Publisher/Editor: K. D. Cheek, Sr. aka "Dr. Rigormortis"
V2H1: January, 1992
THE WORLD SCANNER REPORT
A Journal of VHF-UHF Scanner Technology S Engineering
Published at: COMMtronics Engineering; PO BOX 262478; San Diego, CA 92196 Copyright (c) 1991-2 <A11 Rights Reserved) $4.00
THE YEAR OF THE INTERFACE - 1992
Wow. is this ever going to be the year of the interface!
Since last issue, I built and tested the RW Systems Model
SC-2 Interface Kit and was spellbound by its simplicity
and ease of operation! It worked perfectly the first
time power was applied; no stupid mistakes or developer's
oversights to contend with as we Hackers often have to
face! Ecstasy had hardly subsided when I went for broke
to test Datametrics, Inc. Computer Aided Scanning system.
Once again, I was launched into the stratosphere, though
not for the same reasons as RW Systems’s interface. The
two are as different as night and day; neither comes out
as a clear winner; and either one is capable of opening
up a whole new dimension to your scanning. Read about
each one elsewhere in this issue.
Roll your own Scanner/Computer Interface? Sure, why not?
You'll not be able to copy Datametrics and RW Systems
interfaces for two reasons: (1) each is a proprietary
design which would be dishonest to copy in the first
place, and (2) the developers included one or more hard-
programmed chips in their designs to thwart the efforts
of would-be copy cats. However, "Professor Peabody" and
his able assistant "Sherman" have spent the last three
months working up a real whopper of a do-it-yourself
interface that we’ll serialize over this and the next
couple of issues. The "HSR" may offer more do-it-
yourself interfaces in the future. The bottom line is
this: no matter your experience, ability or inclination,
we will present or introduce a scanner/computer interface
that will be just about right for your needs and desires.
Rumors persist that Radio Shack is going to introduce a
scanner with a computer interface. I have no reason to
bet on it yet, but it's probably a matter of time.
SCHEMATIC DIAGRAM FROM LAST MONTH'S
SERIAL DATA INTERCEPTOR/DECODER
Space wasn't available last month for the schematic
diagram of HB Tech’s Serial Data Interceptor/Decoder
described on page 2. That circuit and article was aimed
at technicians and engineers who need to understand the
data flow between the PRO-2024/5/6's CPU and the LCD
Display Driver chip. This is not a project for casual
hobbyists, but it will save the thousands of dollars'
cost of a logic analyzer which is otherwise needed to
intercept and decode the serial data flow out of the
scanner’s CPU. The schematic diagram that wasn't given
last month is on page 8 thi-s month with no further ado.
It’s a cost effective tool developed by HB Tech in their
design of a scanner/computer interface. If you have any
questions about the circuit or how it works, I will be
happy to forward your inquiry to HB Technologies.
WHAT’S UP FOR 1992?
1992 is the Year of the Interface but it doesn't mean
that scanner/computer interfaces are all you're going to
see here in the "tfSR". Far from it. Let me give you a
sneak peek at what might lay ahead.
A CELLULAR PHONE/TRUNKED CALL FOLLOWER just might be
around the corner. Know how you can be listening to a
hot 'n spicy cell phone or SMR trunked conversation one
minute only to find it gone the next? Well, several
companies have come out with data readers that show what
frequency to which that cellular phone conversation was
handed off. In some instances, these gizmos can actually
change the receiver's frequency to follow suit. This
type of equipment was designed for law enforcement
agencies with a cost to match at $2500 and up. Comes now
an interesting little digital circuit that can do pretty
much the same thing at a cost of under $200. A small
circuit board goes between the EXTERNAL SPEAKER jack of
your scanner and a serial port of your computer. The
circuit's logic pretty much does everything for you,
including print an interpretation of the control data on
the computer's screen. I understand that it will also
control certain AOR scanners to follow cellular phone
calls as they are handed off from one cell to another!
This unit is now under evaluation and will be discussed
in*future issues. If interested, study up on cellular
and trunked SMR radio systems so you can be ready. I say
"trunked systems", too, because self-respecting and
law-abiding scannists don't bother to monitor cellular
conversations, but there's every reason and lawful right
to monitor the 800 MHz trunked systems, and this unit
just might work for that purpose, too!
Continuous Tone Coded Squelch Systems (CTCSS) are nothing
new but scannists are becoming more and more interested
in applying CTCSS-decode capability to their scanners.
CTCSS is a pretty slick concept that can add a new
dimension to the capabilities of your monitoring post.
We will rehash the CTCSS mods given in Vol-2 of my
SCANNER MODIFICATION HANDBOOK and cut some new turf in
this interesting side action of scanning! Read my Vol-2
again and/or contact the following company for info on
their CTCSS products if you want to be prepared for
what's to come:
COMMUNICATIONS SPECIALISTS ,INC.
