I assume that you need NEC4 to accurately model a vertical and elevated
radials. The original poster was using a program called Antenna Model which
I never heard of.
John KK9A
Jim Lux wrote:
It's probably more that the soil dielectric properties far from the
antenna have a significant effect on vertical polarized propagation,
while for horizontal polarization, the soil is basically a mirror,
regardless of the dielectric properties. This is one reason that HFTA is
for H-pol antennas - it's easier to compute.
The modeling tool will tell you the amplitude of the "launched wave" and
will factor in the loss in the soil directly under the antenna, which is
greatly reduced by radials. But it *might not* factor in the effect of
the soil hundreds of meters away, or, the soil there might have
different dielectric properties than the soil you used in your model.
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