-0198-00 




211-0661-00 


B020820 




2 


SCR,ASSEM WSHR:4-40X 0.25, PNH, POZ 


01536 


821-01655-024 




210-1307-00 


R010100 


B020819 


2 


WSHR,LOCK:0.115 ID, SPLIT 


0KB01 


ORD BY DESCR 


-64 


211-0661-00 


R010100 


B020819 


1 


SCR,ASSEM WSHR:4-40X 0.25, PNH, POZ 


01536 


821-01655-024 




211-0007-00 


B020820 




1 


SCR,MACH:4-40 X 0. 188, PNH, POZ 


93907 


ORD BY DESCR 


-65 


210-1307-00 


B037618 




1 


WSHR,LOCK:0. 1 15 ID, SPLIT 


0KB01 


ORD BY DESCR 


-66 


351-0755-00 






4 


GUIDE, CKT BD:POLYCARBONATE, 2.5 L 


06915 


TCG 1-2.500-03 










1 


CA ASSY: (SEE WIRE ASSEMBLIES) 






-67 


210-0586-00 






1 


NUT,PL,ASSEM W:4-40 X 0.25 (1503B/3C O N LY ) 


0KB01 


ORD BY DESCR 


-68 








1 


POWERSUPPLY ASSY: (SEE A3 REPL) 






-69 


211-0007-00 






1 


SCR,MACH:4-40 X 0. 188, PNH, POZ 


83385 


ORD BY DESCR 




211-0105-00 






1 


SCR,MACH:4-40 X 0. 188,FLH,POZ 


83385 


ORD BY DESCR 




211-0661-00 






1 


SCR,ASSEM WSHR:4-40X 0.25, PNH, POZ 


01536 


821-01655-024 


-70 


211-0198-00 






2 


SCR,MACH:4-40 X 0..438,PNH,POZ 


80009 


211-0198-00 


-71 


210-0005-00 






1 


WSHR,LOCK:#6 EXT, 0.02 THK, STL, CD PL 


78189 


1106-00 


-72 








1 


CKT BD ASSY: (SEE A1 REPL) 






-73 


211-0661-00 






9 


SCR,ASSEM WSHR:4-40X 0.25, PNH, POZ 


01536 


821-01655-024 


-74 


131-3361-00 






1 


. CONN, HDR:PCD, MALE, RTANG W/SHRD 


53387 


2526-5002UB 


-75 


131-3181-00 






1 


. CONN, HDR:PCB, MALE, RTANG W.SHRD 


53387 


2540-5002UB 


-76 


131-3359-00 






1 


. CONN, HDR:PCB, MALE, 2X10 


53387 


2520-5002UB 


-77 


136-0755-00 






1 


. S KT,DIP :F E M ALE ,2 X 14 


09922 


DILB28P- 108 



10-11 

1502B MTDR Service Manual 



Replaceable Mechanical Parts 



Replaceable Mechanical Parts List (Cont.) 



Fig. & 



Index 

Number 


Tektronix Part 
Number 


Serial No. 
Effective 


Serial No. 
Discont’d 


Qty 


Name & Description 


Mfr. 

Code 


Mfr. Part Number 


FIG. 10-2 










FRAME AND FRONT PANEL (Con’t) 






-78 


131-4183-00 






1 


. CONN, HDR:PCB, MALE, 2X7 


53387 


2514-6002UB 


-79 


213-0904-00 






4 


SCR,TPG,TR:6-32 X 0.5 PNH,TORX 


93907 


ORD BY DESCR 


-80 


441-1682-00 


R010100 


R020513 


1 


CHASSIS, MAIN:AL 


80009 


441-1682-00 




441-1682-01 


R020514 


B035824 


1 


CHASSIS, MAIN:AL 


80009 


441-1682-01 




441-1682-03 


B035825 




1 


CHASSIS, MAIN:AL 


80009 


441-1682-03 



10-12 



1502B MTDR Service Manual 



Replaceable Mechanical Parts 



Replaceable Mechanical Parts List (Cont.) 



Fig. & 
Index 
Number 


Tektronix Part 
Number 


Serial No. 
Effective 


Serial No. 
Discont’d 


Qty 


Name & Description 


Mfr. 

Code 


Mfr. Part Number 


FIG. 10-3 


620-0477-XX 








POWER SUPPLY ASSEMBLY 






-1 








1 


CKT BD ASSY :(S E E A3A1 RE PL) 






-2 


211-0661-00 






4 


SCR,ASSEM WSHR:4-40 X 0.25,PNH,POZ 


01536 


821-01655-024 


-3 


131-3445-00 






1 


. CONN, HDR:MALE,RTANG, 2X7 


53387 


2514-5002UB 


-4 


131-4177-00 






AR 


. CONN, HDR:MALE,STR, 1X31 W/INSUL 


22562 


65576-131 


-5 


131-1857-00 






AR 


. CONN, HDR:MALE,STR, 1X36 


58050 


082-3644-SS10 










1 


. XSTR: (SEE A3A1Q2022 REPL) 