426 WEST TAFT AVENUE
ORANGE, CA 92665.4296
800-854-0547 & 714-998-3021
A REMOTE CONTROLLER FOR THE PRO-2004/5/6 & other scanners
has long been on the hobbyist's want list. A basic
version of my Remote Controller appeared in my column of
a recent issue of MONITORING TIMES and will appear again
here in a future issue for those who don’t get MT. "Prof
Peabody" has a full function Remote Controller that will
be presented in a coming issue. The thing about Remote
Controllers is that you can't parallel a bundle of wires
from the scanner's keyboard to a remote switch unit. The
scanner's CPU will lock up if it's done like that. We
will show you the right way later this year.
What else? To tell all would take the fun and surprise
out of it, but still on our print schedule after the bugs
are worked out include an SSB Adaptor for the PRO-2004/5
& /6 and certain other scanners; more shortwave receiver
mods; back to radio basics (hints, tips, kinks, etc); AND
we're saving plenty of room for new products, techniques
and ideas which will appear from time to time. Space is
also reserved for what YOU want that we might have over¬
looked. This is one special, unique characteristic of the
"t/SR": we're open to new ideas; we're flexible; and we
can turn on a dime to suit yours and our needs.
We got a deal on that "cheap" IBM computer I requested
last month, thanks to Mike Schriber, who found a bargain
of a 640-k XT with a 40-Mb hard drive. Obviously, the XT
is more of a learning tool but I've learned enough to get
serious about a more powerful computer with laser printer
capabilities to see the "WSR" into the end of 1992. All
things in good time, but the wheels are in motion.
+ Two-way operation: programs frequencies into the
scanner; collects data from the scanner.
+ Four modes of operation are available: (1) Downloads
(programs) 1 to 400 frequencies at a time into the
scanner; [A 400-ch download takes about 9-minutes, max]
(2) A limited activity log uploads a record of active
frequencies from either the SCAN or SEARCH mode to the
computer's review buffer; [you can transfer this record
to a data base!] (3) Quickly uploads contents of the
scanner's memory, 1 to 400 chan, into the computer's
buffer memory. [You can transfer this record to a data
base!] (4) Manually change channels to be monitored
from the keyboard.
+ Easy to master and use; very little to memorize.
+ Programming the scanner via the Interface is similar to
sending an ASCII file to a BBS.
As an example, a partial file to be sent could be
configured something like this:
>mi1itary air freq
>amateur radio repeater
>amateur radio net
Also in the plan is to set up a computer bulletin board
service (BBS) to serve your needs for speedy replies,
info and answers to your questions. For this, we need a
third phone line which is proving difficult to get at
this time, but we hope to overcome that obstacle sooner
than later. At worst case, we'll set up a part time BBS
for the evening and night hours to serve you better.
Watch coming issues for an announcement of the phone
number and schedule.
Where precedes the starting channel (001) to be
programmed; precedes the 8-digit frequency to be
programmed; . precedes a frequency to be programmed and
LOCKED OUT. Therefore, with minimal manipulation, your
data base of scanner frequencies can be used to program
+ Ignores all ASCII text except numbers preceded by one
these three characters: @ * A Therefore
commentary & text in the data base are irrelevant.
SCANNER/COMPUTER INTERFACES AT LAST! A Review of Two + Professional (Mil-Spec appearing) printed circuit board
with a Solid and thorough electronic design!
RW SYSTEMS MODEL SC-2
I am pleased to offer an evaluation of a most effective
and potent computer interface for the PRO-2004, PRO-2005
& PRO-2006 scanners. First, here are the SC-2's PLUSes:
+ Works with virtually any computer that has a serial
port, RS—232 compatible; i.e., universal.
+ Special software not required; works with most any
standard telecom (modem) program, but a modem is not
used. Four wires in a cable 25-ft long or less connect
between the computer's serial port (TxD, RxD, RTS and
ground) to the interface. The cable is not difficult
to make up if you don’t have one.
+ Interface is compatible with most mods, but see below.
+ Does not interfere with normal use of scanner.
+ 1-yr warranty on parts & proper operation
Continuing to tell it like it is:
Available only as a kit excluding cable and wiring.
Requires 1-2 hours to assemble the PCB with its six 1C
chips and handful of parts. Requires another 2-4 hours
to install in scanner. Another hour may be needed to
fabricate the cable between the computer & interface.
Documentation & directions are adequate, but not great.
’THE WORLD SCANNER REPORT" (c) 1991-2; V2N1
- January, 1992; Page 2
- With exception of LOCKOUT, the RW Systems interface
does not accept custom programming such as MODE
(AM/NFM/WFM), DELAY, PRiority etc. These custom
program functions must be manually set as needed.
