> On the other hand, vertically polarized signals are re-enforced by
> the earth. Antennas near earth "want" to hear vertical signals,
> because the earth tends to re-enforce vertically polarized signals
> and cancel horizontally polarized signals.
>
> Actually, this is also the very reason ground wave propagation
> must be vertically polarized, and why the noise that propagates
> along the earth for a distance is all vertically polarized.
I overheard a ham on 75 fone allow as the reason his signal
was not very strong was because of ground wave attenuation.
We could use a few words on the relationship (for more or
less local (i.e. up to perhaps 50/75 miles or so) of signal strengths
for NVIS horizontal antennas, vertical antennas, and ground wave
propagation--at 75 meters.
thanks
k7puc
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