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Old November 5th 07, 03:07 PM posted to rec.radio.amateur.antenna
Cecil Moore[_2_] Cecil Moore[_2_] is offline
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First recorded activity by RadioBanter: Mar 2007
Posts: 3,521
Default question about wire antenna and tuner

Highland Ham wrote:
Roy Lewallen wrote:
But I did write up a lengthy essay several years ago, in response to
the same insistent rantings about reflecting waves of average power
that's still going on in this newsgroup, and it has some numerical
examples with a very simple circuit which illustrate the problems with
what you said. You can get it at
http://eznec.com/misc/Food_for_thought.pdf.

===========================
Roy ,Tnx vy much for that ,much appreciated. ( it now sits in my
'Antenna' file)


Unfortunately, all it proves is that reflected power
doesn't always cause heating of the source. It does
not prove that reflected power never causes heating
of the source but that seems to be what w7el would
have us believe that he has proven.

If constructive interference between reflected waves
is in the direction of the load, the source will run
cool and the load will run hot. An antenna tuner can
accomplish that configuration.

If constructive interference energy flows unimpeded
backwards into the source without being re-reflected,
the source will run hot and the load will run cool.

This is no-brainer conservation of energy stuff.
Simply calculate the total number of joules contained
in the closed system and observe where those joules go.
Hint: the total number of joules contained in the
system are *exactly* the number of joules needed to
support the joules/sec in the forward and reflected
power readings.
--
73, Cecil http://www.w5dxp.com