> Tom, I think you're getting the horizontal and vertical polarization
> cases mixed, with maybe also a little too much focus on the 160m case.
> In his book, Dave Leeson observes that ground characteristics have
> relatively little to do with vertical pattern formation from
> horizontally polarized antennas, because "the reflection is from the
> conductive or dielectric discontinuity between the air and the surface
> of the ground(giving effect to skin depth)..." As for smoothness, he
> observes that "for radio waves in the HF band this shows that ground
> nearly always behaves as a perfectly smoth surface, particularly for
> low angles of incidence."
I guess then we can ignore things like buildings (with wiring), the
slope of the grade, utility lines, and other conductive objects and
still accurately predict results within ten feet of effective height
when the antenna is a few wavelengths high?
73, Tom W8JI
W8JI@contesting.com
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