In a message dated 1/11/01 11:49:09 AM Eastern Standard Time, mrp@sonic.net
writes:
<< Nope, you might be missing the -15V that drives the X DAC though....
Or the X DAC might be blown. I don't know the BZ board very well, so
I'm not sure what else is the the analog section of this board, but it
might be in some sort of a problem with an amplifier or voltage follower
in the X section.
Do you have an osciliscope? Can you trace the output of the X DAC to where
it hits the edge connector to see where you lose -X?
>>
Crazy thing is, is that I'm not losing the signal anywhere, at least not that
I can see. Maybe I have my new scope set incorrectly??
I did socket and replace both TL082's. One CRAZY thing I found today was that
I had a glass .1uf cap (C79, goes across collector and emitter of Q4
Darlington 2N6044) was practically shorted and was reading 7 ohms. I then
found that all of these transistors were bad Q4, Q5, and Q6 (probably
caused by C79). I can see the bad cap blowing the darlingtons, but could this
have also affected Q8 (3904) in the Z amp? This is down the same ground line
from Q4. I haven't pulled Q8 yet, but I'll test it tommorrow.
Any other ideas?
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Received on Fri Jan 12 01:12:55 2001
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