So put you're receive antenna hat on. We suspect the ground is the
problem. We are located on the shore of Victoria Lake at a resort. The
soil appears to be sandy but with fresh water lake nearby. 200 feet. The
beverage is in the clear away from large metal objects.
Fresh water has poor conductivity. It is like bad dirt, unless salty. Even
with salt water, the antennas would not make noise, and they would hear
something.
With a 510 ohm termination we measure about 235 ohms when looking across
the termination resistor. Using resistor theory essentially we have two
resistances in parallel. The wire , termination transformer, ground rods
and ground are about 500 ohms. Having not measured this at home I'm not
sure if this is too low or too high of resistance.
It is difficult to measure anything that way, because any common ohmmeter
will read the voltage bias of the earth and ground rods. This will throw off
any reading.
Plus even if the terminations were bad, it would not cause what you
describe.
I would look at feedlines and the radio, and the transformer at the
feedpoint. I hope you are using an isolation style of transformer.
We erected a Flag 29x14 feet mounted just above the ground. This is
purported to be ground independent. Our tests last night indicate this
antenna is not hearing very well either.
No antenna near earth is ground independent, although some antenna types do
not use the earth as a connection point. Any antenna we install near earth
will always be earth dependent, even if we have no earth connection.
I doubt that it is the earth, however. The Flag works increasingly better
with higher conductivity earth, while the Beverage works worse. Even if you
had a case where the earth conductivity was too good for a Beverage, a Flag
antenna would actually be better than over poor earth!
The fact an antenna that likes better earth does not work, and one that
likes poorer earth also does not work, re-enforces the idea that it is the
feedline or radio or something other than the antenna.
We are soliciting suggestions. We only have a small amount of wire and
other antenna stuff, no Home Depot or Radio Shack around. Perhaps we can
build a ground independent antenna that does not care what it sits on.
The only antenna that does not care what it sits on is one that is in space
many wavelengths from earth.
:-)
You have a local problem with a local noise generator, or a problem in the
radio or feedline.
73 Tom
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Topband Reflector
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