- The interface draws about 225-ma from the scanner's
AC/DC power supply which increases heat accumulation
within the scanner. I recommend powering the scanner
with a +12v @ 1-amp external power supply anyway;
otherwise, there could be long term problems caused by
the extra heat in the scanner, especially if other mods
have also been done. An external DC power supply will
nul 1 ifv this potential liability!
- The Interface has a custom programmed microprocessor
chip and two PAL chips. This means that replacement/
repair parts might not be available if the supplier
were ever to elope to Mexico with his secretary.
- The interface might not be compatible with speed
modifications where the Clock Resonator has been
replaced with a crystal. (For sure, in my PRO-2004.)
- Some "of the variables in your telecom program may have
to be "played with" such as Tx Line Delay (.4-sec), but
this results from the slowness of the scanner; not a
fault in the Interface.
- For the PRO-2004, -2005 & -2006 only; no others
The SC-2 Interface Kit is available for $100.00 from: RW
SYSTEMS; PO BOX 910043; SAN DIEGO, CA 92191. When you
inquire or order, please mention that you heard about the
Interface from Bill Cheek via the "WSR"!
In conclusion, I like the SC-2 Interface despite any real
or imagined shortcomings. I highly recommend it to those
scannists who are technically inclined and those who are
patient & methodical in their work. If you are not able
to build and install it yourself, I can do it for you.
The SC-2 Interface kit is also available from COMMtronics
Engineering for the same price as from the developer.
DATAMETRICS. INC. COMPUTER AIDED SCANNING SYSTEM
There is a night & day difference between RW Systems
interface and that from Datametrics! So different, in
fact, that this one just might be for you if you see some
shortcomings in RW Systems' unit. As before, here's the
scoop just exactly the way it is:
+ Professional preassembled/finished printed circuit
board; nothing to assemble or fabricate; only a cable
is required; commonly available.
+ Exceptionally easy to install; (PRO-2005/6); no holes
to drill; no soldering; no cutting; no fuss, muss or
mess. The interface PCB plugs into CN-501, an existing
connector. Two wires from the interface clip to easily
identified spots on the main board of the scanner. A
ribbon cable from the interface is routed out the rear
of the scanner; the plastic case goes back on over the
ribbon cable at the end of which is a DB-25 connector
for the cable that goes to the computer's parallel
output port. (LPT1, LPT2, etc). Installation time
should not require over 5-10 minutes!
+ Software permits user to control the scanner from the
computer keyboard for SCAN, SEARCH & MANUAL functions.
SCAN channels and SEARCH ranges are easily defined from
the computer keyboard.
+ Software contains an easy-to-use data base manager for
frequency management; virtually any number of files of
1 to 1000 channels per file can be generated for
various program needs.
+ Two-way operation: programs frequencies into the
scanner; collects data from the scanner, (see below)
+ Downloads (programs) up to 400-channels at a time into
the scanner in less than 10-mi ns.
+ External data base frequency files can be imported into
the Datametrics data base.
+ Menu-driven software includes full monitoring display,
digital spectrum display and system editor. (See Fig-1)
+ Comprehensive, professionally prepared manual includes
detailed instructions, screen displays and references.
+ Estab1ished company experienced with interfaces for
radios; well known for their control program/interface
for ICOM R-71A & R-7000 receivers.
+ Does not interfere with normal use of scanner.
+ 30-day return privileges if not satisfied.
Continuing to tell it like it is:
- Works ONLY with an IBM PC/XT/AT/clone w/360-k RAM (or
640-k for full channel capacity).
- Very slow SCAN & SEARCH speeds when under software
control, i.e, about 1-2 channels or steps per second.
- Does not actually "control” or "read" most of the
scanner's operations; instead software emulates control
of the scanner; places it in the PRGM mode and then
performs various programmable functions from software.
Hard to describe and not materially important except
that scanner sends no information back to the computer
other than SQUELCH breaks. The software uses its own
memory and the SQUELCH break information to pace the
scanner in software-controlled SCAN, SEARCH & MANUAL
emulations. The effect is reduced speed of operations.
- Software intensiveness means more to learn and more
"behind the scenes" effort to achieve mastery and
simplicity of operation. No problem with time.
"THE WORLD SCANNER REPORT" (c) 1991-2; V2N1 - January, 1992; Page 3
- Supported by Datametrics to work ONLY with the PRO-2006
(However, there is no functional reason why it can't
also be installed and operate as specified with the
PRO-2005. Should also work with the PRO-2004 except
that installation will be more complicated due to
mechanical differences of the PRO-2004.