-6 


211-0507-00 






1 


. SCR,MACH:6-32X 0.312, PNH,POZ 


0KB01 


211-0507-00 


-7 


210-0561-00 






1 


. NUT,PL,HEEX:6-32 X 0.188 


0KB01 


210-0561-00 










1 


. 1C: (SEE A3A1U 2010 REPL) 






-8 


211-0507-00 






1 


. SCR,MACH:6-32X 0.312, PNH,POZ 


0KB01 


211-0507-00 


-9 


210-0561-00 






1 


. NUT,PL,HEEX:6-32 X 0.188 


0KB01 


210-0561-00 




253-0188-00 






1 


.TAPE, PRESS S E NS :LI RETHAN E FOAM 


80009 


253-0188-00 




162-0503-00 


R 010141 




AR 


. INSUL SLVG,ELEC:0.042 ID/AC RY LIC/F B R G LASS 


91094 


ORD BY DESCR 


-10 


220-0547-01 






4 


NUT BLOCK:4-40 X 0.282 


80009 


220-0547-01 


-11 


211-0105-00 






4 


SCR, MACH :4-40 X 0. 188,FLH,POZ 


80009 


211-0105-00 


-12 


441-1685-00 






1 


CHASSIS, PWRSUPPLY:SIDE 


80009 


441-1685-00 


-13 


211-0105-00 






3 


SCR,MACH:4-40 X 0. 188,FLH,POZ 


80009 


211-0105-00 












CHASSIS MOUNTED PARTS 






-14 








1 


XFMR: (SEE A3T201 REPL) 






-15 


212-0112-00 






2 


SCR, MACH :8-32 X 0. 188, TRH,SST,POZ 


0KBO1 


ORD BY DESCR 


-16 


210-0007-00 






2 


WSHR,LOCK:#8 EXT, 0.02 THK 


0KBO1 


ORD BY DESCR 


-17 








1 


SWITCH, ROTARY: (SEEA3S201 REPL) 






-18 


204-0832-00 






1 


BODY,FUSEHLDR:3AG &5X20MM FUSES 


S3629 


031 1673 


-19 


200-2264-00 






1 


CAP,FUSEHLDR:3AG FUSES, SFTY CONTROL 


S3629 


FEK 031 1666 


-20 








1 


FILTER, RF: (SEE A3FL1 REPL) 






-21 


211-0101-00 






2 


S CR,MACH:4-40 X 0.25, FLH, 100 DEG,POZ 


93907 


ORD BY DESCR 


-22 


210-0202-00 






1 


TERMINAL, LUG:0.146 ID, LOCKING 


86928 


A- 373- 158- 2 



1502B MTDR Service Manual 



10-13 



Replaceable Mechanical Parts 



Replaceable Mechanical Parts List (Cont.) 



Fig. & 



Index 

Number 


Tektronix Part 
Number 


Serial No. 
Effective 


Serial No. 
Discont’d 


Qty 


Name & Description 


Mfr. 

Code 


Mfr. Part Number 


FIG. 10-3 


620-0477-XX 








POWER SUPPLY ASSEMBLY (Con’t) 
















CHASSIS MOUNTED PARTS (Con’t) 






-23 


211-0658-00 






1 


SCR,ASSEM, WA:6-32 X 0.312,PNH,POZ 


78189 


S51-060545-0X 


-24 


134-0014-00 






2 


PLUG, TIP:BANANA, 1.125 X 0.375 L STUD 


74970 


108-0750-001 


-25 


210-0202-00 






2 


TERMINAL, LUG:0. 146 ID, LOCKING 


86928 


A- 373- 158- 2 


-26 


210-0975-00 






2 


WSHR,SHLDR:0. 14 X 0.375 OD X 0. 1,DELRUN 


80009 


210-0975-00 


-27 


210-0457-00 






2 


NUT,PL,ASSEM WA:6-32X0.312 


0KBO1 


ORD BY DESCR 


-28 


210-0803-00 






1 


WSHR,FLAT:0. 15 X 0.375 OD X 0.032 


12327 


ORD BY DESCR 


-29 


210-0933-00 






1 


INSULA TOR, WSHR:0. 165 C 0.625 OD X 0.002 


OKB01 


210-0933-00 


-30 


441-1684-00 


R010100 


B021134 


1 


CHASSIS, PWR SUPPLY: 


80009 


441-1684-00 




441-1684-01 


B021135 




1 


CHASSIS, PWR SUPPLY: 


80009 


441-1684-01 




334-3379-01 






1 


MARKER, IDENT:MKD GROUND SYMBOL 


22670 


ORD BY DESCR 



10-14 



1502B MTDR Service Manual 



Replaceable Mechanical Parts 



Replaceable Mechanical Parts List (Cont.) 



Fig. & 



Index 

Number 


Tektronix Part 
Number 


Serial No. 
Effective 


Serial No. 
Discont’d 


Qty 


Name & Description 


Mfr. 

