Discussion about the Korg PolySix synthesizer

Well, what are the other hints? I'm curious...

as for the 4066, I had a few going bad on my Kawai SX210, interesting 
input.

I would not sell the MK2, I like mine so much. But if you still want 
to sell it I know someone in the UK who will be more than happy to 
buy it from you.





--- In PolySix@yahoogroups.com, Niels Ott <niels.ott@...> wrote:
>
> Hi gil and others,
> 
> no unfortunately not. I'm quite busy so I didn't find time for 
further
> experiments. I got some great hints from German synthesizer gurus, 
though.
> 
> One of those hints said: The 4066 chips go bad whenever the voltage 
on
> their input comes close to their supply voltage. So if you're 
messing
> with those, put them on a socked and be sure to have replacements
> available...
> 
> And some other hints, now I hope to find the time soon.
> 
> Still I'm wonderhing whether I will sell the Trident MK2 or not 
once I
> got it fixed. I'm not a collector, I'm trying to be a musician.
> 
> Best,
> 
>    Niels
> 
> 
> gil_we schrieb:
> > Hey, any news ?
> > 
> > 
> > 
> > 
> > --- In PolySix@yahoogroups.com, Niels Ott <niels.ott@> wrote:
> >> Hi gil,
> >>
> >> the SSM* are OK, I checked them. I had a nice day with the 
> > oscilloscope
> >> and found out: The output of the signal generator board is 
already 
> > bad.
> >> Then I replaced two opamps 4558 which I suspected to be the 
problem 
> > but
> >> it didn't help. Still 0V out instead if the signal on oszillator 
2 
> > (VCO
> >> 1 (sic)).
> >>
> >> Next suspect was the CMOS switch which I replaced by a similar 
> > type. But
> >> Somehow it wasn't similar enough, so I got -9V in the output 
now, 
> > which
> >> is definitely not good.
> >>
> >> I'll keep on soldering. ;-)
> >>
> >> Best,
> >>
> >>    Niels
> >>
> >>
> >> gil_we schrieb:
> >>> Did you switch SSM2056 and SSM2044 between voices to see if it 
> > may 
> >>> lay there ?
> >>>
> >>>
> >>> --- In PolySix@yahoogroups.com, Niels Ott <niels.ott@> wrote:
> >>>> Hello there,
> >>>>
> >>>> my Trident MK2 is defective.
> >>>>
> >>>> Symptom: VCO 1 is defective for one voice.
> >>>>
> >>>> Up to now I was able to found out: Input 1 of IC704 (4x CMOS 
> >>> switch) on
> >>>> KLM-379 doesn't get the VCO signal on voice 7. On all others 
it 
> >>> does.
> >>>> There are some oddities with op amp IC707 but I'm not yet 
sure. 
> > The
> >>>> schematics and the circuit board design hint to the direction 
> > that 
> >>> IC707
> >>>> "feeds" IC704.
> >>>>
> >>>> The IC707 is a 4558, I assume that it is similar in the 
Polysix.
> >>>>
> >>>> Did anybody of you experience a similar problem? What about 
> >>> replacing
> >>>> the 4558, did this help?
> >>>>
> >>>> Furthermore, some of the 4558s carry a date stamp of 1997 
which 
> >>> means
> >>>> they must have been replaced by an earlier owner.
> >>>>
> >>>> Unfortunately there is no shop selling electronic parts in 
reach 
> > so 
> >>> I
> >>>> can't just go for it and try replacing it. Mail order is an 
> > option 
> >>> but
> >>>> not for a few ICs...
> >>>>
> >>>> Thank you for commenting.
> >>>>
> >>>> Best,
> >>>>
> >>>>   Niels
> >>>>
> >>>
> >>>
> >>>
> >>>
> >>> PolySix "Digiest" Page: http://www.acc.umu.se/~amber/Poly6 
> >>> Yahoo! Groups Links
> >>>
> >>>
> >>>
> >>>
> > 
> > 
> > 
> > 
> > 
> > PolySix "Digiest" Page: http://www.acc.umu.se/~amber/Poly6 
> > Yahoo! Groups Links
> > 
> > 
> > 
> >
>