Sourcing 20µF 200VAC non-polarized capacitor

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I’m currently trying to fix an old vacuum tube record player from the 1950’s that isn’t working because the capacitors have all dried up and lost their capacitance. There are four capacitors total, and all the other components are good (the motor runs, the tube is OK, the needle cartridge is putting out the right signals, etc.).

However, I’m having trouble sourcing some of the replacement capacitors.

The are four capacitors total that are all rated for 400VAC. The two smaller ones are both less than 1µF and I have had no trouble finding modern capacitors of the same capacitances with similar or better voltage ratings (albeit surface-mount, but that isn’t a problem as I can solder that) for dirt-cheap online (<$1 each).

The two larger ones are giving me more trouble finding them. Here are the original capacitors’ ratings:

  • 20µF, 400VAC, non polarized
  • 80µF, 400VAC, non polarized

The 80µF one was literally impossible to find any that both had the same ratings and would fit. All I could find were either too big, or were rated for less than 100V (and would surely explode or catch on fire as soon as I turned the record player on).

I figured I would just be able to buy five 20µF’s and then put four in parallel for the 80µF one, but still, finding a 20µF non polarized capacitor rated for 400V or more is quite a challenge. I even set the minimum voltage rating at 200VAC (since the record player is only powered by 120V - I’m American) but that still turned up nothing useful.

Does anyone know where I can buy 20µF non-polarized capacitors rated for at least 200VAC?

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There are lots of motor start capacitors with similar ratings, but you have not made clear why you need nonpolarized capacitors. If they are in the amplifier circuit, probably not.

Please post a schematic diagram of the circuit in which the 20 and 80 uF caps are being used. Hand drawn is fine.

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Was about to say the same thing about the motor capacitors.

Check Amazon, they have both 20uF and 80uF. Don’t know for sure if they will work for your application but it’s worth a try.

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I did find 80uF motor capacitors, but they were ENORMOUS and wouldn’t fit in the record player’s case (it’s one of the little portable ones). So that’s why I’m looking for smaller ones.

Also, I haven’t worked the schematic out yet cause I didn’t think I would need it. It’s all point-to-point writing and components are all buried under each other so I will probably have to take the thing completely apart to get the schematic and I’d rather not do that if I don’t have to.

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You probably don’t need a nonpolarized capacitor, but you haven’t provided enough information for anyone to be sure.

It should go without saying that a polarized capacitor must be installed in the correct orientation.

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