29 Apr
2005
29 Apr
'05
11:16 p.m.
I used to service these machines for Western Union years ago.
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On 28-Apr-05 at 21:27 Bill Kotaska wrote:
I am looking for troubleshooting tips for a 33
teletype.
I'm testing in local mode and am getting incorrect characters
on (almost) every keypress. The characters will change even
with repeated pressings of the same key. I am pretty sure the
keyboard is outputting the correct codes.
Never assume. One problem area we had was that the stiff spring-contact wires that the
keyboard uses to set up the code can get dirty or oxidized where they contact the common
busbar. Check this. Also, check the wiring between the keyboard and the distributor
plate.
I wiped down the distributor surface (it was pretty
grimy) and no change.
I tried adjusting the range finder but could never find a point where the
characters were consistent.
Did you change the carbon brushes in the distributor rotor? That was another problem area
for us.
Is it possible to disconnect the motor drive belt and
rotate the shaft
manually to get a closer look at what is happening mechanically?
It's very hard to see what is going on in the selector area with the
shaft spinning so fast.
Absolutely it's possible. That's how we troubleshot a lot of problems.
I would, however, strongly recommend that you try to get a service manual for this beast.
It came in a three-volume set.
Happy tweaking.
-=-=-=-=-=-=-=-=-=-=-=-
Bruce Lane, Owner & Head Hardware Heavy,
Blue Feather Technologies -- http://www.bluefeathertech.com
kyrrin (at) bluefeathertech do/t c=o=m
"If Salvador Dali had owned a computer, would it have been equipped with surreal
ports?"