I've had an antenna similar to Rick's up for several years now, and I've been
quite pleased with it. Mine is a 33 foot, center-fed vertical doublet fed with
300 ohm open wire line. The support for my antenna is made from those military
surplus fiberglass sections that plug together. I originally meant to put up a
40 foot antenna like Rick's, but I was swinging my assembled mast up from the
ground with one end pivoting from a post in the ground, and anything longer
than 33 feet would break at one of the joints. I did not wrap my antenna
around the pole but rather hauled it up on a pulley after the pole was in
place. I have the pole guyed at two points, about halfway up and again at the
top. I'm using black "plastic" rope for the guys and to support the antenna.
The reason for the 300 ohm feedline was that I found a giant reel of it put
out for the garbage man one day (along with a BC-348, HQ-170A, and Galaxy V
which I also picked up). My installation allows me to run
the feedline away from the antenna at 90 degrees, up over the roof of my
garage, and then inside the house through a dryer-vent packed with fiber glass
insulation where I tune it with a home-made, parallel-tuned circuit transmatch
(that I also use to tune my 268 foot center-fed Zepp).
My antenna loads nicely on 30 through 10 meters. An EZNEC analysis shows that
it has a very low angle of radiation on all of those bands, but that above 10
meters it starts to develop high angle lobes. I suspect that Rick's 40 footer
may develop those high lobes at a somewhat lower frequency. My antenna doesn't
load well on 80 and 40 meters. But on 30 through 10 it does a nice job of
working DX. I run as much as 600 watts CW out of an SB-200 to it. As an
example, I recently worked AH6HV in Hawaii (from my QTH in New Mexico) on 20
SSB during the Classic Exchange using barefoot B&W 6100 and Heathkit SB 400
transmitters (each running a pair of 6146s). I've also worked Kazu, JA3KNB,
several times during the Classic Exchange on 15 meters with this antenna.
It's not a beam, but it does give me a lot of fun.
73,
Jim Hanlon, W8KGI
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