- Not inexpensive
The SC-2 Interface Kit is available for $350.00 from:
Datametrics, Inc.; 2575 S. Bayshore Dr, Ste 8A; Coconut
Grove, FL 33133. When you inquire or order, please
mention that you heard about the Computer Aided Scanning
System from Bill Cheek via the "ffSR"'.
Fig 1 - Frequency Scan Screen
SCftf! FREUUEHCV FILE
Filename : C:\SCflf1\PROGRfiH\HOf1ITOH.FHQ
' '' Parameters ““ Status Indicators
Longest Duration : 93 Frequency : 259.7000
H Ini nun Duration : 0.9GO Signal : On
Delay : Z Tine : 16:05:12
Autolog (OrSfD) : 0 Monitor Tine : 5.39
Bounceback : 0 Scan rate : 2.
34.8100 135.5750 165.9580 469.9125
n - HiLf rz - codes ra - siitings m - lockout rs - roust
re - resent rr - ustlw re - mia n - ten ri» - wit
DO-IT-YOURSELF FEATURE PRESENTATION
::: THE FATMAN COMPUTER INTERFACE ::: Part 1
By: "Professor Peabody"
Greetings Fellow Scanner Fans! Here's another project
for your hacking addictions: a computer interface with a
remote control keyboard for the PRO-2004/5/6 scanners and
which might be adaptable to other scanners that have a
keyboard similar to the Radio Shack models.
Before we get into the juicy meat of this project, let's
discuss computer interfaces and what they can do. A top-
of-the-line functional interface will have all controls
and functions of the scanner visually simulated on the
computer screen to make you feel right at home operating
the scanner from a computer. The interface should monitor
all controls, functions, events and activities that occur
in the scanner; everything that happens should generate
data to be passed back to the computer. There should also
be a menu of user controls to select or reject specific
data that gets passed to the computer. In summary, the
ideal interface will be an extension of the scanner's
controls and operating panel for computer supervision and
rule over everything that happens in the scanner. This
describes a very sophisticated interface that's totally
worthless without corresponding sophisticated software.
Big bucks and a steep learning curve are prerequisite
before you can even flip a switch.
Questions: would you really use all those functions and
options from a computer keyboard? Do you care how many
times a particular frequency is active over a period of
time? What is the use of a "map" of the birdies in your
radio? How about a spectrum chart of all active freqs in
a range? Heck, I could go for all this stuff but on a
limited budget, it’s tough to have it all.
I like the Datametrics system and highly recommend it to
those who don't have the time or expertise for technical
work. It also comes with recommendations for those who
perform radio commo traffic studies & analyses on limited
budgets where scanners are a part of the job. It is
capable of logging and compiling some very impressive
charts, bargraphs, and reports on commo activities in
your area. In this sense, the Datametrics system can be
called a "communications data logger." Operating it
resembles being in the cockpit of an aircraft. It's fun!
CONCLUSION & SUMMARY: I just love products like those
from RW Systems and Datametrics which make my job easy!
I like them both, but am hard pressed to choose a
favorite; they're just too diverse and different, like a
pickup truck and a touring car. The only difference in
this case is that you don't want BOTH; one or the other
will do nicely. But then where one may not be right for
you, the other one just could be perfect! In any event,
either one drops 400-channels into your PRO-2004/5/6 with
minimal drudgery and to my way of thinking, that's the
most important function of an interface. "Professor
Peabody" now tells you what he thinks.
One justification for the big bucks is the feature of
data transfer to the computer for temporary or long term
storage. Some mods like the Search & Store Module can do
little more than store a bunch of active frequencies in
the scanner's permanent memory. There's no good way to
process that info without an interface, short of writing
it all down and manually entering it into the computer.
It becomes a matter of WHAT we want versus HOW MUCH we
are willing to pay. It is not a high priority for my
computer to operate and log data from the scanner. It
could be fun; don't get me wrong, but is not important.
Not everyone wants all the same finer things in Life, but
we all want to breathe and eat for starters. The point
I'm about to make for interfaces is that we all WANT to
have the computer program the scanner for us! Anything
else that the interface can do is so much icing on the
cake and to each, his own. The vital thing for me is for
the interface to permit a computer to program the 6,400
channels in my PRO-2005. You see, twice now, I have
accidentally shorted out the +5v Memory Retention Battery
circuit which wiped out the entire sixteen Blocks of
memory in each instance! I'm pretty good at programming
the keyboard BUT it takes better than an hour to do one
"THE WORLD SCANNER REPORT" (c) 1991-2; V2N1 - January, 1992; Page 4
400 channel Block. After that I'm wiped out mentally
from intense error correcting and concentrating. Then it
takes 15 more nights of programming at one Block a night.