Code 


Mfr. Part Number 


FIG. 10-4 










BATTERY PACK OPTION 03 








016-0813-00 


R010100 


B021134 


1 


BTRY ASSY.STORE :1.2V,2000M AH/0.2C 


80009 


016-0813-00 




016-0813-01 


B021135 




1 


BTRY ASSY, STORE :1.2V, 2000MAH/0.2C,C CELL(9) 


0DWW6 


016-0813-01 


-1 


214-1573-00 






2 


. THUMBSCREWS- 32 X 0.656, 0.312, SST 


06540 


6130-SS-0632 


-2 


210-1160-00 






2 


. WS H R ,F LAT :0.129l D X 0.25OD X 0.031, TEFLON 


86928 


5612-32-31 


-3 


333-1990-00 


R010100 


B021134 


1 


. PANEL, FRONT:UNFINISHED 


80009 


333-1990-00 




333-1990-02 


B021135 




1 


. PANEL, FRONT:BATTERY SET 


0J9P4 


333-1990-02 


-4 


334-6867-00 






1 


. LABEL-MARKED BATTERY STORAGE TEMP 


0J4Z2 


334-6867-00 


-5 


211-0198-00 






4 


. SCR,MACH:4-40 X 0.438, PNH,POZ 


80009 


211-0198-00 


-6 


213-0267-00 






2 


. SCR, TPG, TC:4-24 X 0.375 PAN HD,POZ 


0KB01 


ORD BY DESCR 


-7 


348-0432-00 


R010100 


B021134 


1 


. GASKET:FRONT PANEL 


2K262 


348-0432-00 




348-1143-00 


B021135 


B035824 


1 


. GASKET, COND:ELASTOMER W/AL 


0JRZ5 


348-1143-00 




348-1143-01 


B035825 




1 


. GASKET, BATTERY:0.062 THK X 2.600 X 2.600 


0JRZ5 


348-1143-01 


-8 


337-2762-00 






1 


. SHIELD, FUSE:AL 


0J9P4 


337-2762-00 


-9 


211-0008-00 






4 


. SCR,MACH:4-40 X 0.25,PNH,POZ 


93907 


ORD BY DESCR 


-10 


343-0349-01 






2 


. CLAMP, BATTERY RTN G :W/H O LE S ,DE LR IN 


0J 260 


343-0349-01 


-11 


210-0406-00 






4 


. NUT, PLAIN, HEX:4-40 X 0. 188 


73743 


12161-50 


-12 


211-0194-00 






4 


. SCR,MACH:4-40 X 47.5MM,PNH,POZ 


0KBO1 


ORD BY DESCR 


-13 


210-0054-00 






4 


. WSHR,LOCK:#4 SPLIT, 0.025 THK 


86928 


ORD BY DESCR 


-14 


361-0776-00 






4 


. SPACER, SLEEVE:1.248 L X 0.118 ID, NYLON 


80009 


361-0776-00 


-15 


214-2344-00 






1 


. HEAT SINK, ELEC:BATTERY SPLY, LOWER, AL 


0J9P4 


214-2344-00 


-16 








1 


. CKT BD ASSY: (SEE A9REPL) 






-17 


136-0352-00 






2 


..SOCKET, PIN TERM:U/W 0.02 DIA PINS 


00779 


50462-7 


-18 


386-2435-00 






2 


. P LATE ,METALLIC:W/TAPS 


0J 244 


386-2435-00 


-19 


146-0065-00 






1 


. BATTERY, DRY:(9) 1.4V,200MA,NICAD 


0DWW6 


146-0065-00 


-20 


214-2343-00 






1 


. HEAT S IN K,E LE C :BATTE RY SPLY,UPPER,AL 


0J9P4 


214-2343-00 


-21 








1 


. FUSE, THERMAL: (SEE A9F9100REPL) 







1502B MTDR Service Manual 



10-15 



Replaceable Mechanical Parts 



Replaceable Mechanical Parts List (Cont.) 



Fig. & 

Index Tektronix Part Serial No. Serial No. Mfr. 

Number Number Effective Discont’d Qty Name & Description Code Mfr. Part Number 



10-16 



1502B MTDR Service Manual 



Glossary 



Aberrations 


Imperfections or variations from a desired signal. In TDRs, a pulse of electrical 
energy is sent out over the cable. As the pulse-generating circuitry is turned on and 
off, the pulse is often distorted slightly and no longer is a perfect step or sine-shaped 
waveform. 


AC 


Alternating current is a method of delivering electrical energy by periodically 
changing the direction of the flow of electrons in the circuit or cable. Even electrical 
signals designed to deliver direct current (DC) usually fluctuate enough to have an 
AC component. 


Accuracy 


The difference between a measured, generated, or displayed value and the true value. 


Cable 


Electrical conductors that are usually insulated and often shielded. Most cables are 
made of metal and are designed to deliver electrical energy from a source (such as 
a radio transmitter) across a distance to a load (such as an antenna) with minimal 
energy loss. Most cables consist of two conductors, one to deliver the electrical 
signal and another to act as a return path, which keeps both ends of the circuit at 
nearly the same electrical potential. In early electrical systems and modem systems 
that over long distances use the earth and/or air as the return path, and the term 
“ground” or “ground wire” is often used to describe one of the wires in a cable pair. 


