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Old June 16th 08, 05:59 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 Efficiency and maximum power transfer

Owen Duffy wrote:
"... but asserting that things are linear because there are no harmonics
is wrong and being so, is no support for your atgument."

No one is arguing that an amplitude modulated wave can be amplified by a
Class C amplifier stage unimpaired by amplitude distortion.

Terman wrote on page 525 0f his 1955 opus:
"Amplitude distortion exists when the modulation envelope contains
frequency components not present in the modulating signal. Thus if the
modulating signal is a sine wave, then amplitude distortion will cause
the envelope to contain harmonics of the modulating signal, which in
turn denotes the presence of high-order sideband components that differ
from the carrier frequency by harmonics of the modulating frequency."

I`ve used microwave system performance monitors which alarmed on this
principle.

If there are no harmonics there is no distortion no matter how lousy the
transfer function. It is legal to filter out noise and distortion.

Best regards, Richard Harrison, KB5WZI