Have you thought about doing Doc's 64-Slock, 25,600-Chan
Extended Memory? I have, but the idea of hand programming
all that memory only to lose it by a stupid mistake once
gave me a violent rash of hives. Now I will reconsider
because that data can be slam-dunked into memory in about
2-hrs. Huh? Well, I am about to show you a mod that's
on a par with Doc’s multi-thousand channel memory mods
and more exciting. It's inexpensive and does not require
any custom programmed microprocessors, PALS or PROMS.
Reconfiguring for extra functions is a cinch but I’m
getting way ahead of myself. Here's the deal:
Necessity, the mother of invention, with a slim budget
for a prime mover, drove me to design a thrifty interface
to program my scanner for me. I only recently got into
computers, so I didn't want any weird or sophisticated
software that would take forever and a month of Sundays
to learn how to use. Eureka! My Fatman Interface might
cost upwards of 75 bucks if you bought everything from
scratch at full retail price, but depending on what's in
your junkbox, the cost could be a lot less. With my
Fatman Scanner/Computer Interface, you can load up 400
channels of error-free frequencies, complete with DELAY,
LOCKOUT and desired MODE settings in under six minutes!
An Overview of the Fatman
Ok, we're eating up space and there's a long way to go.
so here's an overview of the project, followed by a parts
list, resource list and a schematic for those who want to
get started right away. We'll conclude the Fatman next
month with a verbal wrap up, alignment and operating
procedures. This project is a hackers delight so use
care in its construction and be neat. It pays off.
There are 5 unique parts to this project, one of them
optional: Remote Controller Keypad. The remote keypad
and interface were designed for complementary operation
because some parts for one are common to the other. Why
a remote keypad? Well, obviously you wouldn't want to
program your scanner from across the room but how about
just operating it in total comfort while sitting in your
stratolounger, all kicked back? Sometimes the best place
to put your scanner isn't always where you would like to
operate it. And then some of us have clubs for fingers
that don’t fit the tiny buttons on the keyboard. The
Remote Controller keyboard can be made as big as you like
with plenty of space between the keys. So the Remote
unit has a value, but leave it out if you don't want it.
The five parts of this project are:
#1 Keyboard Interface; simple & easy
#2 Computer Interface; hairy, but fun
#3 Code Converter; tedious but rewarding
#4 Software (don't panic; just your data base)
#5 Remote Keypad (optional)
The Computer Interface connects to the computer's printer
port instead of an RS-232 serial port. This expels the
need for a telecom program; a regular database program
will "print" data to the interface and fool the computer
into thinking it's feeding a printer. The database thinks
it's sending frequency records to a printer but actually
only ASCII codes go to the interface and code converter
which translates the ASCII inputs to coded outputs needed
by the keyboard interface to simulate scanner keypresses
during programming. My FATMAN is used with an IBM clone
machine but it can probably work with any machine that
sends ASCII characters to a printer.
Only one small mod is done to the scanner; the Keyboard
Interface and a DB-9 connector to accept a cable from the
FatMan Computer Interface which can be in a project box
of your choosing and budget and located anywhere between
the computer and the scanner. The printer cable from
your computer's parallel port connects to the input of
the FATMAN. You can use a printer A-B switch if you will
be programming and printing a lot; otherwise moving the
printer cable as needed will be fine. An additional
benefit of the interface is that the database program can
print a paper record of what's in the scanner's memory.
Additions and changes can be pencilled on the printout;
entered back into the database; then in a relative flash,
painlessly loaded into the scanner. You can nurse on a
can of your favorite beverage and watch the blinking LEDs
on the interface. I am an LED freak and went wild with
them but they were necessary for testing and debugging.
If you want to save space and parts, LEDs can be omitted
but they add to the show when you invite friends over to
see your latest toy. The light show is impressive!!
Some of the CMOS chips may not be available locally, but
if you use 1C sockets, you can start wiring the circuits
while you wait for the big brown delivery truck. The DB-9
connector was installed on the rear panel of the scanner
just above the BNC connector. Admittedly, the drilling
and reaming of the hole in the chassis was a job but once
done, the hard part was over. The rest is fun. Of course,
the DB-9 connector and a short pigtail can just hang out
the back of the radio from a round hole drilled in the
chassis. This same connector is also the hookup point
for the full function Remote Controller.
The Keyboard Interface must go inside the scanner and as
close to the Keyboard connector as possible. Use a Radio
Shack experimenter board, cut to size, small as possible.
The thirteen output wires of the Keyboard Interface are
easily connected to the scanner, but the method differs
between the PRO-2004 and the PRO-2005/6 as shown below.
The 13 wires from the Keyboard Interface to the scanner’s
keyboard MUST be as short as possible.
