On 7/9/2020 9:07 AM, jimlux wrote:
Then, there's the "power absorbed in the soil" issue - an elevated
vertical dipole, or a limited number of above ground horizontal radials
both have the potential problem that the near field of the antenna is
"in the soil" and absorbing power. Highly conductive or highly wet soil
both have a good (high) reflection coefficient, so less of the field
winds up being absorbed.
I have heard this kind of theory before. But I did A/B testing of a 1/4
wave ground mounted vertical with 32 1/4 wave radials vs a 1/2
wave ground mounted vertical (driven from the bottom) with no
radials or counterpoise (except the coax shield running away.
This was on 20 meters. As far as I could determine from listening
to signals on the air, the antennas were equal, over my high
conductivity ground. The drive impedance of the 1/2 wave
was around 900 ohms; a base mounting matching network
was employed.
73
Rick N6RK
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