I sure have been learning a lot here lately, thanks to several
contributors.
What has become obvious is that I cannot compete in terms of efficiency
and low angles with guys like K0HA and his wonderful 44mS/m soil
conductivity or K1ZM and his radials in the ocean. Their lowest angles
are below 2 degrees.
My soil consists of solid rock that ranges from exposed to about 2'
below the surface. That would put me in the 1mS/m category or less which
also pretty much agrees with the soil map in the ARRL Antenna Manual.
That is known as Very Poor Soil.
>From reading the Brewster Angle graph in that manual I will have very
little radiation below about 15 degrees no matter how many radials I
use..on or 20' above ground.
So what remains to contend with is improving efficiency in the 15-45
degree range.
Will adding more radials be the answer?
How many?
Any idea how many dB improvement over the existing 6 radials?
Will measuring FS off the end of one direction give a meaningful
indication of what is happening in the far field at higher elevations?
Does the slope of my hill improve anything? My elevation drops 400' in
about 1 mile over similar poor soil. It then flattens out for several
miles over an area with considerable wetlands, high water tables, many
streams, etc.
And finally: does anyone here have access to NEC-4 and would be willing
to model my antenna and terrain?
Tnx Carl KM1H
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