PRO-2005/5 ONLY: To attach the circuit to the scanner's
keyboard connector (CN-501) in the PRO-2005/6, cut in
half a 28 pin wirewrap socket so you have two separate 14
"THE WORLD SCANNER REPORT" (c) 1991-2; V2N1 - January, 1992; Page 5
pin rows. Save one half for a spare. Pull out one pin
of the other half to leave a row of 13 pins. Insert this
row of pins into the keyboard connector, CN-501, by
pushing down and inward on the connector pins with the
interface pins. (The pin of CN-501 closest to the metal
chassis side wall is Pin 1. Pin 13 is at the opposite
end of that row.) Then solder the 13 wires from the
Keyboard Interface onto the 13 exposed pins. This is a
handy, non-invasive way to tie into the keyboard matrix.
PRO-2004 ONLY: The 13 wires from the Keyboard Interface
must be soldered to the row of visible and easily
accessed 13 solder spots on the back side of the
scanner's keyboard. The BLACK wire on end of the row is
Pin 13, so the opposite end is Pin 1. In lieu of this,
you could follow that wire bundle up to where it connects
to the Logic/CPU Board, PC-3, and devise some way of
slipping a custom connector into the exposed holes of
CN-502. These holes are non-standard spaced at about 2mm
apart, so you're on you're own for a fit at CN-502.
Build the Computer Interface into a project box for best
results. It need not and really should not go inside the
scanner because of its size. You'll need room in the
scanner for other mods from time to time. Special
considerations are not needed for this part of the
project, but if I were you, I'd do your chip layout and
wire planning on paper first. You'll have to use point-
to-point wiring, so make it easy on yourself. There will
be two trimmer potentiometers so put them where they can
easily be accessed later for alignment. You can go hog
wild with the LEDs or not as you see fit. Perhaps the
best advice I can give here is to use DB-9 and DB-25
connectors for output and input, respectively. Locate
these chassis-type connectors on the rear of the project
box for out of sight, out of mind results. If you don't
want to bother with connectors, you can run permanently
wired 9-conductor and 25-conductor shielded cables out
the rear of the box with suitable connectors on the ends
of each cable, DB-9 to the scanner and DB-25 to the
printer port of your computer.
A note on power consumption; all 1C chips are CMOS, so
the current drain is very low. With no LEDs turned on I
measured 1 ma of current. With the LEDs enabled, it drew
25 ma which is still miserly. I am very aware of the
limitations of the onboard power supply but this project
can still be easily powered from the radio. An external
supply can be used but it must be +5 volts only. The
pulse levels between the computer and radio must be.5v.
The cable to the computer can be flat ribbon or bundled
as shielded 25-conductor. The cable to the scanner
should be shielded 9-conductor. Radio Shack used to have
excellent 9 & 25 cond cables, 278-775 & 278-776, but
these have been discontinued and stocks may be sold out
by now. Shielded cables are highly recommended for
obvious reasons. The length of each cable should be 5-ft
or less, but a little longer will probably be ok.
This is a ROM, Read Only Memory. You program it yourself
so it's actually a PROM. Ordinary switching diodes are
used to set up the program. You don't even have to know
what you’re doing if you follow the schematic diagram.
The PROM or code converter is an 80 address by 5 bit
memory. The lower 32 addresses are not used so I left
out the chips but most of the upper 48 addresses are used
to output codes. I'll explain the technology of this
next month in the wrapup, so just build it according to
the diagram for now and include space for it in the
project box that will also house the Computer Interface.
The necessary software can be an ordinary database or
even a word processor program. Any program that can send
an ASCII file to a printer should work. I use a shareware
database called FILE EXPRESS that's great for beginners
but I will assume that you know how to use your database
and how to print files. Next month, you'll learn how to
operate the Fatman by "printing" a frequency file to it.
