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> From: Mike WilliamsIt's pretty easy to see if the caps are leaky, since you can remove the
>
> Whilst it's in great cosmetic condition for its age, a
> problem with Voice 2 has just developed. As I have little
> test equipment I swapped chips around between synth voice
> circuits to find that the CEM3372 chip in Voice 2 was
> defective. When I put a good chip in the circuit that didn't
> work either so I think I have a defective chip and a problem
> in the surrounding circuit. By checking voltages around the
> pins of the CEM3372 and comparing these with a functioning
> Voice there are significant differences on pins 17 and 12
> i.e. the VCF out / VCA in across one of the 2.2 uF
> electrolytic capacitors. Consequently I suspect a faulty 2.2
> uF cap and plan to replace that tomorrow to see if that does
> the trick.
> The synth is just shy of 30 years old so I'm wondering whatIt's true that 1980s vintage aluminum electrolytics dry out in time. I
> the best advice is regarding replacement of electrolytic
> caps? I suspect they maybe due to give some problems in the
> synth voice circuits as I've noticed some slight tuning
> stability issues along with a slight portamento sometimes ...
> If a cap goes can it damage the CEM3372? I'm guessing it canNo one knows exactly what's inside them, but the block diagram in the data
> because it looks like that may have happened here! The CEM's
> are relatively expensive to replace (£35 each on eBay) so I'm
> wondering if I should re-cap soon ...
> Does anyone know of a good source of CEM3372 chips? I've readI've heard that too, but it isn't something we were aware of at the time
> that some of the more recent revisions deliver different
> sound qualities to the older revisions, to the extent that
> they are not interchangeable. Is there anything in that?