Vox AC15 suddenly does not work

Discussion in 'Glowing Bottle Tube Amp Forum' started by David Meiland, May 9, 2021.

  1. David Meiland

    David Meiland Tele-Meister Silver Supporter

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    I have a UK made AC15 that sounded great yesterday (and daily for the last year+) but is silent today. The pilot light comes on but it doesn't make a whisper. I pulled the chassis and the only tube that's lit is the rectifier, everything else is dark. I poked around a little more and noticed that one of the fuses is blown. Obviously I'll replace the fuse and see what happens... don't have one handy now... but any thoughts on what could have happened?
     
  2. ThermionicScott

    ThermionicScott Poster Extraordinaire

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  3. David Meiland

    David Meiland Tele-Meister Silver Supporter

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    It's fuse F1. The schematic shows T4A and the actual fuse says T4L on it. Google seems to say lots of fuses have the A and maybe the L too.
     
  4. DougM

    DougM Poster Extraordinaire

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    One of the tubes may have shorted and took out the fuse. It's kind of unlikely that a preamp tube would do that, so it's most likely a power tube if that's what caused it to blow. Do you have any spare EL84s?
     
  5. MuddyWolf

    MuddyWolf Tele-Meister

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    Voxes run hot and burn up tubes. Replace them every 6 months or go through this again. Lucky that el84s are very inexpensive.
     
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  6. AJBaker

    AJBaker Friend of Leo's

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    It might just be the fuse, or there might be an underlying issue, it's hard to say.

    What year is it from?
     
  7. stepvan

    stepvan Tele-Afflicted Silver Supporter

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    Sounds like a tube may have failed. Replace the tubes (AND FUSE) and see if the problem persists,
     
  8. Dacious

    Dacious Poster Extraordinaire

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    Before you hung new tubes in, replace the fuse and fire it up with no power tubes, make sure the fuse doesn't blow again. If it does, tech time.
     
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