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Subject: 110 VCA/RM Troubleshooting

From: jpotter@...
Date: 2001-07-25

Finished putting together a 110 late last evening (maybe that's the
problem).

The RingMod part works fine. I can use the X & Y in and get audio at
out at about the same level as it goes in.

My problem seems to be with the VCA section. I plug audio in but
only get faint audio out (with the Gain all the way up). It is
working but seems to greatly attenuate the source - if I turn the
mixer way up and sweep the gain on the VCA counterclockwise I can
hear it's effect.

Don't know if this is good/bad/otherwise but if I touch the very tip
of a cord to either out on the 110 I pick up a radio station - I
don't know if that means something isn't grounded correctly (???)

I've checked all the polarity sensitive components and all are in the
right orientation.

I've checked the resistors and most of the caps several times and
everything is OK there. Haven't triple checked the axial caps
(printing is really small so I thought I'd get a magnifying glass to
verify) but I'm pretty sure they're correct.

I'm going to double check for obvious shorts but checked several
times during construction and feel fairly confident about that.

Any ideas?

Thanks,

John

PS - the CEM chip doesn't sit absolutely flat on the socket should
it? I had to pinch the legs in to get it to fit in the socket and
it's slightly raised (but inserted all the way in to where the legs
flair out).