expression pedal wiring

[crittoprrr]

Hey guys, I just bought a Yamaha EP-1 expression pedal for a boss Pitchshifter I own, but it is rather bizarre, it only works at the very bottom of the range of motion of the pedal. I'm trying to figure out what's wrong with it, but I can tel you the pot rates about 60k. If it needs a new expression potentiometer, where might I get one?

[549]

[crittoprrr]

I've done some tinkering. The stock value of the pot is actually 20k. I need one that will be about 300k.

Now, before I look dumb asking where I can find a pot, I should tell you all I've never seen a pot like this before. It has a lever on it that the rocker pedal presses down upon to change the resistance. If I had a digital cam I'd show you.

Anyway, where can I find one of these unusual looking pots?

[ethrbunny]

Ive been curious about this concept for a while. There is a post on commonsound.org about using an expression pedal. The drawing there makes it look like its run in parallel with the existing pot. Seems like you would always have to be sure to turn the existing pot to zero before you plug in the pedal otherwise you'd get some odd amalgam of the two resistances.

[Greybeard]

I added an expression pedal to a DOD FX-65 I modded. I used a stereo jack that disconnects the normal speed pot when the pedal is pluged into it. So without the expression pedal the chorus works normally. When I plug in the expression pedal the chorus speed control is "replaced" by the pot in the pedal. Works great.

Greybeard

[ethrbunny]

How did you wire that? Is it a standard stereo jack or something special?