Well I just can't stay away from this discussion.
I'm loading a tower as a ground plane on 160. The ant use 4 radials strapped
to the tower at 32 feet elevation, with shunt feed connected at (about) 95
feet thru a couple of capacitors. Using ON4UN's estimator for the effects of
top loading I calculate that the tower, from 32 ft up, is 3/8 wave high on
160.
Some of you may already know that it works like gangbusters on transmit.
Actually it also works fairly well on receive, but noisy. I also have a 160
dipole oriented N-S up 10 feet which close-in sometimes out-hears the
vertical in actual s-units and for distant DX has 10 db or so better S-N.
But on transmit, experience in the pileups this winter has shown it to be
extremely effective comparing with my peers here in the San Diego area.
I used to use the (stainless steel) guy wires until the '96-97 season when I
paralleled them with 3 tuned copper wires. This is no kidding, that lil ole
change was worth several s-units on the meter. Stainless is not good
radials.
I have no idea whether I could gain a percent or 10 with a "real" ground
system. It ain't in the cards. This system works as well as any other
antenna I know of currently in use locally, and as well as many out of the
area.
The ground plane has had a stunning effect on my country count. For
simplicity and station flexibility it sure beats all that buried wire.
73 Art
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