Filter cap question(s) '68 Twin

Discussion in 'Amps/Cabs Tech Corner: Amplifier, Cab & Speakers' started by strat-rock, Jan 8, 2008.


  1. strat-rock

    strat-rock Member

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    A filter cap I'm replacing is 33uf 450vdc and I can't seem to find another. Is it ok to replace with a higher value, say 40uf?
     
  2. slider313

    slider313 Silver Supporting Member

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    40 would be good. Keep the voltage at 450 or 500.
     
  3. strat-rock

    strat-rock Member

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    Thanks.

    There's also a 22uf I'd like to replace with a 30uf since when I bought the 22uf all I could find was an IC. The rest are Sprague and it'd be nice to go all Sprague.

    The 22uf is the third one over, right next to the 33uf in question and the 33uf is the second over, on the far side, away from the transformer.

    I can't find any of these values for a '68 so I imagine they've been changed out over the years.
     
  4. slider313

    slider313 Silver Supporting Member

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    The first two should be in series and were originally 70uf at 350 volts. I'm not sure if you mean these were replaced with the 33uf? If they were then you should replace them with 100uf at 350 volt, again in series for 50uf and 700 volts. The 22uf's can be replaced with Sprague 20's at 500 volts. Post a picture.
     
  5. strat-rock

    strat-rock Member

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    [​IMG]


    The missing one is where a Mallory paper cap was, and it's value was 20uf/500vdc. The next one over is a 33uf/450vdc. The next is 22uf/500vdc and the last two are both 80uf/450vdc.
     
  6. slider313

    slider313 Silver Supporting Member

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    The first two are fine at 80uf at 450 in series, which gives you 40uf at 900 volts. the next three should be 20uf at 500 and that's what I would replace them with.
     
  7. strat-rock

    strat-rock Member

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