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Moog opus 3 gone screwy

Moog opus 3 gone screwy

2011-07-31 by adhmzaiusz

Hey everyone, I'm working on a moog opus 3 right now and for some reason once I put in a few new parts I have a bunch of new problems now, even when I swap out the replacement parts I can't fix these certain issues. I've been scoping around, and the weirdest thing is certain ics that I've scoped just by touching things would start working again, but then later they wouldn't work
anymore.

I think the problems are related somehow. Just a list of whats going on:
1. Articulator mode 1 doesn't work properly, no volume but on key release sound
happens. Toggling attack makes the sound fade in after key release. Mode 2 had
no release but attack, now after switching op amp its the other way around. But
now release isn't quite as long as it should be.

2. Brass section gone. Probing with scope did something where it came back, but
after power off couldnt get it again.

3. FModulation always on when switched on, amnt doesnt work. Delay no longer
works, capacitor doesn't seem to fill beside it anymore.

Im thinking that certain ICs are no longer biased somehow, but I barely know anything about that to know. I guess I should check the values of the resistors where certain IC's have both +and- going into the same port right? This problem is so weird. Any help or suggestions would be appreciated, its starting to drive me nuts
-Greg

PS. Sorry if anyone got the original message my brother screwed with it

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