Hi Ed,
> station ground rod measures 50 ohms at 20 ft. down measured with a Biddle
> ground resistance meter. The old electrical service entrance ground
> measures 2 ohms and is about a 100 ft. away from the station ground.
Have fun in the contest!
The resistance of any RF ground system measured at low
frequencies or dc is almost completely meaningless, no matter
what correction factors are applied.
Skin depth at dc is infinitely thick, gradually decreasing until at 160
meters it might just be a few feet deep.
When measuring at 60 Hz (as the Handbook suggests) or at dc,
you are measuring entirely different cross sections of earth. Not
only that, low frequency measurements fail to include many other
losses associated with higher (RF) frequencies.
I can't think of any practical way to measure ground loss except by
watching field strength changes at a fixed point(s) on groundwave
as you change *only* the ground system.
73, Tom W8JI
w8ji@contesting.com
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