Discussion about the Korg PolySix synthesizer

hello all,

i just picked up a polysix which has some serious issues.  it will
intermittently produce something which almost resembles a proper
sound, but about half the time i get nothing at all.

it has obviously suffered the infamous battery leakage as you can see
in this picture:

http://i67.photobucket.com/albums/h313/botcore/DSC01168.jpg

a new battery has been installed (by somebody before me) but it looks
like that is as far as previous repair attempts have gone.

i have removed the board and will try cleaning it to see what happens,
but before i get into serious repair i'm hoping somebody can tell me
what else i might want to check for so i don't waste the effort only
to find out it wasn't the problem.

any help would be appreciated!

Hello Brian,

I had a similar problem with another P6 which I had in for repair. 
One of the quad latches was running out of control because the 
control port line from the CPU was missing. I see from your picture 
there is still some severe corrosion on the print which needs to be 
dealt with post haste! I would suggest you start looking from broken 
tracks around the area where IC31 is and the new battery has been 
mounted.

Cheers,
Andy


--- In PolySix@yahoogroups.com, "Brian Down" <mathletics@...> wrote:
>
> hello all,
> 
> i just picked up a polysix which has some serious issues.  it will
> intermittently produce something which almost resembles a proper
> sound, but about half the time i get nothing at all.
> 
> it has obviously suffered the infamous battery leakage as you can 
see
> in this picture:
> 
> http://i67.photobucket.com/albums/h313/botcore/DSC01168.jpg
> 
> a new battery has been installed (by somebody before me) but it 
looks
> like that is as far as previous repair attempts have gone.
> 
> i have removed the board and will try cleaning it to see what 
happens,

> but before i get into serious repair i'm hoping somebody can tell me
> what else i might want to check for so i don't waste the effort only
> to find out it wasn't the problem.
> 
> any help would be appreciated!
>

looks nlike there are plenty of corroded (dark colored) tracks radiating out from the battery area....they did the easy part---- i see a lot of rewiring/surgery in your future, but it could come back to life.....wouldnt a simple replacement k-367 be nice?




________________________________

From: Brian Down <mathletics@hotmail.com>
To: PolySix@yahoogroups.com
Sent: Friday, October 31, 2008 1:03:05 AM
Subject: [PolySix] common problems?


hello all,

i just picked up a polysix which has some serious issues. it will
intermittently produce something which almost resembles a proper
sound, but about half the time i get nothing at all.

it has obviously suffered the infamous battery leakage as you can see
in this picture:

http://i67.photobuc ket.com/albums/ h313/botcore/ DSC01168. jpg

a new battery has been installed (by somebody before me) but it looks
like that is as far as previous repair attempts have gone.

i have removed the board and will try cleaning it to see what happens,
but before i get into serious repair i'm hoping somebody can tell me
what else i might want to check for so i don't waste the effort only
to find out it wasn't the problem.

any help would be appreciated! 

 


      

[Non-text portions of this message have been removed]

Basically you should remove the PCB, remove any socketed devices, clean
the board as best you can, solder wire connections wherever there are
damaged tracks, and hope that the ICs have not been compromised.

Knowing which tracks are OK can be tricky. It is good to test these with
an Ohmeter, but be careful of what you are actually measuring, as a PCB
will always have multiple electrical paths.

This kind of fine wire work takes some skill to do well, and done badly
it may cause difficulty with fault finding, as a bad solder joint will
not behave as expected.

If you want to see some examples of this kind of repair job, I'm sure
there will be several examples of similarly repaired PCBs from Poly6s of
forum members. Mine has been repaired twice, though I don't currently
have my synth with me to photograph.

Good luck with it all.

