Dunlop Rotovibe reverse the speed control

Discussion in 'Luthier's Guitar & Bass Technical Discussion' started by chubs, May 22, 2008.

  1. chubs

    chubs Member

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    I am lloking to reverse the speed control on my rotovibe... I think the design is crappy because when you click the pedal "ON" it's at full speed vibrato and you back off the speed after... sounds lame when playing live...

    So is there a way... (or a schematic of this thing...) that I could reverse the speed control so that when I stomp on the pedal and it's full forward, the vibrato is at it's slowest... and when i back off... it speeds up to max when full up??


    Thanks
     
  2. Jim Jones

    Jim Jones Member

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    Just swapping the wires on the outer lugs of the speed pot should do that. Depending on the taper of the pot the sweep might feel a little wonky. You might be able to rectify that with some tapering resistors though. There's a great article on the subject over at RG Keen's site, http://www.geofex.com

    Hope this helps!

    Jim
     
  3. chubs

    chubs Member

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    I tried that... it made no diff. . There are only 2 wires on the pot... which I inverted and the effect stayed the same... wierd....
     
  4. Jim Jones

    Jim Jones Member

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    Oh, sorry, so the speed pot is wired up as a variable resistor, not a voltage divider. Are there three lugs on the pot or just two?

    Jim
     
  5. chubs

    chubs Member

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    Maybe someone can help me with this... the pedal is at my rehearsal space....
     
  6. Jim Jones

    Jim Jones Member

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    If it's wired up with a standard pot (and I assume it would be), try moving the wire that's on the "outside" lug to the other outside lug, leaving the wire on the middle lug where it is. That should do it but you may have some taper issues.

    Jim
     

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