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Old March 2nd 07, 04:25 PM posted to rec.radio.amateur.antenna
Richard Harrison Richard Harrison is offline
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First recorded activity by RadioBanter: Jul 2006
Posts: 588
Default The power explanation

Cecil, W5DXP wroote:
"What is the dissipation in the generator using a Norton source?"

According to page 76 of Terman`s 1955 opus:
"Alternatively, a load impedance may be matched to a source of power in
such a way as to make the power delivered to the load a maximum (the
available power of the power source). This is accomplished by making the
load impedance the conjugate of the generator impedance as defined by
Thevenin`s theorem."

On page 75 Terman labels a Norton diagram: "Equivalent Arrangement".

Equivalence means the open-circuit voltage and short-circuit current are
the same whichever diagram represents the power source.

The power dissipated in the source under matched conditions depends not
on the diagramatic representation, but upon how much of the internal
resistance of the source behaves as a resistor does, and how much is
"dissipationless resistance". It`s real, but makes no heat. If it were
fictional, final amplifiers would be limited to 50% efficiency. We all
know many R-F amplifiers have discontinuous input power
which allows efficiencies much in excess of 50%.

Best regards, Richard Harrison. KB5WZI