Cable Attenuation 


The amount of signal that is absorbed in the cable as the signal propagates down it. 
Cable attenuation is typically low at low frequencies and higher at high frequencies 
and should be corrected for in some TDR measurements. Cable attenuation is 
usually expressed in decibels at one or several frequencies. See also: dB and Series 
Loss. 


Cable Fault 


Any condition that makes the cable less efficient at delivering electrical energy than 
it was designed to be. Water leaking through the insulation, poorly mated 
connectors, and bad splices are typical types cable faults. 


Capacitance 


(see Reactance) 


Characteristic Impedance 


Cables are designed to match the source and load for the electrical energy that they 
carry. The designed impedance is often called the characteristic impedance of the 
cable. The arrangement of the conductors with respect to each other is the major 
factor in designing the impedance of cables. 



1 502B MTDR Service Manual Glossary-1 




Glossary 



Conductor 


Any substance that will readily allow electricity to flow through it. Good conductors 




are metals such as silver, copper, gold, aluminum, and zinc (in that order). 


dB 


dB is an abbreviation for decibel. Decibels are a method of expressing power or 
voltage ratios. The decibel scale is logarithmic. It is often used to express the 
efficiency of power distribution systems when the ratio consists of the energy put 
into the system divided by the energy delivered (or is some cases, lost) by the 
system. Our instrument measures return loss. The formula for decibels is: dB = 2- 
log (Vi/Vl) where Vi is the voltage of the incident pulse, VI is the voltage reflected 
back by the load, and log is the decimal-based logarithmic function. The dB vertical 
scale on our instrument refers to the amount of voltage gain (amplification) the 
instrument applies to the signal before displaying it. For example, when the 
instrument is amplifying the voltage by one hundred, the dB scale would read 40 
dB, which is 20 log 100. 


DC 


Direct current is a method of delivering electrical energy by maintaining a constant 
flow of electrons in one direction. Even circuits designed to generate only AC often 
have a DC component. 


Dielectric 


(see Insulation) 


Domain 


A mathematical term that refers to the set of numbers that can be put into a function 
(the set of numbers that comes out of the function is called the “range”). A 
time-domain instrument performs its function by measuring time. 


Impedance 


The total opposition to the flow of electrical energy is a cable or circuit. Impedance 
is made partly of resistance (frequency independent) and partly of reactance 
(frequency dependent). Although impedance is expressed in units of Ohms, it must 
not be confused with the simple resistance that only applies to DC signals. 
Technically, impedance is a function of the frequency of the electrical signal, so it 
should be specified at a frequency. As a practical matter, the impedance of most 
cables changes very little over the range of frequencies they are designed for. 


Impedance Mismatch 


A point in a cable or system where the incident electrical energy is redistributed into 
absorbed, reflected, and/or transmitted electrical energy. The transmitted electrical 
energy after the mismatch is less than the incident electrical energy. 


Incident Pulse 


The pulse of electrical energy sent out by the TDR. The waveform shown by the 
TDR consists of this pulse and the reflections of it coming back from the cable or 
circuit being tested. 


Inductance 


(see Reactance) 



Glossary-2 



1502B MTDR Service Manual 



Glossary 



Insulation 


A protective coating on an electrical conductor that will not readily allow electrical 
energy to flow away from the conductive part of the cable or circuit. Insulation is 
also called dielectric. The kind of dielectric used in a cable determines how fast 
electricity can travel through the cable (see Velocity of Propagation). 


Jitter 


The short term error or uncertainty in the clock (timebase) of a TDR. If the timing 
from sample to sample is not exact, the waveform will appear to move back and forth 
rapidly. 


LCD 


An acronym for Liquid Crystal Display. It is the kind of display used on this 
instrument, so the terms display and LCD are often used interchangeably. 


Millirho 


rho (p) is the reflection coefficient of a cable or power delivery system. It is the ratio 
of the voltage reflected back from the cable or circuit due to cable faults or an 
impedance mismatch at the load, divided by the voltage applied to the cable. 
Millirho are thousandths of one rho. Rho measurements are often used to judge how 
well the cable is matched to the load at the other end of the cable. If there is an open 
circuit in the cable, nearly all the energy will be reflected back when a pulse is sent 
down the cable. The reflected voltage will equal the incident pulse voltage and rho 
will be +1. If there is a short circuit in the cable, nearly all the energy will be 
delivered back to the instrument through the ground or return conductor instead of 
being sent to the load. The polarity of the reflected pulse will be the opposite of the 
incident pulse and rho will be -1 . If there is no mismatch between the cable and the 
load, almost no energy will be reflected back and rho will be 0. In general, a load 
or fault with higher impedance than the cable will return a rho measurement of 0 to 
+1, and a load or fault with a lower impedance will return a rho measurement of 0 
to -1. The scale for rho measurements is determined by the height of the incident 
pulse. A pulse two divisions high means that each division is 0.5 rho (500 millirho). 
A pulse set to be four divisions high would make each division 0.25 rho (250 
millirho). 


