Re: Q*bert sound board repair

More information:

I verified that the board (which I am working of for someone else)
originally had a hacked on daughter card. That explains the missing parts
in the amp section.

I replaced them and the amp now works (I can run a damp finger over inputs
and get noise).

Still nothing but a series of clicks from the board startup. They continue
for a while then stop.

Test button does nada.

I have figured out though that the clicks that I am getting are actually the
startup speech (this is a reactor rom set so it should say "Warning core
unstable"). As a note for anyone taking repair notes you can test the speech
clocking by using a 2.2K resistor from the +12 to pin 15 in on the SC01.
That resulted in my being able to hear the speech go by chipmunk style.
Obviously I have some nature of clocking failure.

The chip is setup as a current clocked component. Making it DAMN hard to
trouble shoot the section though.

Time for David's dumb shit tech question of the day: Can I use the amp
section on my meter to help testing this part? If so how should I hook it
up?

This goes for the LM741 (U21) through the 2n2222 (Q1) and the 2n2907A (Q2).

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