Selmer Treble & Bass issue

Discussion in 'Amps/Cabs Tech Corner: Amplifier, Cab & Speakers' started by louderock, Sep 1, 2008.

  1. louderock

    louderock Member

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    1967 Treble & Bass 50. The amp turns on but the tubes never light up. There is no standby switch. Amp has worked perfectly for years until yesterday. Never had an amp where the tubes won't light up at all. Both fuses are good. Any ideas?
     
  2. SatelliteAmps

    SatelliteAmps Member

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    Great amp. If the tubes aren't lighting up at all, there are a few immediate possible problems. One is a bad tube somewhere, shorting out the filaments (also check the pilot lamp, which runs off the same supply). Second would be a wire that came loose or broke. Third would be bad transformer.

    I would also triple check the fuses. They can look ok, but be broken at an end and might not be working correctly.
     
  3. louderock

    louderock Member

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    Thanks. The pilot lamp does work and I checked the fuses with a continuity tester. Maybe I'll swap out a few EL34's and see what happens. Hope the transformer is okay. The original power trans was a partridge but operated at 220. It was replaced with a Mercury Magnetics at 120V.
     
  4. brad347

    brad347 Member

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    There might be other fuses besides the mains fuse. Try replacing ALL fuses, including any inside the amp chassis (may not be visible), installing only the preamp tubes, and see if those light.
     
  5. louderock

    louderock Member

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    cool. I'll open it up and see if there are more fuses. There were 2 on the back - Main & HT. Both are good.
     
  6. brad347

    brad347 Member

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    If there were two on the back, that's probably all the fuses there are.

    But when you open it, you might see a filament wire disconnected. That would cause your tubes to not light.
     
  7. SatelliteAmps

    SatelliteAmps Member

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    Those are the only two fuses.
     

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