FATMAN PARTS LIST
SYMB QUAN DESCRIPTION
Keyboard Interface Primary
U1,2 2 74HC4051 8 channel analog multiplexer
R1-6 6 Resistors, 10-k, 1/4-watt
C1-8 8 Capacitors, 0.1-uF, monolythic or tantalum
D1-8 8 Silicon Switch Diodes; 1N4148 or 1N914
J1 1 DB-9 Connector; female; RS #276-1538
PC 1 Multipurpose board; RS #276-150
PI 1 28-pin Wirewrap 1C Socket; RS #276-1983
Computer Interface Primary
U1 1 74HC374 Octal D-Type Flip Flop
U2 * See under Code Converter below
U3 1 74HC244 Octal Buffer
U4,5 2 74HC123 Dual One Shot Multivibrator
U10-12 3 74HC04 Hex Inverter
U8 1 74HC08 Quad AND Gate
U6,7 2 74HC32 Quad OR Gate
U9 1 74HC4066 CMOS Switch
VR1,2 2 Trimmer Pot; 500-k 10 turn precision
R1-16 16 Resistors, 47-k, 1/4-watt
R17,18 2 Resistors, 10-k, 1/4-watt
R19-34 16 Resistors, 1-k, 1/4-watt
Cl,2 2 Capacitors, 0.001-uF disk
C3 1 Capacitor, 1.0-uF, tantalum
C4 1 Capacitor, 2.2-uF, tantalum
SI 1 Switch, toggle; SPST
J1 1 DB-25 Connector; female; RS #276-1548
J2 1 DB-9 Connector; female; RS #276-1538
LEDs 15 Light Emitting Diodes, your choice
"THE WORLD SCANNER REPORT" (c) 1991-2; V2N1 - January, 1992; Page 6
Cods Converter (U-2, in Computer Interface above)
U2d 1 74HC138 3 to 8 line Decoder
U2a-c 3 74HC4514 4 to 16 Decoder with latch
D1-44 44 1N4148 or 1N914 signal diodes
Cl 1 Capacitor, 0.1-uF, monolythic or tantalum
By: William R. Young
74HC148 Priority Encoder
As a charter subscriber, I'm learning a lot from WSR and
am not so reluctant to dig into the radio gear as I have
been. I've used a PRO-26, 4-ch crystal controlled hand¬
held for several years, and there were some things that
needed a change; the DELAY (not needed), the SCAN rate,
fie/nora. /rey/wa oj/u. and the lengthy time it takes to charge the batteries.
as ptGS6A/rel> /A/
A combination of R66 and C64 control the DELAY time. I
74HC20 Dual 4 input NAND gate oP . '^-^^'removed C66, which eliminated the DELAY; it also caused
74HC32 Quad 2 input OR gate Hut />cuo-s vjuro the MANUAL channel selection to be unstable. Instead of
74HC86 Quad Exclusive OR gate th* / m sy£o*ti> the 1 -2-3-4 sequence, selection was random. A 4.7-uf
Switches; push button, n.o. capacitor in place of C64 enabled the MANUAL selection to
Resistors, 47-k, 1/4-watts co~/>vre *f .zv/S4«*2.work with no noticeable delay in the SCAN mode.
Resistor, 1-k, 1/4-watt T *%%
Replacement of C63 with a .1-uf tantalum capacitor caused
an almost 5-fold increase in the scan rate. Replacement
of R70 with a 33 ohm 1/4 watt resistor doubled the charge
rate of the NiCad batteries. I’ve used the mod'd scanner
for several days now and it works great. Keep up the good
work with WSR! [Ed Note: Thank YOU on both counts!]
Capacitor, 0.1-uF, monolythic or tantalum
Light Emitting Diode, choice
ANTENNA & PREAMPLIFIER TESTS
By: Bill Bowers
I tested some antennas and preamps. The purpose of the
test was to find the most effective omni-directional
antenna and preamp for my location. I am in a rural
region about 50 miles from any transmitter. Local police,
Highway Patrol and sheriff offices are located in all
directions around me so I needed an omni-directional
antenna, and overload was not a factor!
I COM AH-7000 PRESSLER ARA-900 AUSTIN'S "THE FERRET"
IDC-WBA-1500 WI-COMM L-A75M
AUSTIN-FERRET preamp RADIO SHACK #15-1117 coax amp
I mounted two antennas on opposite ends of the garage on
10' roof mount poles and ran equal lengths of Bel den 9913
coax to a DALWA-CS201 two-position antenna switch. Then
I searched for a signal on one antenna, and switched back
& forth for comparisons. This was done in 50, 150, 450 &
800-900 MHz ranges. This procedure was repeated for many
combinations. All antennas and preamps were good in the
bands up through 450 MHz but in the 800-900 MHz range,
there was a clear winner. The best combination for the
800-900 MHz range for my location was the ICOM AH-7000
with the WI-COMM L-A75 preamp.
After the winner was determined, I repeated the tests and
compared it to all other set-ups. In many cases, there
were weak signals in the 800-900 MHz range found with the
AH-7000/L-A75 that when switched to any other combination
produced no readable signal at all. P.S. Anyone want to
buy an ARA-900 or Austin-Ferret CHEAP?!
ED NOTE: Thank you, Bill. Your tests were very scientific
and proper, especially for the hobby scene. Now keep an
eye out for the J.l.tt. M-75 & M-100 preamps. These two
are superb and might beat the WI-COMtl hands down!
NEW HANDHELD ICOM R-1 HAS FLAWS
You'd think that a whopper product from the likes of ICOM
would be defect-free, but the newly introduced R-1 DC-to-
Daylight Handheld Receiver has some sort of a bug that
resembles image interference, and which shows itself as
two clones of the desired signal at 150 KHz on either
side of the desired signal. This might not be a problem
in the MANUAL or SCAN modes because you'd simply not run
across those "images" unless you programmed them. It can
render the SEARCH mode effectively useless, however! If
this problem is as widespread as it seems to be, I can't
understand why ICOM released the R-1. In any event, a
service shop (RayComm) in England has come up with a fix.
