Discussion about the Korg PolySix synthesizer

--- In PolySix@yahoogroups.com, "u3dreal" <u3dreal@y...> wrote:
>
> Hello all;
>
> I bought a polysix in rather bad condition...
>
> I did the batteryreplacements and checked to circuits...they seem to
> be OK for both sides of teh PCB
> ...many things were still wrong then I replaced the IC31...and the
octave
> knob and the sub osc were working again.
>
> The Controls are better now but still don't work correctly..
>
> the MG....Delay doesn't work at all and Level gets controlled by the
> VCO PW/PWM knob...? the EG doesn't seem to work either..
> only the sustain can be controlled via the LFO resonance knob..
>
> all the other things like the preset section / loading saving
progamms
> or even sending and receiving banks form external casset recorder
> works....!!!!!
>
> when i try to do the testing procedure with the 56k resistor...the
> following happens.....when i turn the trim clockwise there is a
point
> where is jumps from bankA prog1 to all eight proglights.....this
doesn't
> happen
> for me the two first ( prog 1+2) don' light...sometimes
> its only the first one which doesn't light...
> when i remove the resistor it switches back to prog1 bankA
>
> I have no idea what could be wrong...could it be IC30 or even the
> processor ?? Did you have something simlar ?
>
> How much would a new proc cost?
>
> I really would aprichiate it a lot if you could give me some
advice...
>
>
> thanks in advance
>
> Gregor
>

>

> I have no idea what could be wrong...could it be IC30 or even the
> processor ?? Did you have something simlar ?
>

>
> > Hello all;
> >
> > I bought a polysix in rather bad condition...
> >
> > I did the batteryreplacements and checked to circuits...they seem to
> > be OK for both sides of teh PCB
>
> Make sure it didn't experienced any battery leakage. You can look for
> green rust on the PBCs and the components on both the computer board
> and the one that is place above it, attached to the panel. If it did,
> you'll have to rewire some traced and replace some parts that may got
> defected by the acid...
>
>
> > ...many things were still wrong then I replaced the IC31...and the
> octave
> > knob and the sub osc were working again.
> >
> > The Controls are better now but still don't work correctly..
> >
> > the MG....Delay doesn't work at all and Level gets controlled by the
> > VCO PW/PWM knob...? the EG doesn't seem to work either..
> > only the sustain can be controlled via the LFO resonance knob..
>
> I had similar problem on my Trident, which I solved by replacing a
> few logic ICs on the panels, which were directly related with the
> knobs that didn't work properly. In on case I found that a technician
> who tried to fix the machine, has placed on IC one of the ICs in
> reverse !!
>
>
> >
> > all the other things like the preset section / loading saving
> progamms
> > or even sending and receiving banks form external casset recorder
> > works....!!!!!
> >
>
> So the computer board seems to be ok.
>
> > when i try to do the testing procedure with the 56k resistor...the
> > following happens.....when i turn the trim clockwise there is a
> point
> > where is jumps from bankA prog1 to all eight proglights.....this
> doesn't
> > happen
> > for me the two first ( prog 1+2) don' light...sometimes
> > its only the first one which doesn't light...
> > when i remove the resistor it switches back to prog1 bankA
> >
>
> Normal ?....
>
> > I have no idea what could be wrong...could it be IC30 or even the
> > processor ?? Did you have something simlar ?
> >
>
> I would check/replace the suspective ICs on the panel board first.
>

