[sdiy] thermal antagonists

[Colin f]

> What parts can be temperature sensitive? I assumed a problem 
> that came and went with heat had to be a trace or connector 
> that was shorting or opening when the metal expanded. Is it 
> possible that the vactrols were at fault or did I fix a 
> solder related problem whilst throwing away $20 in Vactrols?

Not sure about temperature related problems, but I have worked on a couple
of old synths recently which use vactrols for final volume control and poly
portamento.
The failure rate in the vactrols was over 50%
So in my experience, if there's a vactrol in the circuit, it's the first
thing I'd check.

Cheers,
Colin f