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Modification for 26 

JANUARY, 1958 
25 Cents 
Vol. 6 — No. 1 






Radioteletype Convention at University 

of Arkansas 

We here at UNH think we did a pretty 
good job of working the contest consider- 
ing a few essential facts. First, we didn't 
have any tape equipment nor were we us- 
ing the best of equipment. In fact we 
were using a model 12 and W2PAT type 
TU with toroids (hand wound). The con- 
verter has no means for compensating for 
odd shifts and makes tuning rather difficult. 
The model 12 is seven tube keyed (6L6s) 
and this by no means kills all the noise 
in the revr. The transmitter, as does the 
whole rig, belongs to K1DHJ and is a 
combination of a Viking adventurer and 
another final a la handbook and QST. 
pp807s in parallel and we generally run 
it at about 100 watts input to a balun fed 
windom antenna sixty feet high running 
north-south. All in all the antenna is the 
only piece of gear which belongs to the 
club and even it has a pretty SWR. At 
present we are trying to get some money 
for a receiver from the E.E. Dep.t here at 
school and so far no success. One of the 

local companies has offered to give us some 
equipment but we have no idea just what 
that will be yet. Or when. Next year we 
hope to have a model 26 and some tape 
equipment . . . look out for us then ! ! If 
the Society still uses the pictures of shacks 
for their cover please use the "before” 
shot if it comes out ok. I’m sorry we 
don’t have any better negatives to send 
you. No professional photographers in the 
club though. Have to 'shut off the motor 
now and start studying Physics for the 
test Tuesday. See you oi» 20 sometime 
when there is no gang around ok? Say, 
one more question: what about these guys 
like W2RUI etc. that no one hears until 
SS time and then they bull their way 
around with tapes and kws? ? ? ? Not very 
nice procedure to zero the W5s when you 
finish talking with them either, hi. 



Please bring to the attention of all who 
are interested that W5YM will sponsor a 
radioteletype convention on Sunday, 16 
March 1958 for the purpose of stimulating 
Arkansas RTTY activity and presenting 
discussions of RTTY principles and dem- 
onstrations of RTTY equipment. This meet- 
ing will be held in the auditorium of the 
Engineering Building on the University of 
Arkansas campus. 

This meeting is being held on the day 
following the Engineers’ Day Open House 
Activities; displays set up by the Electrical 
Engineering Department will be shown to 
those attending the convention. 

Although registration is not required for 
this convention, we will appreciate a post- 
card from those who wish to attend so that 
we can plan the activities in accord with 
the number who will be present. The 
main convention will begin around 2 P. M. 
A dinner meeting and/or a program for 
the XYL and Junior Operators will be 
planned if sufficient desire for these ac- 
tivities is indicated on the cards. If inter- 
est warrants, we shall plan to establish an 
Arkansas RTTY Society and elect officers 
at this convention. 

Any persons who can present talks or 
demonstrate RTTY and related equipment 
are urged to contact us so that activities 
can be properly scheduled. W5YM will 
present an operating display of RTTY sta- 
tion equipment and will demonstrate the 
equipment which has been given to the 
University of Arkansas by the Teletype 

Corporation of Chicago-Little Rock and 
consisting of a Model 28, a Model 14 typ- 
ing reperforator with keyboard, and a tape 
perforator and transmitter-distributor table. 

Those who desire to stay overnight can 
make reservations with Hotel Mountain 
Inn or one of the several motels located 
in this RX area. Fayetteville is served by 
Central and Skyways Airlines offering con- 
nections to Little Rock and with all ma- 
jor airlines. We can provide transportation 
from the airfield for any who wish to fly 

All those who send in postcards will be 
placed on a mailing list for the distribution 
of any RTTY literature which may be 
available through this station. 

A bulletin station the final arrangements 
for this convention, the activities planned, 
and the speakers and their subjects will be 
distributed prior to the meeting date. As 
stated above, many of the activities will 
depend on the results of the postcard sur- 
vey, so please get ’em in early. 

Amateur Radio Club W5YM 

of the University of Arkansas 
Room 309 Engineering Building 
Fayetteville, Arkansas 


Chairman, Activities and Eqpt. 


FRED, K51IX, President 

WALT, W5VKE, Trustee 





The Model 26 Ranger Finder Modification 


( Cover 

Count over from right of the hinge to 
a point between the ninth and tenth seg- 
ment . . . scribe a line downward two and 
three-quarter inches . . . then scrihe a line 
to the right for two and three-quarters 
inches (lower edge of door then back up 
to the hinge . . . (should be midway on 
the fifth segment from right . . . 

