Richard,
What you said is largely accurate, however at low S/N ratios, or where the
distortion becomes comparable to the signal level, the reading of the
composite signal (signal+noise+distortion) with anything other than an RMS
meter could produce erroneous results.
Joe
W3JDR
"Richard Clark" wrote in message
...
On Fri, 14 Oct 2005 13:08:22 -0500, "Steve Nosko"
wrote:
A meter, a pure 1kHz tone modulated signal generator and a 1kHz notch is
all
that is needed. What happens if you don't have a "real" RMS meter? I
don't
know.
Hi Steve,
You don't need a "real" RMS meter. The expressed requirement for a
pure 1kHz tone provides the necessary sine wave shape such that it
simply becomes a matter of scale calibration. If you had said a
square wave 1KHz tone (nothing pure about that), then you would have
to dig deep for a "real" RMS meter. That too, could be scaled, but I
wouldn't count on it because it would be a rare amplifier chain that
could faithfully keep it square - and the notch would inject it into
the measurement as distortion and noise.
73's
Richard Clark, KB7QHC
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