To some extent the term "ground conductivity" is misleading. It gives us
false hope. If we thought of it as ground "resistance" we would gain a
better appreciation of what it does to RF currents. In other words, the
"average ground" is not your friend. It is a very messy resistor (and
capacitor). Current through a resistor generates heat. Heat is loss. One job
of radials is to keep RF currents out of the ground. In other words: you
want the RF currents to flow through the copper not the resistor. (I am
hugely simplifying, but...). Of course, if you do not have any radials, the
ground will help, but the losses will likely to be very high (70 - 90%),
unless you live over a salt-marsh, but even there, copper will be better.
Over salt-water, the situation is different: the water makes a good "ground
plane" (low resistance), but few of us have this advantage.
73 and Take Care!
George,
AA7JV/C6AGU
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