USA hobbyists have been sending their R-1's over the pond
to have this problem remedied to the tune of $100 or so
plus shipping & currency conversions.
Not having an R-1 with which to work and test, I can only
make an educated guess as to the nature of the problem
and any remedy, however I have studied the Service Manual
for the R-1 and have reached a conclusion about a remedy.
There is a decided weakness in FL-1 on the DETA board; it
is much too wide for good AM operation in the first place
but it might also be defective to the extent that it
allows spurious & extraneous out of band signals to pass.
Replacement of FL-1 with a quality 455 KHz IF filter will
remedy the "image" problem, not to mention Adjacent Chan¬
nel Interference problems down in the shortwave bands!
I am now looking for an R-1 on which to finalize this and
other possible modifications. I will offer a substantial
discount to the first three people who send me an R-1 for
this remedial service. If not successful, there will be
no charge and the R-1 will be returned in a condition
equal to or better than when received, inquire. 73/bc
"THE WORLD SCANNER REPORT" (c) 1991-2; V2N1 - January, 1992; Page 7
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SCHEMATIC DIAGRAM FOR FATMAN KEYBOARD INTERFACE SUB-UNIT
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"THE WORLD SCANNER REPORT" (c) 1991-2; V2N1 - January, 1992; Page 8
SCHEMATIC DIAGRAM FOR FATMAN COMPUTER INTERFACE SUB-UNIT
CONFIDENTIAL SUBSCRIPTION ORDER: Please print clearly
12/27/91 SUBSCRIPTION RATES & ORDER BLANK Y2N1
USA RATES: (Canada +10$; Other Foreign +20$-$urf or +40S-Air)
HSR BACK ISSUES ONLY USA $$ Check Items
1991 Single copies; your choice: 1 ea $ 4.00
1991 (1st 6-mos, Jan-Hay/Jun) 5 ea $15.00
CITY: STATE: ZIP:
1991 (2nd 6-mos, Jul-Nov/Dec) 5 ea $15.00
1991 (1st Year, Jan-Nov/Dec) 10 ea $25.00
PHONE:f 1 AMT ENCLOSED: $
HSR CURRENT SUBSCRIPTIONS ONLY
1992 Single copies; your choice: 1 ea $ 4.00
THE BELON QUESTIONS ARE OPTIONAL BUT KILL HELP US HELP YOU!
1992 (Jan-May/June) 6-mos 5 ea $15.00
Radio Interests? (Put YEARS OF EXPERIENCE in each block that applies)
YHF-UHF Amateur CB Shortwave Professional
Scanning? Radio? Radio? Listening? Radio?
1992 (Jan-Nov/Dec) 1-yr 10 ea $25.00
1992-3 (Jan 92-Nov/Dec 93) 2-yr 20 ea $45.00
OTHER LITERATURE AVAILABLE
HOBBY RADIO BUYER’S DIRECTORY $14.95 ppd surf
SCANNER MOD HNDBK. Vol-1: $17.95 + $3.00 SSH *
List makes & models of your scanners & other radio equipment:
Describe your technical abilities & interests; use reverse as needed.
SCANNER MOD HNDBK. Yol-2: $17.95 + $3.00 SSH *
* Canada USS4 SSH; Other Foreign USt5 SiH; extra for Mr Hail
MAKE REMITTANCE PAYABLE IN US FUNDS TO: COHHTRONICS ENGINEERING
Enclose a 410 S.A.S.E. and one loose extra stamp if you want
hobby info & personal reply! Business/trade inquiries exempt.
SCHEMATIC DIAGRAM FOR FATMAN CODE CONVERTER SUB-UNIT
TD/OCes U/-D*W /Wfi} o/t /x'V/VS
'THE WORLD SCANNER REPORT" (c) 1991-2; V2N1 - January, 1992; Page 10
"THE WORLD SCANNER REPORT"
PO BOX 262478
SAN DIEGO, CA 92196-2478
IN THIS ISSUE
t 1992; The Year of the Interface
+ Schematic Diagram for Last Month's Serial Data Interceptor
t What's Up for 1992?
+ Review of the RW Systems SC-2 Scanner/Computer Interface
t Review of Datametrics Computer Aided Scanning System
+ The FatMan Do-It-Yourself Scanner Computer Interface Project, Part 1
t Modifications for the PRO-26
+ hew ICOM R-1 Has Bugs; Possible Remedy
FIRST CLASS MAIL