John,
You did not mention it but Im guessing your SWr was around 2:1.
I think you will find that a center fed half wave vertical
will have a feedpoint Z on the order of 100 Ohms when the feedpoint
is 1/4 wavelength over ground.
Bob, W5AH
-----Original Message-----
In a message dated 8/29/01 6:40:55 PM Pacific Daylight Time, kk9a@arrl.net
writes:
<<
I tried to use a halfwave vertical with a parasitic reflector on the beach
in Grand Cayman (ZF) two years ago. I fed my vertical in the center
as a vertical dipole. I modeled it with AO, but when I put it up the SWR
was terrible. I changed it to 1/4 wave verticals and they worked great
being only 1 meter from the ocean. I never did figure out why the vertical
dipole didn't work. When I took the vertical down and layed it on a
chair the SWR was good. I later suspected the coax running down side
of the vertical may have been the problem and I wish I tried pulling it out
horizontally from the antenna. I'd like to try it again sometime when I'm
on a Caribbean vacation.
73,
John
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