Hi all there,
I've picked up another Polysix in good external conditions, but dead on the electronic side.
It had the common battery leakage on a small area not so bad than others that I've already repaired, so I've restored it at usual,
Now some minor issues are still there.
Octave scaling is irregular, so, suspecting a faulty HTV1501 photocopupler as written in other topics, I've swapped the voice board with a spare working one, and the issue disappeared, then the issue might be on PC1.
I can't understand which spare is better for this IC, someone says VTL5C1, some other says VTL5C3,
MG level doesn't works properly.
This issue is driving me crazy.
Frequency and Delay Pots are working flawless, but once engaged, it's impossible to dim or turn off the LFO modulation effect by turning the "level" pot.
The pot itself is working, either the IC2 4051 on control board is working, i've followed the Data and A B C cables for signals routing and they are without any interruption.
I've checked the IC6 also, perfect.
Connection cables are ok.
Tips about where to dig?
More than this, it doesn't save patches.
I've checked the memory chip's electrical signals, and it seems working properly, giving the same responses than the working one.
.
I have also made the Lithium battery mod as shown in service manual appendix, but there's no way to save patches,although the buttons are working properly.
Any help is very much appreciated, thanks.
Sorry for my bad english,
Bye,