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Old May 6th 04, 02:24 PM
Gene Fuller
 
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Richard,

I am well aware of the properties of the phase reversal, cancellation of
direct and reflected waves, and so on. I have no substantive
disagreements with Terman.

I suspect Richard Clark was exercising a bit of poetic license by
stating that the horizontal polarization was "shorted" at the conducting
ground plane, perhaps in a vain attempt to simplify his explanation to
the original poster.

However, this statement is simply wrong. If it were true there would be
no NVIS nor any reflections at all from a normal incidence wave on a
conducting surface. Radar would not work. Mirrors would not work.

Wave cancellation is not such a difficult topic (except on RRAA). There
is no need to invoke phony arguments about waves "shorting".

73,
Gene
W4SZ

Richard Harrison wrote:
Gene, W4SZ wrote:
"---I was commenting on your assertion that the horizontal polarization
is "shorted out" at a conductive surfacce."

Richard Clark`s description may be indelicate but as I recall, Terman
says rouighly the same in several instances. Wish I had a copy at hand.
Terman says that a horizontally polarized low-angle wave suffers a phase
reversal upon reflection and as the difference in path length is
negligible between incident and reflected waves at low angles, the waves
being of opposite phase add to zero.

Best regards, Richard Harrison, KB5WZI