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Old 05-17-2012, 08:02 PM
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Magnavox300 Magnavox300 is offline
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Quote:
Originally Posted by N2IXK View Post
In most cases, doubling the capacitance will not cause any problems. Possible exceptions:

Filter caps right off the cathode of a rectifier tube. Using a grossly oversize cap here can overtax the rectifier tube due to excessive charging current. Tube manuals usually specify a maximum capacitance value for each tube type and filter arrangement.

Caps used in timing circuits.

Capacitors used in loudspeaker crossover networks.

Electrolytic capacitors in general have pretty lousy tolerance specs. -20%/+100% was typical for tube era caps

Exact tube era values can be a bit hard to find these days. instead of 20, 30, 50 uF, today 22, 33, 47 are the usual nominal values.
So I can use a 47 instead of a 50 uf electrolytic? I thought I should stay at least the same, or go higher?
Or is that the 20% rule, if so how do I calculate that, just so I will know in the future.
Thanks...

Magnavox300
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