On 31 Jul 2006, at 18:43, klosmon wrote:
> Unfortunately, there are a number of possible causes: power supply
> going
> out of regulation; reset needing to be recalibrated; dead latch
> ICs on
> the CPU board; etc.
Reset calibration - I don't know where the resistor goes. It mentions
a location in the service manual, but I can't find it. Regardless...
I think that might be part of it, but random tweaking doesn't sort it.
Latch ICs... well, maybe. It's doing one really odd thing; any
programming involving the VCOs seems to break the patch selection/
kick it out of manual, and I can't select the sub oscillator.
Power supply checks out with multimeter as all voltages correct.
> Is this one of the units that had battery-leak damage in the past?
> Even
> when repaired, these units can develop troubles later on, due to
> hidden
> damage to the board traces & continuing decay from traces of acid that
> weren't cleaned up.
I don't see any damage; this one has a blue battery with 3.6v
retained so needs a new one ASAP. Everything looks original. I
already need to replace a 2056 due to a stuck envelope on it, but
that I already know about - TBH the 368B board is just fine as I've
tested it with my other Polysix.
Richard
--
Tasty Other - Because Far Too Much in Life Makes Sense
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