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Korg POLY-61 pitch drift problem

Korg POLY-61 pitch drift problem

2008-06-04 by plastikanimal

Hi, I'm trying to repair a POLY-61 for a friend. I have very little
0;experience at this.(I replaced the battery in mine so he thinks I'm a
;
genius).
Anyway, I replaced his battery,but some of the ni-cad acid found it's
way across to the voice board. I had to replace a transistor and some
other things. I thought I had it right, but after a few minutes voice
2 and 3 begin to drift up in pitch to no end. I don't know if I used
the wrong parts or if something else is wrong.

Any ideas?

RE: [vintagesynthrepair] Korg POLY-61 pitch drift problem

2008-06-04 by Brian Davies

How did you clean off the battery acid?
 
Regards
Brian G3OYU
www.g3oyu.co.uk
 
  _____
Show quoted textHide quoted text
From: vintagesynthrepair@yahoogroups.com
[mailto:vintagesynthrepair@yahoogroups.com] On Behalf Of plastikanimal
Sent: Wednesday, 04 June 2008 08:26
To: vintagesynthrepair@yahoogroups.com
Subject: [vintagesynthrepair] Korg POLY-61 pitch drift problem
 
Hi, I'm trying to repair a POLY-61 for a friend. I have very
little
experience at this.(I replaced the battery in mine so he
thinks I'm a
genius).
Anyway, I replaced his battery,but
some of the ni-cad acid found it's
way across to the voice board. I
had to replace a transistor and some
other things. I thought I had
it right, but after a few minutes voice
2 and 3 begin to drift up
in pitch to no end. I don't know if I used
the wrong parts or if
something else is wrong.

Any ideas?
 



E-mail message checked by Spyware Doctor (5.5.0.178)
Database version: 5.09970
http://www.pctools.com/Spyware-Doctor/

Re: [vintagesynthrepair] Korg POLY-61 pitch drift problem

2008-06-04 by Frank Simon

That happened on a Korg Trident II for me and I had to re route some of the PC board traces with wire because it fried the board.
Show quoted textHide quoted text
----- Original Message -----
Sent: Wednesday, June 04, 2008 5:02 AM
Subject: RE: [vintagesynthrepair] Korg POLY-61 pitch drift problem

How did you clean off the battery acid?

Regards

Brian G3OYU

www.g3oyu.co.uk

From: vintagesynthrepair@yahoogroups.com [mailto:vintagesynthrepair@yahoogroups.com] On Behalf Of plastikanimal
Sent: Wednesday, 04 June 2008 08:26
To: vintagesynthrepair@yahoogroups.com
Subject: [vintagesynthrepair] Korg POLY-61 pitch drift problem

Hi, I'm trying to repair a POLY-61 for a friend. I have very little 
experience at this.(I replaced the battery in mine so he thinks I'm a genius). Anyway, I replaced his battery,but some of the ni-cad acid found it's way across to the voice board. I had to replace a transistor and some other things. I thought I had it right, but after a few minutes voice 
2 and 3 begin to drift up in pitch to no end. I don't know if I used the wrong parts or if something else is wrong. 
 Any ideas?




E-mail message checked by Spyware Doctor (5.5.0.178)
Database version: 5.09970
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Re: Korg POLY-61 pitch drift problem

2008-06-04 by plastikanimal

I used soap and water on the cpu board. The voice board didn't seem to

have any acid on it except in one spot where the acid seemed to move
along the "jumper ribbon". I cleaned that with a Q-tip,soap and water.
It ended up eating traces for a couple of capacitors and a transistor.
The "high" and "bend" adjustments are just below this spot so maybe
it's gotten to them as well.
--- In vintagesynthrepair@yahoogroups.com, "Brian Davies" <brian@...>
wrote:
&#10;>
> How did you clean off the battery acid?
>  
&#10;> Regards
> Brian G3OYU
> www.g3oyu.co.uk
>  
>   _____  
> 
> From: vintagesynthrepair@yahoogroups.com
> [mailto:vintagesynthrepair@yahoogroups.com] On Behalf Of plastikanimal
> Sent: Wednesday, 04 June 2008 08:26
> To: vintagesynthrepair@yahoogroups.com
> Subject: [vintagesynthrepair] Korg POLY-61 pitch drift problem
>  
> Hi, I'm trying to repair a POLY-61 for a friend. I have very
> little
;experience at this.(I replaced the battery in mine so he
> thinks I'm a
genius).
Anyway, I replaced his
battery,but
> some of the ni-cad acid found it's
way across to the voice
board. I
> had to replace a transistor and some3;
other things. I
thought I had
> it right, but after a few minutes voice
2 and 3 begin to
drift up
> in pitch to no end. I don't know if I used
the wrong parts
&#10;or if
> something else is wrong.

Any ideas?
Show quoted textHide quoted text
>  
> 
> 
> 
> E-mail message checked by Spyware Doctor (5.5.0.178)
> Database version: 5.09970
> http://www.pctools.com/Spyware-Doctor/
>

RE: [vintagesynthrepair] Re: Korg POLY-61 pitch drift problem

2008-06-04 by Brian Davies

You need to neutralize the acid , the chemical I use is bicarbonate of soda,
a teaspoonful in a glass of warm water will work.  Then rinse with warm
water, dry thoroughly before powering up.
 
