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Old October 6th 03, 08:20 PM
Richard Harrison
 
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Tam, WB2TT wrote:
"--I wonder if the meter can be mislead by a reactive source impedance
that forces the current to be out of phase with the voltage."

In the usual h-f transmission line, Zo appears as an Ro. This means that
you put volts across it and the resulting current in the line travels
according to Ohm`s law controlled by the surge impedance of the line. Ro
means the current is in-phase with the volts across the line in both
directions of travel. The funny stuff seen on a line with reflections
comes from looking at both directions of travel at the same time. That`s
not the best way to look at the line and that`s why the Bird wattmeter
uses a directional coupler to extract information on the traveling wave
in one direction at a time.

Surely maximum power transfer is enabled by a conjugate match. "Dumb
bunny " SWR meters may indicate anything.

Terman says on page 76 of his 1955 edition regarding maximum power
transfer:
"This is accomplished by making the load the conjugate of its generator
impedance as defined by thevenin`s theorem."

It is Walt who is "bullet-proof" on this.

Best regards, Richard Harrison, KB5WZI