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Old June 13th 10, 09:36 PM posted to rec.radio.amateur.antenna
Richard Fry Richard Fry is offline
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First recorded activity by RadioBanter: Jun 2006
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Default "Non-dissipative Source Resistance"

On Jun 13, 2:31*pm, Richard Clark wrote:


Medenhall's paper shows "RF spectrum showing distortion products"
that are 30dB down.


Not near the resonant frequency of the output tuning/matching network.

He shows as little as 5 dB at 0.8 MHz offset of the external signal
from the carrier of that tx. It would be less than 5 dB for lesser
separations.

The reason that the IM performance improves for greater frequency
separations is related to the r-f bandwidth of the output network --
not the "linear" operating characteristics of the PA, or that a 50+j0
ohm load is seen by the external energy reaching the tx output
connector.

RF