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Subject: Re: [PolySix] Re: Help! Repairing a Polysix with burst battery (sound demo + photos!)

From: "Chromatest J. Pantsmaker" <chromatest@azburners.org>
Date: 2013-08-07

A debugging rule that people overlook is that not only do you want to
check "low-resistance" continuity between your points (your DMM's
"beep" might trigger like this, they vary), but you want to make sure
that there is ∗NO∗ continuity between neighboring traces. Sometimes,
a neighboring trace might be on the other side of the board. Luckily,
these boards are only 2-sided!

Here's the schematics:
http://www.chromatest.net/POLY6_Service_Ensemble.pdf

Good luck!

-chromatest

On Wed, Aug 7, 2013 at 5:47 AM, Djé <onoffart@orange.fr> wrote:
> Hi Steve,
> The D(SW12) and 4(SW18)Switches uses the same line in the Programmer matrix, identified P13, Pin-5 of CN10 welded to the KLM-371(programmer board)
> On the KLM-371 between the SW15(PROGRAM-1) & the SW16(PROGRAM-2) you have a Fixing screw.
> The P13 trace pass just above,
> removed this screw and turn on the P6 on says us !
> All the Best
> Djé
>
> --- In PolySix@yahoogroups.com, "traxus12" <ocguitar@...> wrote:
>>
>> Sorry, some of my formatting didn't make it through to the final post. I meant to include these.
>>
>> sound demo:
>> https://soundcloud.com/ocguitar/korg-polysix-death-sounds
>>
>> Bank D and Program 4 constantly illuminated:
>> http://imgur.com/TFEPUPB
>>
>> Thank you! Any advice would be appreciated.
>> -Steve
>>
>> --- In PolySix@yahoogroups.com, "traxus12" <ocguitar@> wrote:
>> >
>> > Hello! I picked up a Korg Polysix recently and I've been trying to bring
>> > it back to life. Nothing I've done has changed anything yet so I'm at a
>> > bit of an impasse and I'm hoping someone out there might be able to help
>> > me narrow down what I should do next. I know how to use a soldering iron
>> > but I'm a complete beginner at repairing circuit board traces.
>> >
>> > Let me give you the symptoms.
>> >
>> > 1. It sounds like it's gone absolutely mental with constant oscillation
>> > and other insanity going on from the moment I power it up.
>> > 2. The Bank D and Program 4 buttons are constantly illuminated after
>> > powering up.
>> >
>> > After cleaning up most of the corrosion I could find around the battery,
>> > it really didn't look as bad as I thought it might so I went ahead and
>> > just installed a Lithium battery holder (using Old Crow's guide) and
>> > tried powering up again. Nothing changed.
>> >
>> > After that, I went back in and removed the IC31 chip (74LS08) and tested
>> > all the traces in the area with a multimeter. Every trace I tested gave
>> > me a happy little beep, even the uglier looking ones that were near the
>> > old battery, so I went ahead and soldered in a new socket and 74LS08
>> > chip at IC31. Powered up. Nothing changed.
>> >
>> > Now, I'm not sure what to do. Did I miss a trace? Should I put jumper
>> > wires on the ugly looking traces even if my multimeter says they're
>> > conducting just fine? Should I replace the other ICs that were near the
>> > battery like IC30 even if they look fine?
>> >
>> > I recorded a sound demo. For the first 40 seconds I don't touch a thing,
>> > then I start to experiment:
>> >
>> >
>> > Bank D and Program 4 constantly illuminated:
>> >
>> >
>> > First sight:
>> > <http://imgur.com/Wv173WQ>
>> >
>> > After initial cleanup:
>> > <http://imgur.com/M8POlkz>
>> >
>> > Installed battery:
>> > <http://imgur.com/Pj3kDFT>
>> >
>> > Replaced IC31:
>> > <http://imgur.com/Nab9GYz>
>> >
>> >
>> >
>> >
>> > [Non-text portions of this message have been removed]
>> >
>>
>
>
>
>
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