Remove plex-glass and insert jeweler’s 

Photograph ) 

saw at point between the ninth and tenth 
segment . . . following scribe downward 
and to the right and then upward, a door 
should be free to pivot on the existing 
hinge and also clamp shut with no further 
modifications 1 1 ! ! ( Except to add a tab 
to open it ) . . . Suggest you paint the cut 
edges and line the stationary edges with 
tape . . . 

Transistorized "RTTY" Channel Amplifier 


For those “tinkers” who are interested 
in new and various types of terminal untis 
(TU’s), the following circuit should prove 
of interest. Five transistors and five diodes 
go into its makeup. 

The input is coupled thru a line trans- 
former (500 ohm to 20,000 ohm) to a 
limiter made up of the following elements, 
a 15,000 ohm series resistor and a pair of 
back-to-back diodes with two 1.5 volt bat- 
teries for bias to set limiting levels. The 
output of this limiter drives a base driven 
2N109 which in turn drives a pair of 
2N109’s to provide the split phase opera- 
tion of the selective network. The frequen- 
cy determining portion consists of two 88 
mhy toroids, tuned with a 0.066 mfd and 
a 0.033 mfd capacitor. The 88 mhy and 
.066 tune to the MARK signal. Connected 
to these two tuned circuits (in series) are 
two 1N69 diodes which have load circuits 
of 470,000 ohms and .01 mfd capicators 
in parallel. Across the two DETECTORS 
is connected a 100,000 olnn potentiometer 
which allows some adjustment for differ- 
ences in output of the selective circuits. 

Some additional filtering takes place with 
the .05 to ground and thru the 56,000 ohm 
resistor to the base of the 2N146 (equiva- 
lent DC amplifier, which drives the 2N- 
301A output amplified, which in turn op- 
erates the PRINTER MAGNET. An addi- 
tional output is provided to key either a 
TONE GENERATOR for AFSK or key an 
FSK DIODE. For the model 26, use ap- 
proximately 7.50 at 50 ma. This is well 
above the current requirements for a 26, 
but remember this is at 7.50 volts. Print- 
ing range has been found to be about 70 
points. Some of the specifications are: will 
print at -47 DB below 0 level, starts to 
limit at -45 DB. Has 300 cps band pass, 
total current (less magnet current) is ap- 
proximately 4ma. No signs of “ringing” as 
soon as limiter takes hold (-45DB). NOTE 
—88 mhy and .066 and .033 are only ap- 
proximate values. Tune for exact frequen- 
cies. Adjust the 100,000 pot for equal 
swings on MARK and SPACE. Also ad- 
just the -14.0 volt tap for proper magnet 





Just thought I’d pass along a method of er VFOs, however it is no great loss if it 
FSKing the Viking Ranger (and possibly doesn’t. 

the VFO’s in all Johnson rigs which are of I can get up to about 900 cps shift (if 
the same design as the Ranger’s) which 1 I wanted it) on 80 meters and over that 
stumbled upon during some “TINKER- on bands (20 meters and above). Can get 
ING.” only around 500 cps on 40 meters. 

It is so very simple— costs less than one At least it would be a wonderful meth- 
buck— NO conversion of the Ranger at all. od for new short shift of only 170 cps. 
Takes only a few minutes to hook up— Each VFO will probably require differ- 
gives beautiful right-side-up FSK. ent component values; here is the method 

There is only one disadvantage, it won’t I found by my “tinkering.” 
work on 40 meters (at least on my VFO), Possibly this method might work on oth- 
which follows the old saying: “You can’t er makes of VFOs. Now back to my 
get something for nothing.” “tinkering” so I can find a way to FSK my 

My method may not work on all Rang- RANGER VFO on 40 meters . . . 

FS < ADJ. 





Having built up and tried several of the 
usual “modulated oscillator” types of AFSK 
generators and being plagued by drift and 
unstability due to trying to switch a con- 
denser with a variable resistor network it 
was decided to try and dope up a signal 
source using a MOPA hookup to get the 
signal source out of the keyed circuit. 

The attached diagram shows the final 
result. It is a pair of electron coupled os- 
cillators generating the space and mark sig- 
nals continuously followed by a pair of dif- 
ferentially keyed Class A amplifiers. 

