[GreenKeys] Model 33 progress (sort of)

[Brad]

I guess I was kidding myself about having time during holidays, but tonight
I finally did the 20ma wiring change on my 33.  I continue to be frustrated
by an L coming up most of the time as an H.  I've really cleaned the key
contacts as much as I think I can.  And the L is coming out more often than
before, but still not there.  So tomorrow or on the weekend I hope to
finally test this thing with an actual computer and see where my problem is.

 

I'm also dogged by an issue where after about 30 minutes, the typing becomes
jibberish.  I'm sure this must be a cap, but I've tested every cap even when
it's going wrong and unless I'm doing something wrong, they all come back
ok. Ditto for resistors.   I'm thinking this must be one of the big caps
given the time it takes for a problem to materialize.  I can't see anything
else that could overheat slowly like that or start putting out the wrong
voltages.  I have the 1500uf cap Wayne was kind enough to give me which made
a massive improvement in operation (prior to changing that, the machine
buzzed loudly and mostly produced garbage when typing).  But it is second
hand, so it's possible maybe it has issues I'm not diagnosing.  There are
also two, I think, new old stock (or new) 250uf caps I got off ebay.  I've
tried swapping them around but the problem still crops up around the same
time.

 

Anyway, looking forward to testing her out tomorrow, if I can figure out how
to wire it up to my SWTPC.. which is my other question.. where are the wires
for the connection to whatever you're connecting to coming from?  I do have
a two wire (black and red) pair coming from Connector 2.

 

 

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