About,
"Regardless of the diode rectifier used, you have to be careful about
the
value of the resistor used across the filter cap and the input impedance
of the DVM. If the DVM loads the circuit too much, you get less than the
peak voltage and calculate less than the true power value."
Not at all a concern in this case. Here we are talking about a
transmitter working into a 52 ohm dummy load. And a quite low resistance
tube with its plates connected in parallel. The circuit impedance is
many thousands of times lower than that of a VTVM and even a VOM.
Accuracy is maintained to a high degree, depending only upon the rating
of the DC voltmeter. Yes, I'm speaking in practical terms.
73, Roy K6XK
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