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110 VCA/RM Troubleshooting

2001-07-25 by jpotter@it.rjf.com

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).

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