Noise 


Any unwanted electrical energy that interferes with a signal or measurement. Most 
noise is random with respect to the signals sent by the TDR to make a measurement 
and will appear on the waveform, constantly constantly moving up and down on the 
display. The NOISE FILTER control sets how many waveforms will be averaged 
together to make the waveform displayed. Noisy waveforms appear to fluctuate 
around the real signal. Because it is random, noise will sometimes add to the real 
signal and sometimes subtract energy from the real signal. By adding several noisy 
waveforms together, the noise can be “averaged” out of the signal because the 
average amount of noise adding to the signal will be nearly the same as the average 
amount of noise subtracting from the signal. More waveforms in an average are 
more likely to approach the real signal (although it takes longer to acquire and add 
together more waveforms). 



1502B MTDR Service Manual Glossary-3 



Glossary 



Open Circuit 


In a cable, a broken conductor will not allow electrical energy to flow through it. 




These circuits are also called broken circuits. The circuit is open to the air (which 
looks like a very high impedance). 


Precision 


The statistical spread or variation in a value repeatedly measured, generated, or 
displayed under constant conditions. Also called repeatability. 


Reactance 


A conductor’s opposition to the flow of AC electrical energy through it. All 
conductors have some reactance. Reactance is made up of capacitance and 
inductance. Capacitance is the ability of conductors separated by thin layers if 
insulation (dielectric) to store energy between them. Inductance is the ability of a 
conductor to produce induced voltage when the electrical current through it varies. 
All conductors have some capacitance and inductance, so all conductors have some 
reactance, which means they all have impedance. 


Reflectometer 


An instrument that uses reflections to make measurements. Our reflectometers use 
electrical energy that is reflected back from points along a cable. 


Resistance 


A conductor’s opposition to the flow of DC electrical energy through it. All 
conductors have a certain amount of resistance. Resistance is the low (or zero) 
frequency part of impedance. 


Resolution 


For a given parameter, the smallest increment or change in value that can be 
measured, generated, or displayed. 


Return Loss 


The amount of energy reflected or returned from a cable indicates how much the 
impedance in the system is mismatched. The ratio of the energy sent out by the TDR, 
divided by the energy reflected back, expressed in the logarithmic dB scale, is called 
return loss. 


Rho (p) 


(see Millirho) 


Risetime 


The time it takes a pulse signal to go from 10% to 90% of the change in voltage. 


RMS 


An acronym for Root Mean Squared. RMS is a way of measuring how much 
deviation there is from a known (or desired) waveform. It is also the method used 
to calculate how much power is contained in an AC waveform. 


Sampling Efficiency 


Our instruments make measurements by taking a succession of samples in time and 
displaying them as a waveform with voltage on the vertical scale (up and down) and 



Glossary-4 



1502B MTDR Service Manual 



Glossary 





time along the horizontal scale (across the display). The circuitry that captures and 
holds the samples cannot instantly change from one voltage level to another. It might 
take the circuit several samples to settle in at the new voltage after a rapid change 
in the waveform. How efficiently the circuit moves from one sampled voltage level 
to the next is called sampling efficiency. If the efficiency is too low, the waveforms 
will be smoothed or rounded. If the efficiency is too high (above 100%), the circuit 
will actually move beyond the new voltage level in a phenomenon known as 
overshoot, which becomes an unwanted source of noise in the waveform. 


Series Loss 


Conductors all have some DC resistance to the flow of electrical energy through 
them. The amount of resistance per unit length is usually nearly constant for a cable. 
The energy lost overcoming this series resistance is called series loss. The series loss 
must be compensated for when measuring the return loss or impedance mismatch 
at the far end of long cables. 


Short Circuit 


In a cable, a short circuit is a place where the signal conductor comes into electrical 
contact with the return path or ground conductor. The electrical circuit is actually 
shorter than was intended. Short circuits are caused by worn, leaky, or missing 
insulation. 


Stability 


The change in accuracy of a standard or item of test equipment over an extended 
period of time. Unless otherwise specified, the period of time is assumed to be the 
calibration interval (might also apply to range, resolution, or precision as a function 
of time). The term stability might also be used to denote changes resulting from 
environmental influences, such as temperature, humidity, vibration, and shock. 


TDR 


An acronym for Time-Domain Reflectometer. These instruments are also called 
cable radar. They send out pulses of energy and time the interval to reflections. If 
the velocity of the energy through the cable is known, distances to faults in the cable 
can be displayed or computed. Conversely, the speed that the energy travels through 
a cable of known length can also be computed. The way in which the energy is 
reflected and the amount of the energy reflected indicate the condition of the cable. 


Velocity of Propagation 
(Vp) 


Electrical energy travels at the same speed as light in a vacuum. It travels slower than 
that everywhere else. The speed that it travels in a cable is often expressed as the 
relative velocity of propagation. This value is just a ration of the speed in the cable 
to the speed of light (so it is always a number between 0 and 1). A velocity of 
propagation value of 0.50 indicates that the electrical energy moves through the 
cable at half the speed of light. 


