Hi all, Finbar EI0CF measured one of our spiral evolutions under several
different weather conditions. Finbar's site is right on the shore of
Trawbreager Bay so he has sea water close at hand. When we had increased
the top load the ground loss was ultimately reduced to about 20 ohms in
normal (dry) conditions. As one might expect when it was actually raining, a
high loss resistance was measured. (There would have been a water film over
the plastic coated wire used. ) This loss reduced immediately the rain
stopped, but the loss resistance still remained about twice the normal "dry"
value. Even long after the rain has ceased the loss stayed high whilst the
ground was still freshly wet. The measured loss did not return to normal for
about 24 hours afterwards.
I assume fresh rainwater has a high permittivity and also a high resistance.
Over time salts will disolve into the wet mass reducing its resistivity.
These measurements are still in my file as I had not yet decided how to
explain the results. However in view of "corroborating" evidence I will see
if I can pull then together. All measurements were done using a simple RF
bridge described on my web site.
Cheers de Alan G3NYK
[email protected]
http://www.alan.melia.btinternet.co.uk
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