Discussion about the Korg PolySix synthesizer

AFter some parts came from Newark, I did the following:

1. Mounted a socket and replaced two 74LS08N chips
2. Installed two LM13700N chips in place of the LM13600 chips

Results:

FIXED: - All Bank LEDs as well as 1, 2, 3, 4 remain ON.
FIXED: - Found stays ON
FIXED: - Sub-osc does not seem to work
FIXED: - Octave button does not seem to work

That's very encouraging!

VAC Mode works!
VCA Attenuator works!
Effects work!
VCO Waveform works!

What is not working:
LFO: LED stays on and cannot change the frequency.

Let me know what you think.

Thanks a lot, and have a great week-end.

Yash


--- In PolySix@yahoogroups.com, Malte Rogacki <gacki@...> wrote:
>
> At 13:43 Uhr +0000 08.10.2012, 7yash wrote:
> 
> > What does not work:
> >
> > - All Bank LEDs as well as 1, 2, 3, 4 remain ON.
> > - Found stays ON
> > - LFO appears to always act upon the pitch
> > - Voice 5 seems dead. A swap of both SSM chips on that segment did not
> >change a thing
> > - Sub-osc does not seem to work
> > - Octave button does not seem to work
> 
> This has probably something to do with data lines D01 to D03 which in turn
> points at IC31 as the most likely culprit.
> 
> Please check if the the following also are affected:
> 
> - VCA Mode
> - VCA Attenuator
> - VCO Waveform
> 
> The dead voice 5 is unrelated; we can debug this at a later point.
>