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Re: integrating true RMS wattmeter



Original poster: dest <dest@xxxxxxxxxxxxx>

Hallo.

this wattmeter has an awfully long display stabilization time - about 4
sec! that`s real suxxx, so i just decreased C from 2.2uF to 0.47uF,
and added first order low-pass filter to the oa output - just RC ckt.
R=10KOhm, C=3.3uF, so now you can get very smooth readings 4 times
faster with no impact on accuracy and at no cost : )
p.s.
you must use DVM with Rinput~10MOhm as display, if your DVM has
Rinput~1MOhm, then better use R=1KOhm, C=33uF.

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I don't doubt that my logic is flawed, could somebody tell me where?
08-08-97 (c) Gary Lau