[sdiy] Hacking the expression pedal input on a JD-800

[WeAreAs1 at aol.com]

In a message dated 2/19/04 10:58:27 AM, david.k.cornutt at boeing.com writes:

<< So the question is: has anyone opened up a Roland 

expression pedal?  Does it consist of just a pot, or is

there active circuitry in it? >>

Hello David,

The Roland EV-5 pedal is simply a pot that's wired directly to the three 
terminals of the 1/4" TRS plug (there's second pot that's also in there to set the 
"minimum value", but it can be eliminated for your purpose).  I don't have 
the schematic handy, but a 50K pot value seems to come to mind.  I'm pretty sure 
the pot has custom taper that's designed to match the throw of the pedal (the 
EV-5 still has a terrible feel, though).  I'll look around and see if I can 
find the schematic.

Michael Bacich