Spehro Pefhany wrote:

> ...Ripple p-p =  I/(C * 120)  (for full-wave and 60Hz)
> Eg. 1A, you need 1V of ripple, C = I*1V/120 = *1/120)F = 8,300uF.

I think you got this wrong, should be:
     C =  I/(V*120)
so smaller ripple requires bigger cap, but the answer is the same
because V = 1V!

> Why do you need 1A? That's an awful lot. At 100mA you might be able to
> use a cheap and small 1000uF part.

C = I/(V*120) = 0.1/120 = 830 uF

Cheers,
David

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