[NJARC] printers

[John Dilks K2TQN]

Hey guys,

TTY machines are big and complicated looking, but not that hard to 
work on.  Back in the 60's I worked on a bunch of them and found that 
most are ready to go after a good mineral oil bath (clean it) then a 
good lubrication of machine oil.  True, the ones I worked on had only 
been sitting for a few years, and these have probably been sitting 
for 40 years or so, which means: get the oil around. In and out of 
everything except the motor.  Make sure all the felts are oiled 
thoroughly, (saturated).  Look for oil holes at the bearing points, 
where shafts pass through a casting.

Now, if you want to start a new "look" in clothing, wear a nice white 
shirt and stand directly in front of the model 15 when you turn it on 
after lubricating it, with the cover off of course.  The power switch 
is conveniently located in the front.  :-0   :-)  You won't be a true 
TTY repairman unless you do this at least once.  It's like a right of 
passage.  Wear your shirt proudly!

So before you go to all the trouble to dig out all the test equipment 
-- clean, lube and then hook up a 60-ma loop (current limited to 60 
ma., no more, in the proper polarity and the machine should turn on 
and the hold magnets should have the machine running smooth with only 
the motor turning.  Open the 60 ma. loop and it will "run open" 
(chunk-a-chunk-a-chunk, etc.)  Manually open and close the loop 
quickly and the machine should start to print garbage.  The machines 
were probably pulled from service and are most likely adjusted close 
enough to run.

Typing on a close loop should also provide results.  The keyboard 
should be placed in series with the loop and printer. The characters 
ry typed over and over quickly is a good test.  It exercises the 
machine and all the selectors.

Some machines were 60-wpm (hams used this) and Western Union machines 
and a few others were 66-wpm.  The two speeds are not 
compatible.  And there were some running at 75-wpm.  The gears are 
interchangeable (in pairs, 1 metal for the motor and 1 fiber for the 
machine).  Most tty's had synchronous motors, and some were 
non-synchronous.  The non's had a white pattern painted on the motor 
cooling fins.  These require a shuttered tuning fork to set the speed 
properly.  The synchronous motors are better to have.

Model 15, 19, 26 and 32's are Baudot (5 level code) and 33 and 35's 
are ASCII (8 level code).  15, 19, 26 are 60 ma. loop and 33, 35 are 
20 ma loop.  the 32 I forget.

Hooking two machines in series within the same loop will provide a 
good exhibit for youngsters who can type back and forth.

73, John Dilks, K2TQN

At 12:17 AM 2/20/2007, you wrote:
>Visit our web site - See http://www.njarc.org
>_______________________________________________
>      I talked to a collecter down named Rich Klarr who used to
>   repair printers in years past.He gave me permission give his
>   phone number but no gurentees(SP) he might have the info you need.
>     972-492-6644
>      Jon B.F.
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