Archive of the former Yahoo!Groups mailing list: Discussion about the Korg PolySix synthesizer

Hey guys! Thanks again for providing these KLM367 boards! Um, so yeah... I just finished populating my new KLM367 clone board and I'm having trouble.

I'm pretty sure that the trouble is somewhere in the factory MIDI board but I can't figure out the troubleshooting sequence or parts I might need to get this midi kit going again.

Here's my dillema:

I populated the board (KLM367 Clone) and omitted IC32 because the MIDI kit from the old board didn't have that IC either. It looks like it wasn't needed. The midi Kit jumpers the VCC battery line and the CS line. The MIDI kit also makes other jumpers to random multiplexers and demultiplexers throughout the unit.

After power up, all I got was lights A, 1, and POLY to come on. There is no response if I press the buttons.

I got through the reset circuit calibration.

I couldn't get through the D/A adjustment. I reset the jumpers and noticed that the stupid EPROM IC's weren't pushed in all of the way!!!!!! (Probably a fatal error).

After pushing in the EPROMS and resetting the sockets on the MIDI board, I got the D/A adjustment lights to come on. I twirled the little trimmers until I got dizzy but couldn't get the one on the right to move; it was stuck on 4.

After checking further into the unit, Port 11 on the CN10 and CN06 is stuck at ground. I checked continuity from the CPU to the connections and it tested OK. Following the traces indicated that Port 11 doesn't really go anywhere except out of the CPU and into the CN06 and CN10 jacks.

Removing CN06 to test will fudge up the data lines because the spare multiplexer ports on the KLM369 4051 are being used for some midi board function.

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Does anybody have suggestions or ideas? I think that I'm going to purchase IC32 and a new CPU and see if I can get the board to work without the MIDI kit.

Does anyone have the ROM files or knowledge of the midi kit if it isn't trashed?

-Mike