Spare parts for Keystation Pro 88?

[mikeroephonics]

Hi. I own an M-Audio Keystation Pro 88 MIDI controller keyboard. Unfortunately the modwheel is broken. It erratically broadcasts CC mod values when the wheel is at rest. I believe I banged it years ago, but who knows.

I tried using this to clean it, but it didn't help:
http://www.lpslabs.com/product-details/582
It's otherwise a great product for cleaning potentiometers and other electrical parts.

Here's the part I'm looking for, which is out of stock at this vendor:
http://syntaur.com/Items/4851.html

I can't find the part anywhere else on the web and M-Audio discontinued the KSP 88 Pro years ago. It's a great MIDI controller, and I want to prolong its life as long as possible. Any ideas?

Thanks,
Mike

[cyrano]

Are you sure this is a potentiometer?

By the looks of it, it could also be some type of encoder. Does it have "clickstops" when you turn it?

A temporary solution could be to replace each pot with a couple of resistors to stop the sysex messages, if these are pots.

[ivansc]

Almost certainly a BCD encoder.

Have a look at the blue part on yours and see if you can identify the manufacturer & you might well get at the very least a spec out of them.
I would be surprised if you couldnt figure out some sort of replacement.

Oh and of course I assume you already swapped the ribbon cables over on the 2 wheels to make sure it IS just the bcd switch?

[mikeroephonics]

Thanks for the replies. All I've done so far is opened it up once to spray the modwheel assembly with electrical contact spray. That didn't help. I had to reassemble the entire unit to test this since it's basically impossible to test while disassembled.

I opened it up a second time to disconnect the cable from the modwheel assembly (I remapped CC Mod to a vertical fader on the KSP 88 Pro.)

I'm not completely sure if it's a potentiometer or not, but I'm almost certain that something is broken in whatever the mechanism is.

Thanks,
Mike

[cyrano]

If it is an encoder and if it behaves spooky, my bet is on a broken flatcable. If one of the traces breaks, even the slightest movement will produce intermittent contact and the decoder goes haywire...

Have a really close look at the traces. These can be repaired with some conductive ink or glue IF you can find the broken spot.

[ivansc]

...or just paint over all of them. Messy, but pretty much guaranteed to work if that IS the problem.

And he i of course right. BCD encoders dont often go wrong partially. usually it works or it dont sorta thing.