The oscillators use two "load pot” 88 nth 
toroids with the coils in series and the cen- 
ter tap used for the cathode connection. 
To avoid overdriving the keyed stages it 
is necessary to reduce the plate voltage 
on the oscillator with the 270K series re- 
sistor giving about twenty volts plate volt- 

ON “space” the bias divider network 

supplies 50 volts of negative bias to the 
grids of the keyer tube and to the grid 
of the “mark” amplified cutting off the 
mark signal while the space signal goes 
through the space amplifier tube. On the 
arrival of a 50 volt positive mark signal 
from the keyboard the bias voltage goes 
slightly positive permitting the mark am- 
plifier to conduct. At the same time the 
keyer tube conducts and raises the cath- 
ode voltage of the space amplifier suffi- 
cient to cut off this tube and shut off the 
space signal. The 25K variable resistor is 
adjusted to the necessary cutoff voltage. 

A 47K grid resistor is used in the grid 
of the space amplifier to reduce the driv- 
ing audio voltage to give equal output on 
both frequencies. 

This unit gives steady AFSK, good wave- 
form and keying and has cured the “jit- 
tery” AFSK signal here. 

Subscription Rate $2.50 Per Year 

RTTY is the Official Publication 
of the 

RTTY Society 
of Southern California 

and is published for the benefit of all 
RTTY Amateurs and Experimenters 

Permission to copy is granted 
provided credit is given. 


For Information Regarding the 
Society Contact the Following; 

W6CLW — Ed Simmons 
W6AEE — Merrill Swan 
W6SCQ — Lewis Rogerson 

For Traffic Net Information: 

For “RTTY” Information; 






It occurred to me the other day that 
some of the boys might be interested in 
the reprints of the enclosed sheet. 1 shall 
be happy to send copies to anyone inter- 
ested at 30c each postpaid. Note that the 
weather code is on there too . . . W1BIY 
(The chat is an excellent on which gives 
the characters in lower case and the va- 
rious upper case, such as weather and 
commercial as well as communications, 
with the code signals which operate to 
produce them. Space did not allow repro- 
duction.— Ed. ) 

- 0 - 


The fourth annual amateur RTTY din- 
ner will be held in New York City on 
Monday, 24 March 1958. Reservations are 
available from Calyton Cool, W2EBZ, 443 
West 47th Street, New York, 36, N. Y. 
Clay requests the following, if you plan 
to attend. Present and historical background 
and description of your RTTY station and 
activities. If available, a photograph of 
your station. Your commercial affiliations. 
Reservations are seven dollars, send check 
made out to Clay Cool to assure reserva- 
tion . . . 

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-General Dynamics Corpora- 
tion and the Haloid Company unveiled 
what they described as the fastest com- 
mercially available device for high-speed 
printing of computer data. 

Developed jointly by Haloid and the 
Stromberg Carlson division of General 
Dynamics, the machine will print the out- 
put of electronic computers at the rate of 
4,680 lines ( about 65 feet ) per minute. 
According to the manufacturers, that’s 
five to 10 times faster than the speed of 
present electromechanical printers. 

The machine is known as the S-C 5,000. 
It translates electric impulses from the 
computer into numbers, letters, and sym- 
bols by means of a “beam tube” which 
operates in much the same way as a tele- 
vision picture tube. 

Suggested uses include preparing bank 
statements, billings, insurance premium no- 
tices, production control reports, address 
labels, and missile and aircraft engine data. 

- 0 - 

London Telegraph - 11-2-57 
Copenhagen, Saturday— Peter Lie, a Dan- 
ish hypnotist, claims he hypnotised a man 
by teleprinter. Lie said he ordered a tele- 
printer operator to fall asleep for three 
minutes and to be insensible to pain 

He dictated the message on a teleprint- 
er in another room. A doctor signed a state- 
ment saying the operator slept for three 
minutes and had shown no reaction to 
needle jabs in the arm.— Reuter. 

in conclusion, though hams and farmers 
are cronic complainers about the weather, 
actually conditions were excellent. WWV 
went all out and sent “N7” before, dur- 
ing and after the contest period. There 
was little or no skip on twenty for W9TCJ, 
W9SPT and W9GRW at 300-400 miles 
were loud many hours after sunset and 
they were working each other then* This 
unusually good situation for communica- 
tion played havoc by bringing in interfer- 
ence from all directions to us here in the 
middle of things. 

