Discussion about the Korg PolySix synthesizer

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

Are you refering to the trimpot on the computer board ?

I don't know very much about it but on my Trident it did the same 
when I set it to a cetrain position. This is how it was when I first 
got it - powered it up and all banks/presets lite up. By ritating the 
trimmer a bit it booted up correctly finally (bank 1 / preset 1)


--- 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
>

Hm I cleaned up all the trimpots....

I rather would like to know which IC could be wrong

thanks a lot for reply....

Gregor

> Are you refering to the trimpot on the computer board ?
> 
> I don't know very much about it but on my Trident it did the same 
> when I set it to a cetrain position. This is how it was when I first 
> got it - powered it up and all banks/presets lite up. By ritating the 
> trimmer a bit it booted up correctly finally (bank 1 / preset 1)
> 
> 
> --- 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
> >
> 
> 
> 
> 
> 
> 
> 
> PolySix "Digiest" Page: http://www.acc.umu.se/~amber/Poly6 
> Yahoo! Groups Links
> 
> 
> 
>  
> 
> 



	

	
		
___________________________________________________________ 
Telefonate ohne weitere Kosten vom PC zum PC: http://messenger.yahoo.de

Hi all,

Tested the CPU on TP4 get pulse of 10ms width..??
I also tested the signals on TP2 / TP3(GND) and i get corresponding
changes for all the knobs except MG delay / level
and all the EG knobs....

does this mean my processor is damaged??

I really would appreciate some help

thanks 

Gregor  
>
> Hm I cleaned up all the trimpots....
> 
> I rather would like to know which IC could be wrong
> 
> thanks a lot for reply....
> 
> Gregor
> 
> > Are you refering to the trimpot on the computer board ?
> > 
> > I don't know very much about it but on my Trident it did the 
same 
> > when I set it to a cetrain position. This is how it was when I 
first 
> > got it - powered it up and all banks/presets lite up. By 
ritating the 
> > trimmer a bit it booted up correctly finally (bank 1 / preset 1)
> > 
> > 
> > --- 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
> > >
> > 
> > 
> > 
> > 
> > 
> > 
> > 
> > PolySix "Digiest" Page: http://www.acc.umu.se/~amber/Poly6 
> > Yahoo! Groups Links
> > 
> > 
> > 
> >  
> > 
> > 
> 
> 
> 
> 	
> 
> 	
> 		
> ___________________________________________________________ 
> Telefonate ohne weitere Kosten vom PC zum PC: 
http://messenger.yahoo.de
>

> 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.

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.
> >
>

Hi all,

there are three IC on the panel boards (369 and 370)
one 4556D which is an oamp as i found out this one is for the volume
knob i think...and two 14051. These are multiplexers..so they could be
the reason for the strange behavior...I'll check them...as soon as i
get the osciloscope..Does anyone know where to get the 14051 chaep in
germany ???

See ya all

Gregor

So long  

>
> 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.
> > >
> >
>