--- In PolySix@yahoogroups.com, "Gregor Quade" <u3dreal@y...> wrote:
>
> Thanks alot Gil,
>
> I already checked all the traces on the board which might got
> affected by the batteryleak. So far they are all working fine.
>
> The Tip with the logic IC on the frontpanel is very good.
> I'll try that. I also thought of that. but i wasn't sure.
>
> Update to come soon.
>
> Still if anybody has advice i would appreciate.
>
> thanks to all.
>
> Gregor
> >
> > > Hello all;
> > >
> > > I bought a polysix in rather bad condition...
> > >
> > > I did the batteryreplacements and checked to circuits...they
seem to
> > > be OK for both sides of teh PCB
> >
> > Make sure it didn't experienced any battery leakage. You can look
for
> > green rust on the PBCs and the components on both the computer
board
> > and the one that is place above it, attached to the panel. If it
did,
> > you'll have to rewire some traced and replace some parts that may
got
> > defected by the acid...
> >
> >
> > > ...many things were still wrong then I replaced the IC31...and
the
> > octave
> > > knob and the sub osc were working again.
> > >
> > > The Controls are better now but still don't work correctly..
> > >
> > > the MG....Delay doesn't work at all and Level gets controlled
by the
> > > VCO PW/PWM knob...? the EG doesn't seem to work either..
> > > only the sustain can be controlled via the LFO resonance knob..
> >
> > I had similar problem on my Trident, which I solved by replacing
a
> > few logic ICs on the panels, which were directly related with the
> > knobs that didn't work properly. In on case I found that a
technician
> > who tried to fix the machine, has placed on IC one of the ICs in
> > reverse !!
> >
> >
> > >
> > > all the other things like the preset section / loading saving
> > progamms
> > > or even sending and receiving banks form external casset
recorder
> > > works....!!!!!
> > >
> >
> > So the computer board seems to be ok.
> >
> > > when i try to do the testing procedure with the 56k
resistor...the
> > > following happens.....when i turn the trim clockwise there is a
> > point
> > > where is jumps from bankA prog1 to all eight
proglights.....this
> > doesn't
> > > happen
> > > for me the two first ( prog 1+2) don' light...sometimes
> > > its only the first one which doesn't light...
> > > when i remove the resistor it switches back to prog1 bankA
> > >
> >
> > Normal ?....
> >
> > > I have no idea what could be wrong...could it be IC30 or even
the
> > > processor ?? Did you have something simlar ?
> > >
> >
> > I would check/replace the suspective ICs on the panel board first.
> >
>

>
> The 4xxx IC family tends to go bad when old
>
>
> --- In PolySix@yahoogroups.com, "Gregor Quade" <u3dreal@y...> wrote:
> >
> > Thanks alot Gil,
> >
> > I already checked all the traces on the board which might got
> > affected by the batteryleak. So far they are all working fine.
> >
> > The Tip with the logic IC on the frontpanel is very good.
> > I'll try that. I also thought of that. but i wasn't sure.
> >
> > Update to come soon.
> >
> > Still if anybody has advice i would appreciate.
> >
> > thanks to all.
> >
> > Gregor
> > >
> > > > Hello all;
> > > >
> > > > I bought a polysix in rather bad condition...
> > > >
> > > > I did the batteryreplacements and checked to circuits...they
> seem to
> > > > be OK for both sides of teh PCB
> > >
> > > Make sure it didn't experienced any battery leakage. You can look
> for
> > > green rust on the PBCs and the components on both the computer
> board
> > > and the one that is place above it, attached to the panel. If it
> did,
> > > you'll have to rewire some traced and replace some parts that may
> got
> > > defected by the acid...
> > >
> > >
> > > > ...many things were still wrong then I replaced the IC31...and
> the
> > > octave
> > > > knob and the sub osc were working again.
> > > >
> > > > The Controls are better now but still don't work correctly..
> > > >
> > > > the MG....Delay doesn't work at all and Level gets controlled
> by the
> > > > VCO PW/PWM knob...? the EG doesn't seem to work either..
> > > > only the sustain can be controlled via the LFO resonance knob..
> > >
> > > I had similar problem on my Trident, which I solved by replacing
> a
> > > few logic ICs on the panels, which were directly related with the
> > > knobs that didn't work properly. In on case I found that a
> technician
> > > who tried to fix the machine, has placed on IC one of the ICs in
> > > reverse !!
> > >
> > >
> > > >
> > > > all the other things like the preset section / loading saving
> > > progamms
> > > > or even sending and receiving banks form external casset
> recorder
> > > > works....!!!!!
> > > >
> > >
> > > So the computer board seems to be ok.
> > >
> > > > when i try to do the testing procedure with the 56k
> resistor...the
> > > > following happens.....when i turn the trim clockwise there is a
> > > point
> > > > where is jumps from bankA prog1 to all eight
> proglights.....this
> > > doesn't
> > > > happen
> > > > for me the two first ( prog 1+2) don' light...sometimes
> > > > its only the first one which doesn't light...
> > > > when i remove the resistor it switches back to prog1 bankA
> > > >
> > >
> > > Normal ?....
> > >
> > > > I have no idea what could be wrong...could it be IC30 or even
> the
> > > > processor ?? Did you have something simlar ?
> > > >
> > >
> > > I would check/replace the suspective ICs on the panel board first.
> > >
> >
>