DEC PC04 Paper Tape Reader/Punch
rickb at bensene.com
Mon Mar 28 13:14:55 CST 2005
I've got a DEC PC04 punched tape reader/punch that I've been working
on getting running on my PDP 8/e.
The punch seems to work well.
The reader, on the other hand, has a problem. The 2^2 bit is always stuck
low. So, I started tracing things down, and found that the phototransistor
in the read head at that bit position is 'dead'.
Problem is, the reader uses an array of 10 phototransistors, (8 for data
one for sprocket hole detection, and the last for detecting an "out of tape"
arranged in a linear array with 0.10 spacing, with built in lens bubbles.
There's no way to substitute just the one failed phototransistor.
I can't find anyone online that has anything similar to this array
I'm hoping someone out there has experienced a similar situation, and may
some ideas as to how I can get the reader working 100% again. I want to run
of the MAINDEC diagnostic tapes on the CPU, but it's tough without the
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