Vintage Synth Repair

At 15:21 Uhr -0400 04.05.2008, Roy J. Tellason wrote:

> I'm amazed that there weren't more failures in the Omni, what with them using
> a 25V cap in a circuit that could potentially see 30V across it.


There certainly are enough failures, especially given the number of
tantalum caps in the Omni (all in all there must be around 80 or more caps;
I didn't count them all). Failure of caps in the gating circuit usually
results in stuck notes.

I'm currently trying to fix an Omni, btw. Progress so far has been good but
there are still some problems.

I've heard about the problem with the "potentially 30V" issue but cannot
really see how this would happen - at least not for the main gating circuit
and the power supply decoupling. But then I'm not really fluent in those
things; so I would be glad if someone could give me an explanation (I'm
always eager to learn about this stuff).

-- 
Malte Rogacki gacki@...
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"Don't forget to TURN ON THE SYNTHESIZER. Often this is the reason why you
 get no sound out of it." (ARP 2600 Owner's Manual)
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