Theremin CV output to control Keyboard Exp? > What's in this Pedal ???

[petemoore]

http://www.wwbw.com/Korg-EXP2-Expression-Pedal-i57614.music
  ...expression pedal from Korg, reported to be useful with Triton for controlling expression parameters...
  Any clues yet as to what is in one of these...schematic, Do's 'n don'ts or general information happily welcomed.
  Any clues as to what the Expression pedal input circuit of the Triton responds to...control voltage or variable resistance or..?
  I would like to use the Theremax's CV output to control the keyboard...any advice sorely welcomed [welcomed with eyes that tire of fruitless searches, if I 'can't'...well...it'd just be good to know that or that I 'can'].

[Rodgre]

My guess is that it's just a pot. Most expression pedals are just varying a resistance which varies a voltage that it gets from the expression jack on the device it's controlling. They typically use a TRS jack/cable with which ground is ground, and tip might be voltage coming from the device, and the ring is the "post pot" voltage that you're controlling with the pedal.

Nuthin' fancy at all.

Roger

[petemoore]

just varying a resistance
  Seems like a safe enough place to start.
  Sounds like a pot wired to a TRS jack with the wiper 'in the middle' on the ring.
  I was kind of hoping if it was resistance activated it would be a 2 lug connection..that way I could use a simple LED varying the LDR's resistance when the CV changes it's brightness.