VVRI trem circuit dead

Discussion in 'Amp Tech Center' started by talpa, Sep 21, 2019.

  1. talpa

    talpa TDPRI Member

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    My '90 (very early unit) '63 Vibroverb Reissue trem circuit has stopped working. To recap:

    * all other amp functions are fine, inc. Reverb
    * All tubes are functioning/glowing
    * guitars play fine thru the amp, just zero trem, no Depth no Speed

    Any idea where to start troubleshooting ?

    I had not fired up the amp in a few months, but the Trem circuit as you owners/users know is top-shelf and don't want to lose that gorgeous sound.

    Thx -
    Jim
     
  2. Fluddman

    Fluddman Tele-Meister

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    I'd start by cleaning/tightening the foot switch connectors and then swapping the tremolo tube for a known good one.
     
  3. Axis29

    Axis29 Poster Extraordinaire Ad Free Member

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    Check the footswitch for continuity, too.
     
  4. BobbyZ

    BobbyZ Doctor of Teleocity

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    Try a different tube in the trem circuit, they often still glow when they don't work. It's also real easy to swap a tube.
     
  5. Boil

    Boil Tele-Holic

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    Is that an optical tremlo?
     
  6. Wally

    Wally Telefied Ad Free Member

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    That is a bias vary trem. Plus one on checking out the tube, which would be V5, and the pedal. Any other problem will be inside.
    If the bias is too hot, that bias vary trem will cease to function. That amp is almost 30.....on might consider capping and doing good general service.
     
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