[TowerTalk] halfwave verticals -Elevated

Bob Alexander realex@flash.net
Thu, 30 Aug 2001 20:28:54 -0500


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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