73
Brian G3OYU
www.g3oyu.co.uk
www.surreyraynet.net
 
  _____
Show quoted textHide quoted text
From: vintagesynthrepair@yahoogroups.com
[mailto:vintagesynthrepair@yahoogroups.com] On Behalf Of plastikanimal
Sent: Wednesday, 04 June 2008 18:46
To: vintagesynthrepair@yahoogroups.com
Subject: [vintagesynthrepair] Re: Korg POLY-61 pitch drift problem
 
I used soap and water on the cpu board. The voice board didn't seem
to
have any acid on it except in one spot where the acid seemed to
move
along the "jumper ribbon". I cleaned that with a Q-tip,soap
and water.
It ended up eating traces for a couple of capacitors and
a transistor.
The "high" and "bend" adjustments are just below this
spot so maybe
it's gotten to them as well.
--- In
vintagesynthrepair@ <mailto:vintagesynthrepair%40yahoogroups.com>
yahoogroups.com, "Brian Davies"
<brian@...>
wrote:
>
> How did you clean off the
battery acid?
> 
> Regards
> Brian
G3OYU
> www.g3oyu.co.uk
> 
> _____ 
>

> From: vintagesynthrepair@
<mailto:vintagesynthrepair%40yahoogroups.com> yahoogroups.com
>
[mailto:vintagesynthrepair@ <mailto:vintagesynthrepair%40yahoogroups.com>
yahoogroups.com] On Behalf Of plastikanimal
> Sent: Wednesday, 04
June 2008 08:26
> To: vintagesynthrepair@
<mailto:vintagesynthrepair%40yahoogroups.com> yahoogroups.com
>
Subject: [vintagesynthrepair] Korg POLY-61 pitch drift problem
>

> Hi, I'm trying to repair a POLY-61 for a friend. I have
very
> little
experience at this.(I replaced the battery
in mine so he
> thinks I'm a
genius).
Anyway, I
replaced his
battery,but
> some of the ni-cad acid found
it's
way across to the voice
board. I
> had to
replace a transistor and some
other things. I
thought I
had
> it right, but after a few minutes voice
2 and 3
begin to
drift up
> in pitch to no end. I don't know if I
used
the wrong parts
or if
> something else is
wrong.

Any ideas?
> 
> 
>

> 
> E-mail message checked by Spyware Doctor
(5.5.0.178)
> Database version: 5.09970
>
http://www.pctools. <http://www.pctools.com/Spyware-Doctor/
>
com/Spyware-Doctor/
>

 



E-mail message checked by Spyware Doctor (5.5.0.178)
Database version: 5.09970
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Re: Korg POLY-61 pitch drift problem

2008-06-04 by plastikanimal

Thanks Brian! I will check into it.
--- In vintagesynthrepair@yahoogroups.com, "Brian Davies" <brian@...>
wrote:
>
;> You need to neutralize the acid , the chemical I use is bicarbonate

of soda,
> a teaspoonful in a glass of warm water will work.  Then rinse with warm
> water, dry thoroughly before powering up.&#13;
>  
> 73
> Brian G3OYU
> www.g3oyu.co.uk
> www.surreyraynet.net
>  
>   _____  
0;> 
> From: vintagesynthrepair@yahoogroups.com
> [mailto:vintagesynthrepair@yahoogroups.com] On Behalf Of plastikanimal
> Sent: Wednesday, 04 June 2008 18:46
> To: vintagesynthrepair@yahoogroups.com
> Subject: [vintagesynthrepair] Re: Korg POLY-61 pitch drift problem
>  
> I used soap and water on the cpu board. The voice board didn't seem
> to
have any acid on it except in one spot where the acid
seemed to
> move
0;along the "jumper ribbon". I cleaned that with a
Q-tip,soap

> and water.
It ended up eating traces for a couple of
&#10;capacitors and
> a transistor.
The "high" and "bend" adjustments are just
below this
> spot so maybe
it's gotten to them as well.
--- In
> vintagesynthrepair@ <mailto:vintagesynthrepair%40yahoogroups.com>
> yahoogroups.com, "Brian Davies"
> <brian@>
wrote:
>
> How did you clean off the
> battery acid?
> 
> Regards
> Brian
> G3OYU
> www.g3oyu.co.uk
> 
> _____

>
> 
> From: vintagesynthrepair@
> <mailto:vintagesynthrepair%40yahoogroups.com> yahoogroups.com
>
> [mailto:vintagesynthrepair@
<mailto:vintagesynthrepair%40yahoogroups.com>
> yahoogroups.com] On Behalf Of plastikanimal
> Sent:
Wednesday, 04
> June 2008 08:26
> To: vintagesynthrepair@
> <mailto:vintagesynthrepair%40yahoogroups.com> yahoogroups.com
>
> Subject: [vintagesynthrepair] Korg POLY-61 pitch drift
problem
>
> 
> Hi, I'm trying to repair a POLY-61 for a friend. I have
> very
> little
experience at this.(I replaced the
battery
> in mine so he
> thinks I'm3;
a
genius).
Anyway, I
> replaced his
&#10;battery,but
> some of the ni-cad acid
found
> it's
way across to the voice
board. I
>
&#10;had to
> replace a transistor and some
other things.&#13;
I
thought I
> had
> it right, but after a few minutes voice
2 and 3
> begin to
drift up&#13;
> in pitch to no end. I don't
know if I
> used&#13;
the wrong parts
or if
> something
else is
> wrong.