Waveform Averaging 


(see Noise) 



1502B MTDR Service Manual Glossary-5 



Glossary 



Glossary-6 



1502B MTDR Service Manual 



Index 



A 

AC (see Power), ix 
Accessories, 4-2 
Optional, 4-3 
Standard, 4-2 
accessories, standard, 4-2 
Altitude Spec, 3-3 

B 

Battery (see Power) 

Battery Pack Spec, 3-2 
BNC Connector, 4-2 

C 

Cable 

Open, 1-13 
Short, 1-13 
Test Procedure, 1-12 
Distance to Fault, 1-12 
Horizontal Set Reference, 1-21 
Reflection Coefficient, 1-14 
Return Loss, 1-15 
Store Waveform, 1-18 
Vertical Set Reference, 1-23 
View Difference, 1-19 
View Input, 1-17 
View Store, 1-18 
Calibration 

Adjustment Procedure, 6-24 
Case/Shield Removal, 6-25 
Equipment Required, 6-24 
LCD, 6-35 

Metric Instruments, 6-24 
Power Supply, 6-25 
Charging Current, 6-33 
DC Power, 6-30 
Main Board 12 V, 6-29 
Power-Up, 6-25 
Range Check, 6-28 
Voltage Checks, 6-26 
Timebase Compensation, 6-24 
Visual Inspection, 6-25 
Zero Offset, 6-38 
General, 6-1 
Performance Check, 6—1 
Battery Pack, 6-23 
Chart Recorder, 6-23 
Display Module, 6-2 
EL Backlight, 6-3 
LCD, 6-2 

Equipment Required, 6-1 
Front Panel, 6-4 
Menu Access, 6-4 
Presets, 6-4 

Pushbutton Switches, 6-5 
Rotating Controls, 6-5 



Thermistor, 6—7 
Getting Ready, 6-1 
Horizontal Scale, 6-7 
Impedance, 6-34 
Jitter, 6-21 
Metric Default, 6-23 
Metric Instruments, 6-1 
Noise, 6-13 
Offset, 6-12 
Offset/Gain, 6-16 
Pulse Balance, 6-17 
RAM/ROM, 6-16 
Risetime, 6-19 
Sampling Efficiency, 6—15 
Timebase, 6-7 
Vertical Position, 6-12 
Zero Offset, 6-10 
Characteristics 
Electrical, 3-1 
Environmental, 3-3 
Physical, 3-4 

Checks (see Performance Checks) 

Circuit Description 
Display Module 
Block Diagram, 5-29 
Column Driver, 5-33 
Block Diagram, 5-32 
Timing Diagram, 5-35 
Column Driver Interface, 5-38 
Column Drivers, 5-31 
Controller, 5-37 

CPU and Display Memory Timing Diagram, 
5-39 

CPU Interface, 5-38 
EL Backlight, 5-40 
General, 5-29 
ITO Heater, 5-41 
LCD Cell, 5-30 
Memory, 5-37 
Memory Interface, 5-38 
Row Driver, 5-32 
Block Diagram, 5 — 31 
Timing Diagram, 5-34 
Row Driver Interface, 5-37 
Row Drivers, 5-31 
Supply Voltages, 5-33 
SBE Cell, 5-31 
Shift Register, 5-37 
Driver/Sampler, 5-23 
Bridge Bias, 5-24 
General, 5-23 

Power Supply Conditioner, 5-24 
Second Sampler, 5-23 
Trigger Pulse Shapers, 5-24 
Elapsed Time Indicator, 5-22 
Front Panel 

Analog-to-Digital Converter, 5-27 



1502B MTDR Service Manual 



lndex-1 




Index 



Block Diagram, 5-26 

Display Heater, 5-28 

Display Temperature Compensation, 5-28 

EL Backlight, 5-28 

General, 5-25 

Push Button Switches and Latches, 5-25 
Resistive Shaft Encoders, 5-27 
Rotary Binary Switches, 5-27 
Switch Multiplexers, 5-27 
Front-End, 5-23 
Introduction, 5-1 
Option Port Interface 
Block Diagram, 5-11, 5-13 
Buffers, 5-12 
General, 5-10 
Output Latch, 5-12 
Supply Control, 5-11 
Wiring Configuration, 5-12 
Power Supply 
Battery Charger, 5-6 
Block Diagram, 5-4 
DC-to-DC Converter, 5-7 
Deep Discharge Protection, 5-6 
General, 5-4 
Post-Regulator, 5-7 
Pre-Regulator, 5-6 
Primary Circuit, 5-5 
Processor, Block Diagram, 5-8 
Processor System 
Address Decoding, 5-9 
Decoding, 5-10 
Display RAM Space, 5-9 
Enable and Select Signal space, 5-9 
EPROM, 5-9 
General, 5-7 
Interrupt Logic, 5-10 
Memory, 5-9 
Microprocessor, 5-8 
Non-volatile RAM Space, 5-9 
Program Memory, 5-9 
RAM, 5-9 

