Korg Polysix: dead or alive KLM367 board needed

[perfectdefect]

I bought a Polysix on eBay for a very reasonable price, it was one of those "I found this in my grandmothers attic, not sure how to plug the cord into the wall" deals. I assumed it would arrive with a really bad case of battery corrosion to the board, and my plan was to use it as an excuse to learn how to repair traces. It arrived and is in beautiful shape, but the KLM367 board is simply missing. Everything else looks fine, all chips are present etc. I know there are such things as the Kiwi six, Old Crows repro board and synth prof's repro boards, but dang, I want to learn how to repair traces.

Anyone have a damaged KLM367 board laying around they want to let go of?

[sam]

I have repaired countless battery boards....unless you are lucky to find a battery board with minimal damage I would not recommend taking on this task as a learning experience....

Go for the kiwi six and learn on something else...you will gain experience fitting it yourself.

[pflosi]

Yeah, I agree... I have a busted KLM367 somewhere around here. We first tried to repair some traces, then it would randomly work and then do strange things again. In the end I replaced it with one of the clones (that AFAIK don't exist anymore?). I could totally send you the busted PCB, but I doubt you'd be able to get it to work and it's also missing some components since we had to salvage a few of them...

[garranimal]

same here. Know that this can be one of the most frustrating repair experiences you can inflict upon yourself. My ps-6 has more than bad trace problems. Intermittent cold solder joints. The connector pins and molex tabs are also oxidized. I had a few connector pins simply break off when removing the connector, so those pins had to be replaced. Not to mention the oxidation can travel INSIDE of semiconductors to make them behave erratically. The synth has been somewhat useable now. I've used it on a track already, but wish the other problems were solved.

I went through every single connector and trace in a long, drawn out time period of two or three weeks. I printed the schematic and highlighted every single connection that was good and put a red X on every bad connection. Instead of retracing the really long runs, I went about jumping a few connections w/ wire. My synth went from being non-functional to about 75%, but not quite reliable still. Some of the bugs are not being able to select all waveforms, sub osc not selecting properly, MG section does whatever it wants to do, programs not saving correctly, and the ensemble section always defaults to some setting. I am currently saving up for the Kiwi upgrade.

The bright side of my unit, ALL THE KEYS WORK PERFECTLY! It has been case stored most if not all its life.

[perfectdefect]

I appreciate y'alls input. I'm a few months of tinkering into a Polymoog and have had the same 2 steps forward, 3 steps sideways, 5 back type experience you describe with it.

I am indeed tempted by the kiwisix, but the price has me put off at the moment, and I especially don't want to get one and find out this board has some other issues...

Maybe the clone?... hmmm. I read there is a component -thermistor I think that you have to get from an original board. Anyone know about this?

[sam]

You really need an old board to complete the clone ..the connectors and some hard to find components.

I am in the process of making one...I do have a box full of boards that might of survived if done properly.

Some tips.

Don't attempt to de solder ic31 or any other chip...cut it out and carefully remove the legs.

Really clean the board.'.with isopropyl alcohol.

Be patient....

[leonidspaul]

Hi, there´s someone selling one now in Madrid if it helps. http://www.hispasonic.com/anuncios/plac ... six/286201
Paul