Cap value range and the compensating for hard to find values question.

Discussion in 'Amps/Cabs Tech Corner: Amplifier, Cab & Speakers' started by jh45gun, Jul 31, 2008.

  1. jh45gun

    jh45gun Member

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    OK since I have found my self messing with older gear I have noticed that some of the caps you may not find that value anymore expecially in the high voltage ranges used in tubes. SO How far off can you be and still be close enough.

    I plan on replaceing the caps in this Bogen MX 60 PA head as I go along. first caps that will be replaced will be the 40 mfd 300 VDC caps that are coming off the rectifers. OK that one is not bad it is a common cap and I suspect I will just use instead of the cardboard can type that is in there some plastic covered aluminum ones that have the leads out both sides as I can get them from my tech friend. However one can a 4x multi is 20 20 mfd /450 vdc 10 10 mfd /350 vdc in my amp which on the schematic is 20 20 20 20 mfd with the first two again 450 and the last two 350 and the schematic said that some amps may have either configuration. So I would suspect the 20x4 would be easier to find. Same with a 5 5 5 5 Mf with the Voltage rated at 200 vdc can in this amp I would suspect that might not be easy to find so I might have to go with a higher value MF can so what can ya get by with and I suppose higher is better in both MF and Volts.
     
  2. SatelliteAmps

    SatelliteAmps Member

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    Actually you can find all of those value in a can capacitor, but they are more expensive than using individuals. Try Antique Electronic Supply www.tubesandmore.com

    All a multi-section can cap is, is multiple individual caps in one container, usually with a common ground. You can use individuals in it's place. So if you can get two 20mfd @ 450v, and two 10mfd @ 350v as individual cap's you can just use those instead. Tie their grounds all together, and their hots go to the normal places in the amp. If you want it to look pretty, you can shrink wrap the whole thing together. You might also have to use a zip tie or something to keep the caps from moving around.
     
  3. CitizenCain

    CitizenCain Member

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    Yep, try Antique Electronics or Weber. I know I saw a 4x20 can when I was looking for cap cans on my Heathkit project.
     
  4. RedRock

    RedRock Member

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    Mouser Electronics sells a 4.7 mfd 250 volt cap for 17 cents each.
    Catalog Number:
    140-HTRL250v4.7-RC
    Their phone number is:
    1-800-346- 6873. These are individual radial caps. Both wires come out of one end. These could be used for your 5 mfd caps.
     
  5. SatelliteAmps

    SatelliteAmps Member

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    17 cents is really hard to beat. If you prefer axial, those aren't much more either.
     
  6. jh45gun

    jh45gun Member

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