Pulse Generator/Sampler, Block Diagram, 5-24 
System Block Diagram, 5-2 
Timebase 
Analog, 5-20 
Block Diagram, 5 — 16 
Calibration of Delay Diagram, 5-19 
Control Diagram, 5-17 
Digital, 5-20 
General, 5-15 
Time Delay Diagram, 5-18 
Video Processor 
General, 5-13 

Output Scope Waveform, 5-15 
Summing Amplifier, 5 — 14 
Vertical Position DAC, 5-14 
Video ADC, 5-15 
Video Amplifier, 5-14 
Waveform Accumulation Diagram, 5-3 
Connectors 
BNC - BNC, 4—3 



BNC to Alligator, 4-3 
BNC to Banana, 4-3 
BNC to Binding Post, 4-3 
BNC to F Type, 4-3 
BNC to GR, 4-3 
BNC to Hook Tips, 4-3 
BNC to N Type, 4-3 
BNC to UHF, 4-3 
Controls 

Cable Connector, 1-5 
Distance / Division, 1-6 
Front Panel, 1-4, 1-5 
Horizontal Position, 1-6 
Menu Button, 1-6 
Noise Filter, 1-5 
Power, 1-6 
Store Button, 1-7 
Velocity of Propagation, 1-6 
Vertical Position, 1-6 
Vertical Scale, 1-6 
View Difference Button, 1—6 
View Input Button, 1-6 
View Store Button, 1-6 

D 

Depth Spec, 3-4 
Diagrams 

Component Locator 

Driver/Sampler Board, 9-30 
Front Panel Board, 9-25 
Main Board, 9-15 
Power Supply Board, 9-28 
Exploded Views 
Assemblies, 10-18 
Battery Pack, 10-20 
Cabinet, 10-17 
Frame, 10-18 

Front Panel Controls, 10-18 
Power Supply, 10-19 
General Information, 9—1 
Assembly Numbers, 9-1 
Comp Numbers, 9—2 
Comp Values, 9-2 
Grid Coordinates, 9-1 
Parts Locator, 9-1 
Symbols, 9-1 
Parts Locator 
Front Panel Board, 9-8 
Main Board, 9-4 
Power Fuse Jack, 9-13 
Power Supply, 9-9 
Driver/Sampler Board, 9-11 
Schematics 

Driver/Sampler Board, 9-31 
Front Panel Board 
Pots/EL Lamp, 9-27 
Switches, 9-26 



lndex-2 



1502B MTDR Service Manual 



Index 



Main Board 

Address Decode, 9-16 
Analog Timebase, 9-23-9-24 
Connectors, 9-16 
Digital Timebase, 9-22 
Miscellaneous Analog, 9-20 
Option Port Interface, 9-19 
Processor, 9-17 
Video Processor, 9-21 
Power Fuse Jack, 9-32 
Power Supply Board, 9-29 
Schematic Symbols, 9-3 

E 

Electromagnetic Spec, 3-4 

F 

Features (see Menu) 

Fungus Spec, 3-3 
Fuse, 4—2 
Fuse (see Power) 

H 

Handling, 1-1 
Height Spec, 3-4 
Horizontal Set Reference, 1-21 
Humidity Spec, 3-3 

I 

Indicators, 1-5 
Inspection, xiv 

L 

Loss, 1-16 

M 

Maintenance 

Assembly/Disassembly (see Removal/Replacement) 
Equipment Required, 7-1 
General, 7-1 
Metric Default, 7-13 
Part Removal / Replacement, 7-2 
AC Fuse, 7-2 

Battery, DC Banana Plugs, 7-7 
Case Cover Installation, 7-22 
Control Panel, Watertight Seals, 7-20 
Desiccant Cartridge 
Checking, 7-3 
Rejuvenating, 7-4 
Display Module, Removal, 7-11 
Driver/Sampler Board, Removal, 7—11 
EMI Shield Installation, 7-21 
Front Panel Assembly, Removal, 7-11 
Front Panel Board 
Removal, 7-11 

Removal from Display Module, 7—12 
Fuse Holder, Removal, 7-7 



Main Board 

Elapsed Time Indicator, 7-9 
EPROM Replacement, 7-10 
Lithium Battery, 7-10 
Removing, 7—8 

Option Port Assembly, Removal, 7-14 
Power Cord, Conductor Color Code, 7-7 
Power Cord Receptacle, Removal, 7-6 
Power Supply Board, Removal, 7-6 
Power Supply Module, Removal, 7-5 
Power Transformer, Removal, 7—6 
Remove Case, 7-3 
Remove EMI Shields, 7-3 
Sealing Materials, 7-20 
Voltage Selector, Removal, 7-7 
Preventive, 7—1 
Cleaning, 7-1 
Lubrication, 7-2 
Recalibration, 7-2 
Visual Inspection, 7-2 
Troubleshooting, 7-14 
Flow Chart, 7-14 
Waveforms, 7-15 
When All Else Fails, 7-20 
Manual Changes, xiii 
Maximum Hold, 1-25 
Menu, 1-7, 1-25 
Cables, 1-7 
Diagnostics, 1-8 
Chart Recorder, 1-9 
Head Alignment, 1—9 
LCD Chart, 1-9 
Front Panel, 1-8 
LCD, 1-9 
Alignment, 1 — 9 
Contrast, 1-9 
Drive Test, 1-9 
Response Time, 1-9 
Service, 1-8 
Noise, 1-8 
Offset / Gain, 1-8 
RAM /ROM, 1-8 
Sampling Efficiency, 1-8 
Timebase, 1-8 
Display Contrast, 1-10 
Impedance, 1-7 
Main, 1-7 

