[Amps] RF Grounding

[Joe Isabella]

Two things...
 
In 1921 they were using VLF, and as we now know, VLF antennas do work well through the earth (and oceans).
 
Your antenna laying down near the ground turned into a NVIS (Near Vertical Incidence Skywave) antenna.  If you were to compare reports with a few stations varying in distance from you, the closer stations would hear you the best, and your signal would drop as distance increased.  With it up high, you probably had a much better signal further out.  It pretty much depends on conditions, though.  Sometimes, the NVIS antennas don't do so well (we use them in the military), other times, they out-perform dipoles.
 
Joe, N3JI


Bruce Lanning <blanning at acadia.net> wrote:
I have been following all the talk regarding RF grounds and the most recent 
tale of using water well casings as RF radiators.
All this reminded me of an article I read as a kid in an old Amateur Radio 
Handbook ( I think it was 1921) there was an illustration of an in the 
ground antenna. This fellow had a hole in the ground, about six feet deep 
and six feet in diameter. In this hole he had a large spiral of copper 
tubing supported in the bottom of the hole in a mason jar, with the other 
end connected to his transmitter. I always wanted to try this out, but as I 
am now 75 years old, I guess it will have to wait to the next life.

Another interesting phenomenon. Also many years ago on 75 meters, I used to 
talk to the locals in the Norfolk, VA area. One evening the boys said that 
my signal was greatly improved. I went outside and my 136 foot dipole was on 
the ground. The end insulator had broken. It stayed in this position for 
many months and worked great.
Bruce W1GBS ex W4SKT.


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