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Richard Clark · September 23rd 07, 06:42 PM posted to rec.radio.amateur.antenna

On Sun, 23 Sep 2007 16:41:08 GMT, (Rick) wrote:

Any opinion, if I would see any difference by putting ina
common mode choke there or replacing the transformer?

Hi Rick,

None whatever. Your tests proved your coax was being effectively
choked by the proximity of earth. However, this may change with
weather and you should repeat your tests throughout the year as the
seasons shift. Further, you may gain from the historical data I
provide below.

Another test: simply listen to the coax shield (move its connection
to the antenna input and leave the center conductor open). Make sure
to provide a good ground for your rig (in fact, you should NEVER
ground your rig through a coax if your rig has any other path to
ground). If your coax is grounded at the antenna site, you should
isolate this connection (absolutely nothing connected at the far end).

Sorry for the parentheticals, but ALL grounds should be connected
TOGETHER independently of your feedline. This may mean another 725
feet of wire (not always observed, but it is code). However, having
said this, it does not follow that you will actually observe any
improvement. It could also kill the Beverage action (due to the field
being retarded by the earth which gives rise to a sloping, traveling
wave).

As no one is probably very well instructed on Beverages (which may
include ON4UN because his readers never cite any actual historical
data), you may well do to go to the source:
Harold H. Beverage & Anti-static tuned antennas with Chester W. Rice.
''The Barrage Receiver
Using a 10 mile long wire on the ground, they eliminated static
originating in the Caribbean that masked European signals. The wire
described ran in the opposite direction of their antenna pointing
(just as yours) into central Europe.

These tests were performed nearby you (albeit 80 years ago) by RCA. If
you live in proximity to a good engineering library, I can supply many
inventors' names you would do well to research.

73's
Richard Clark, KB7QHC