But I am sure it was the best contest I 
was ever in and there were so many new 
stations that one could not possibly work 
them all, which made it jolly sport and a 
practical road test of equipment and op- 
eration under severe interference condi- 
tions. Narrow shift should be tried next 


69 x 2 x 30 is 4,140. (Nov. SS) 73, 


Our New Zealand friend Bruce ZL-WB 
visited this qth today. Bruce said he was ' 
impressed with much that he has seen in 

our country, but Bruce was not half as 
impressed as were his hosts this afternoon 
namely Bill, Merrill and *Ted'. When re- 
freshments were offered Bruce held back 
while the American hams let their thirst 
run away with their manners and asked for 
a beer please. Bruce theh spoke up and 
asked for lemonade. His hosts figured that 
New Zealand hams must be different and 
boy, they were so right. Bruce got his lem- 
onade and promptly mixed it with beer, 
half and half! Like I said, boy, did Bruce 
impress us! That’s all. 

Sig. Ted. 

Oh yea . . . one other thing . . . it’s 
good! Darned good! Honest it is! Merrill 
is rewriting the bylaws of the SCRTS to 
specify beer and lemonade mixed at all fu- 
ture SCRTS gatherings. (P.S. Just as he 
left Bruce spoiled everything by telling the 
gang that in his country, mixed beer and 
lemonade was a lady’s drink. How do you 
like that? ) 

- 0 - 

I enclose a copy of a letter which is an 
interesting resume of my RTTY experiences 
in the first ten days of operation. Possibly 
you can use this from the standpoint of 
one RTTY’ers experience in breaking into 
RTTY. - 73 - -W2ATQ 

- 0 - 

Dear Bill: 

Many thanks for your letter which crossed 
mine in the mail. As yet I haven’t received 
a reply and I am hopeful that I dispatched 
it to the proper address. Since I had your 
address in the office and I wrote to you 
prior to my departure to Washington, it 
was necessary for me to go through the 
call book beginning with W8A until I hit 
W8TLW which I now admit was not the 
most pleasant undertaking. Despite all my 
questions I decided to get started without 
your reply and after looking at various 
periodicals I determined that 7140 ke was 
the TTY frequency. As a consequence I 
had a crystal ground for this frequency on- 
ly to discover that most of the stations 
hereabouts are operating up toward 7145 
kc. In any event I am on 7140 and have 
worked a few stations who replied that 
my keying was reversed. This struck me 
as being rather peculiar since I am using 
one of our commercial frequency shift 
units. I changed it to turn it over by the 
use of a polar relay which does nothing 

but increase the possibility of bias, and 
then called a few fellows and to my 
amazement received no response. After a 
few more days of monitoring I suddenly 
discovered that it is necessary to turn on 
the beat oscillator and use the old fash- 
ioned CW method to establish contact and 
then hope that the recipient has equipment 
which will receive any shift up to 850 
cycles. Here again I found that this is not 
the case and that you are in trouble in 
most instances if you don’t shift the exact 
amount. I suppose this is a matter of being 
entirely new at the ham RTTY game and 
it seems funny to look back at the time 
when you and I developed this sort of 
thing at the laboratories in 1941 and sud- 
denly find that you are a greenhorn, so 
to speak. Now I can go back a few steps 
and conform to the way it is being done 
but I wonder whether this is the correct 
approach. 1 am using a Collins 51J-4 re- 
ceiver which feeds a Westrex 50 Type con- 
verter which will take any shift from 75 
to 900 cycles normally or reversed. The 
transmitter is a standard Westrex 350 watt 
output which is normally used in airline 
and point-to-point services. The filter in 
the converter is 1000 cycles wide at the 
6 db point and about 2000 cycles at 50 
db and with this I find an additional dif- 
ficulty; that being that some of the RTTY 
stations drift as much as 3000 cycles dur- 
ing a transmission. This is difficult, par- 
ticularly when in commercial services we 
try to hold this drift to 25 cycles during 
the daily cycle. Of course, as a typist I 
am not very proficient but that doesn’t 
worry me a* much as the time taken by 
the technical problems which 1 men- 
tioned above. I will appreciate some word 
from you Bill as to your experiences for 
I have now concluded that 1 now require 
a group of crystals which will operate any- 
where from 7140 to 7149 to effect contact. 

Whenever you are ready I should like 
to arrange a schedule with you and we 
can carry' this on further via RTTY. (Am 
using a Model 15.) 

- 0 -