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Old March 1st 07, 05:58 PM posted to rec.radio.amateur.antenna
Jim Kelley Jim Kelley is offline
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First recorded activity by RadioBanter: Jul 2006
Posts: 666
Default tuner - feedline - antenna question ?

Richard Clark wrote:

On Wed, 28 Feb 2007 13:55:47 -0800, Jim Kelley
wrote:


What I meant was, in what way were you able to attribute and apportion
this heat to its various sources? What evidence were you able to
obtain to show reflected energy re-entering the source output? What
component in the system in fact dissipated the reflected energy? How
were you able to determine the exact source and amount of energy at
any given location within the source? Or did you just presume that
you understood the underlying mechanisms?



Hi Jim,

This knowledge arrived by many avenues.


But primarily, it seems, by speculation. I know how to measure heat,
Richard. What I am asking, and what you have thus far been unable to
answer (which is as I suspected), is how is it that you were able to
ascertain that this heat energy was caused by energy that was
reflected from the load rather than having come directly from the
power supply within the source? How is it that this electromagnetic
energy is so easily reflected from a load, but is utterly immune to
reflection when it encounters the output of a source? I think it's
been fairly well established that the output impedance of these things
is far from 50 ohms. Why should reflected energy not be, at least in
some part, re-reflected back toward the load?

Someone who alleges to be so familiar with load lines should be able
to contend with an increase in dissipation against a mismatched load
without having to explain it as 're-absorbed' reflected energy.

Inductive logic leads us to this junction as the principle target of
reflected power (the signal path is symmetric, after all).


Speculation could also lead to that juction.

Experience
has supported this logic.


It could be experience coupled with misattributed fact. Possible?

73, Jim AC6XG