[TowerTalk] mismatch loss and SWR

[Robert Hummel]

>2. Depending on the severity of the mismatch, a tuned output circuit (like
>those found in amateur antenna tuners, tube-based power amplifiers and the
>older tube-based transmitters) can be used to create a conjugate match that
>presents a 50-ohm impedance when looking from the transmitter to the
>transmission line while at the same time presenting a high impedance when
>looking from the transmission line to the transmitter. The result is maximum
>power transfer from the transmitter to the transmisstion line and
>re-reflection of any reflected power back to the antenna.

It seems intuitively that if this were true, you'd never hear anything when
you switch to RCV. Recipricocity must apply in both directions. It's been a
while since I designed a tube rig, but I'm pretty sure it was the impedance
of the transmitter PA circuit, not the tuning network that presented the
non-reciprical impedance (since it's an active circuit).


 *=======================*
* Robert L. Hummel                       	 *
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* email:    rhummel@cheshire.net	 *
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*              Sullivan, NH 03445		 *
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