-Oliver

On Fri, 2008-10-31 at 05:19 -0700, steven pistrich wrote:
> looks nlike there are plenty of corroded (dark colored) tracks radiating out from the battery area....they did the easy part---- i see a lot of rewiring/surgery in your future, but it could come back to life.....wouldnt a simple replacement k-367 be nice?
> 
> 
> 
> 
> ________________________________
> From: Brian Down <mathletics@hotmail.com>
> To: PolySix@yahoogroups.com
> Sent: Friday, October 31, 2008 1:03:05 AM
> Subject: [PolySix] common problems?
> 
> 
> hello all,
> 
> i just picked up a polysix which has some serious issues. it will
> intermittently produce something which almost resembles a proper
> sound, but about half the time i get nothing at all.
> 
> it has obviously suffered the infamous battery leakage as you can see
> in this picture:
> 
> http://i67.photobuc ket.com/albums/ h313/botcore/ DSC01168. jpg
> 
> a new battery has been installed (by somebody before me) but it looks
> like that is as far as previous repair attempts have gone.
> 
> i have removed the board and will try cleaning it to see what happens,
> but before i get into serious repair i'm hoping somebody can tell me
> what else i might want to check for so i don't waste the effort only
> to find out it wasn't the problem.
> 
> any help would be appreciated! 
> 
>  
> 
> 
>       
> 
> [Non-text portions of this message have been removed]
> 
> 
> ------------------------------------
> 
> PolySix "Digiest" Page: http://www.acc.umu.se/~amber/Poly6Yahoo! Groups Links
> 
> 
>

Thanks everybody.  I'm planning to work on it this weekend so I'll let
you know how it turns out.  If it proves to be beyond my capabilities
I guess I'll look into a replacement K-367A board.  

-Brian

--- In PolySix@yahoogroups.com, Oliver Fairhall <o.fairhall@...> wrote:
>
> Basically you should remove the PCB, remove any socketed devices, clean
> the board as best you can, solder wire connections wherever there are
> damaged tracks, and hope that the ICs have not been compromised.
> 
> Knowing which tracks are OK can be tricky. It is good to test these with
> an Ohmeter, but be careful of what you are actually measuring, as a PCB
> will always have multiple electrical paths.
> 
> This kind of fine wire work takes some skill to do well, and done badly
> it may cause difficulty with fault finding, as a bad solder joint will
> not behave as expected.
> 
> If you want to see some examples of this kind of repair job, I'm sure
> there will be several examples of similarly repaired PCBs from Poly6s of
> forum members. Mine has been repaired twice, though I don't currently
> have my synth with me to photograph.
> 
> Good luck with it all.
> 
> -Oliver
> 
> 
> On Fri, 2008-10-31 at 05:19 -0700, steven pistrich wrote:
> > looks nlike there are plenty of corroded (dark colored) tracks
radiating out from the battery area....they did the easy part---- i
see a lot of rewiring/surgery in your future, but it could come back
to life.....wouldnt a simple replacement k-367 be nice?
> > 
> > 
> > 
> > 
> > ________________________________
> > From: Brian Down <mathletics@...>
> > To: PolySix@yahoogroups.com
> > Sent: Friday, October 31, 2008 1:03:05 AM
> > Subject: [PolySix] common problems?
> > 
> > 
> > hello all,
> > 
> > i just picked up a polysix which has some serious issues. it will
> > intermittently produce something which almost resembles a proper
> > sound, but about half the time i get nothing at all.
> > 
> > it has obviously suffered the infamous battery leakage as you can see
> > in this picture:
> > 
> > http://i67.photobuc ket.com/albums/ h313/botcore/ DSC01168. jpg
> > 
> > a new battery has been installed (by somebody before me) but it looks
> > like that is as far as previous repair attempts have gone.
> > 
> > i have removed the board and will try cleaning it to see what happens,
> > but before i get into serious repair i'm hoping somebody can tell me
> > what else i might want to check for so i don't waste the effort only
> > to find out it wasn't the problem.
> > 
> > any help would be appreciated! 
> > 
> >  
> > 
> > 
> >       
> > 
> > [Non-text portions of this message have been removed]
> > 
> > 
> > ------------------------------------
> > 
> > PolySix "Digiest" Page: http://www.acc.umu.se/~amber/Poly6Yahoo!
Groups Links

> > 
> > 
> >
>