Any ideas?
Show quoted textHide quoted text
> 
> &#13;
>
> 
> 
> E-mail message checked by Spyware Doctor
> (5.5.0.178)
> Database version: 5.09970

>
> http://www.pctools. <http://www.pctools.com/Spyware-Doctor/
>
> com/Spyware-Doctor/
>

>  
> 
> 
> 
> E-mail message checked by Spyware Doctor (5.5.0.178)
> Database version: 5.09970
> http://www.pctools.com/Spyware-Doctor/
>

Re: Korg POLY-61 pitch drift problem

2008-06-05 by plastikanimal

Well I played with it some more and it seems that when in "poly mode"
&#10;voices two and three in DCO1 play (with increasing pitch)while the

others are only audible with the square wave. DCO2 plays all voices3;
fine but 2&3. 
So it's confused by 2&3. But why?
--- In vintagesynthrepair@yahoogroups.com, "plastikanimal"
<plasticanimal1@...> wrote:
>
> Thanks Brian! I will check into it.
--- In
vintagesynthrepair@yahoogroups.com, "Brian Davies"
<brian@>
wrote:
>
> You need to neutralize
the acid , the chemical I use is bicarbonate
of&#13;
soda,
> a teaspoonful in a glass of warm water will work. 
Then rinse with warm
> water, dry thoroughly before powering
up.
>  
> 73
> Brian G3OYU
0;>
www.g3oyu.co.uk
> www.surreyraynet.net
> 3;

>   _____  
> 
> From:
vintagesynthrepair@yahoogroups.com
>
[mailto:vintagesynthrepair@yahoogroups.com] On Behalf Of
plastikanimal
> Sent: Wednesday, 04 June 2008
18:46
> To: vintagesynthrepair@yahoogroups.com
>
Show quoted textHide quoted text
Subject: [vintagesynthrepair] Re: Korg POLY-61 pitch drift
problem
>  
> I used soap and water on the cpu
board. The voice board didn't seem
> to
&#10;have any
acid on it except in one spot where the acid
seemed
to
> move
along the "jumper ribbon". I cleaned that
with a
Q-tip,soap
> and water.
&#10;It ended up
eating traces for a couple of
capacitors and
> a
transistor.
The "high" and "bend" adjustments are
just
below this
> spot so maybe
0;it's gotten
to them as well.
--- In
> vintagesynthrepair@
<mailto:vintagesynthrepair%40yahoogroups.com>
;>
yahoogroups.com, "Brian Davies"
>
<brian@>3;
wrote:
>
> How did you clean off
the

> battery acid?
> 
> Regards
>
Brian
> G3OYU
> www.g3oyu.co.uk
>

0;> _____

>
> 
> From:
vintagesynthrepair@
>
<mailto:vintagesynthrepair%40yahoogroups.com>
yahoogroups.com
>
>
[mailto:vintagesynthrepair@
<mailto:vintagesynthrepair%40yahoogroups.com>
&#10;>
yahoogroups.com] On Behalf Of plastikanimal
>
&#10;Sent:
Wednesday, 04
> June 2008 08:26
> To:&#13;
vintagesynthrepair@
>
<mailto:vintagesynthrepair%40yahoogroups.com>
yahoogroups.com
>
> Subject: [vintagesynthrepair]
Korg POLY-61 pitch drift
problem
;
>
>

> Hi, I'm trying to repair a POLY-61 for a friend. I
have
> very
> little
experience at this.(I
replaced the
battery
> in mine so he
>
thinks I'm
a
genius).
&#10;Anyway, I
>
replaced his
battery,but
;> some of the ni-cad
acid
found
> it's
;way across to the
voice
board. I
>
had to
> replace
a transistor and some
other
&#10;things.
I
thought I
> had
> it
&#10;right, but after a few minutes voice
2 and 3
> begin&#13;
to
drift up
> in pitch to no end. I
don't
know if I
> used
the wrong
parts
;
or if
> something
else is
>
wrong.

Any ideas?
> 
>

>
> 
> 
> E-mail message checked
by Spyware Doctor
> (5.5.0.178)
> Database version:
5.09970
>
> http://www.pctools.
<http://www.pctools.com/Spyware-Doctor/
>
>
com/Spyware-Doctor/
;
>

>  
>

> 
> 
> E-mail message checked by Spyware
Doctor (5.5.0.178)&#13;
> Database version: 5.09970
>
http://www.pctools.com/Spyware-Doctor/
>

>

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