Yacht Rf ground and radials
An arithmetical correction. I forgot to divide by Pi.
The resistance of a hemispherical electrode, 9 inches diameter, in
salt sea water, is even smaller. It is only 0.32 ohms.
Incidentally. the resistance of a flat circular disk of diameter D
metres, in contact with the soil surface, is given by :
R = S / 2 / D ohms,
where S = soil resistivity in ohm-metres.
In sea water, a disk of 12 inches diameter has a resistance of 0.37
ohms. Which is negligible in comparison with the radiation resistance
of a 1/4-wave vertical antenna of 36 ohms.
Careful readers should make a note of these hints and tips, free to
USA citizens, in their notebooks.
My own notebooks extend from volumes A to letter S. I'm wondering who
to leave them to in my Will & Last Testament.
----
Reg, G4FGQ.
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