In article , Don Pearce
wrote:


The type of rectifier doesn't make a great deal of difference, although
full wave probably has the edge on accuracy. Don't put a capacitor after
it, just let the meter do the averaging, then do the sums: power = v
squared / R.

I'd be wary of this unless I knew the details of the meter. I've seen some
that can give odd results when asked to give a dc level in the presence of
much ac. e.g. One I recall seemed to only sample the input at a low rate,
so became confused as the level flutuations 'beat' with its sampling rate.

Slainte,

Jim

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