Discussion about the Korg PolySix synthesizer

--- In PolySix@yahoogroups.com, "Chromatest J. Pantsmaker" 
<chromatest@...> wrote:
>
> It's probably the traces... unless the corrosion has leached into 
that
> chip.  Personally, I've not seen anything "break" inside a P6 other
> than the corrosion and normal wear and tear.
> 
> Sorry I can't help answer your actual question though.
> 
> On 11/9/07, spistrich <wasteking@...> wrote:
> > does anyone know what IC 31... on board klm-367  does?  it would 
be the
> > first chip to be damaged from the acid leak....it is a 74LS08 type
> > chip. readily available from Digikey, but I really would like to 
know
> > what functions it controls. this info might help explain my 
polysix's
> > odd behavior after battery leakage rather than just blaming the 
traces.
> >
> >
> >
> > PolySix "Digiest" Page: http://www.acc.umu.se/~amber/Poly6
> > Yahoo! Groups Links
> >
> >
> >
> >
> 
> 
> -- 
> .sig
> -Chromatest J. Pantsmaker
> http://www.chromatest.net
>
`well, the reason im wondering about IC 31 is that in the repair 
exaple shown on the Old Crow synth repair site...he said he had to 
replace the IC 31 in addition to trace repair, but didnt describe 
what the problem with the chip was.....i can understand how corroded 
traces could loose continuity...a couple did on my polysix, but the 
odd behavior i see is almost like 'too much' continuity-- things that 
dont turn off.  this could be explained by conductive acid getting 
into the IC... Because i cant see a problem with the traces now, and 
continuities are fine. The replacement 74LS08 chip is cheap ...and i 
would have to pull the old one to check/repair the traces under it. I 
just wonder what the IC 31 does? does it control track selection 
and/or memory  to tape download ? 

(p.s. i have had to replace voice chips on a dead voice...but the 
LED's in each voice channel made diagnosing  that easy.)