Maximum Hold, 1-25 
Option Port, 1-9 
Debugging, 1-9 
Diagnostic, 1-9 
Timing, 1-9 
Pulse, 1-26 
Setup, 1-7 

Acquisition Control, 1-7 
Backlight, 1-8 
Distance / Division, 1-8 
Maximum Hold, 1-7 
Pulse, 1-7 



1502B MTDR Service Manual 



lndex-3 



Index 



Single Sweep, 1-7 
Vertical Scale, 1-8 
Single Sweep, 1-27 
Velocity of Propagation, 1-7 
View Stored Waveform, 1-9 

N 

Noise (see also Controls), 1-5 

O 

Ohms-at-Cursor, 1-17 
Open, 1-13 
Option Port Cover, 4-2 
Options, xiii, 4-1 
Battery Pack (03), 4-1 
Chart Recorder (04), 4-1 
Chart Recorder (07), 4-2 
Metric Default (05), 4-1 
Power Cords, 4-2 

P 

Performance Checks, 2—1 
Aberrations, 2-6 
Conclusions, 2—10 
Equipment Required, 2-1 
Horizontal Scale, 2-2 
Jitter, 2-9 
Noise, 2-5 
Offset /Gain, 2-6 
Risetime, 2-8 
Sampling Efficiency, 2—6 
Set Up, 2—2 
Vertical Position, 2—4 
Pouch, 4-2 
Power 
AC, xiv 

AC Receptacle, 1-1 
Battery, xiii, xiv 
Low Indicator, 1-3 
Remove / Replace, 4-1 
Battery Pack 
Care of, 1-2 
Charging, 1-2 
Cords, 4-2 
Safety, ix 
Fuse, x, 1 — 1 
Fuse Rating, 1-2 
Requirements, xiv 
Safety, xi 
Source, xiii 
Voltage Rating, 1-2 
Voltage Selector, 1-1 
Voltages, 1-1 
Product Description, xv 
Pulse, 1-26 

R 

References, xiii 
Reflection Coefficient, 1-14 



Repacking, xiv 
Replaceable Parts 
Electrical 
Assemblies, 8-6 
Driver/Sampler Board, 8-30 
Front Panel Board, 8-21 
Main Board, 8-8 
Parts Ordering Information, 8-1 
Abbreviations, 8-1 
Comp Numbers, 8-1 
Descriptions, 8-2 
List of Assemblies, 8-1 
Mfg. Number, 8-2 
Mfr. Codes, 8-1, 8-2, 8-3 
Serial Number, 8-2 
Tek Number, 8-2 
Power Supply, 8-25 
Wire Assemblies, 8 — 36 
Mechanical 
Abbreviations, 10—2 
Chassis Parts, 10-2 
Column Descriptions, 10-2 
Lists 

Battery Pack, 10-15 
Case, 10-5 
Frame, 10-8 
Front Panel, 10-8 
Power Supply, 10-13 
Mfr. Code, 10-2, 10-3 
Parts Ordering Information, 10-1 
Using the Lists, 10-1 
Return Loss, 1-15, 1-16 

S 

Safety 
Covers, x 

Explosive Atmosphere, x 
Grounding, x 
Symbols, ix 
Terminology, ix 
Safety Summary, xi 
Salt Atmosphere Spec, 3-3 
Sand and Dust Spec, 3-3 
Scale (see Controls) 

Service Manual, 4-3 
Ship Carton Strength, xv 
Shock Spec, 3-3 
Short, 1 — 13 
Single Sweep, 1-27 
Slide Rule, 4-2 
Specifications, 3-1 
Electrical, 3-1 
Environmental, 3-3 
Physical, 3-4 
Store the Waveform, 1-18 

T 

Temperature, Low, 1-4 
Terminator, 4-2 



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1502B MTDR Service Manual 



Index 



U 

Unpacking, xiv 

V 

Velocity of Propagation, 1-10 
Table of Types, 1-10 
Unknown Vp, 1-11 

Velocity of Propagation (See also Controls), 1-6 
Vertical Set Reference, 1-23 
Vibration Spec, 3-3 



View Difference, 1-19 
View Input, 1-17 
View Store, 1-18 
Voltage (see Power) 

Voltage Spec, 3-2 

Vp (see Velocity of Propagation) 

W 

Water Resistance Spec, 3-3 
Waveform Storage, 1-18 
Weight Spec, 3-4 



1502B MTDR Service Manual 



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Index 



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1502B MTDR Service Manual