HELP: Fixed Expression Pedal Wiring Diagram?

Discussion in 'Effects, Pedals, Strings & Things' started by MikeMountain, Jun 8, 2015.

  1. MikeMountain

    MikeMountain Member

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    Detroit, MI
    Does anyone know how to build a fixed expression pedal version of a Moog EP-3? My brother has an MF Boost that he uses for bass, and we wanna build a little Hammond 1590A size footswitch that will work as a switchable preset boost for that pedal (expression pedal controls the gain knob). I know we'll need a TRS jack, a switch, and a pot, but I'm not sure what value potentiometer or how to wire it up, or if we can wire an LED to light up when activated (powered from the pedal if possible). Can someone help with a diagram? Thanks!
     
  2. drbob1

    drbob1 Silver Supporting Member

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    How much do you know? The Moog EP is powered from the ring and uses the sleeve as the ground. So, one end lug of the pot goes to sleeve, one to ring and the tip goes to the wiper. The sleeve is bringing in anything from 5-10v, usually +, so you can wire up and LED using that for power with a resistor to limit current.
     
  3. gibs5000

    gibs5000 Member

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    I would help, but dropped the foots witch out before I began my build, realized I didn't really need a preset switch for my delay repeats, so I just wired everything straight to the pot and left the switch out, never did figure out exactly how to do it either, sorry. Count me as interested.
     
  4. MikeMountain

    MikeMountain Member

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    So it sounds like I can wire the tip, ring, and sleeve to individual poles of a 3PDT switch (to activate or deactivate the expression feature) and wire an LED across the ring and sleeve with a 1k resistor for current limiting. Any idea on the pot value the MF Boost will be looking for? 10k? 25k? 50k? Higher than that?
     
  5. gibs5000

    gibs5000 Member

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    A 10k should be fine
     

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