16 Nov
2004
16 Nov
'04
10:19 a.m.
The AC setting on a voltmeter will let you know if you
have too much ripp=
le=20
on a DC supply.
That depends very much on the voltmeter!. Most of the ones I have here
simply use a rectifier on the AC ranges so that the meter responds to
either the peak or the mean of the absolute value of the input signal,
with a suitable scalling correciton so the actual reading is the RMS
value assuming a sine wave input.
They will quite happily indicate (and mis-read the value of, of course) a
DC input when set to AC,.
-tony