In a message dated 11/15/01 1:36:07 PM Pacific Standard Time,
dsthill@cbcbarbados.bb writes:<<
Dear T-Ters,
During the recent CQ WW Phone contest, we tried an interesting antenna array
at 8P4B for 80 and 40m. Essentially, two HF2V verticals were erected with
about a 33ft seperation roughly north-south.
The first unit was fed with RG8, the second was tuned to the same freq. as
the first, and a length of about 30ft of RG58 was connected at the
feedpoint. The first antenna was therefore driven, the second was hoped or
assumed to be a parasitic reflector based on the unterminated cable at its
feedpoint.
My question to the reflector is does this array make any sense to anyone and
is it a model that can be worked on and enhanced in any way?? Or should we
now explore simply feeding both antennas as described in the antenna book
with the appropiate 1/4 wave lines and 3/4 wave lines feeding to a coaxial
tee then to the transmitter??
Bottom line. What's the best way to use two HF2V antennas in such a way as
to maximise their utility on 80 and 40m?
Also... Has anyone built an 80m 4-square antenna using the HF2V - any
potential problems I should be looking for???
Thanks guys.
Dean St. Hill - 8P6SH
vision2000@sunbeach.net
dsthill@cbcbarbados.bb
>>
Dean I'm not sure what the HF2V is but raise the base of your verticals off
the ground as high as possible. Try something different. As you do that the
radials have to slope down and far fewer of them are needed. They can be
used for guys. It starts to approach the performance of a 1/2 wave and all
kinds of good thing happen. It's somewhat similar to a Discone and I've
never read any discussion of the E Field losses around the Discone radial
base although I'm sure there are some. Be prepared for some surprises.
I only know of one other person mounting a 1/4 wave 40M vertical on top of a
100' tower with say 8 radials sloping down at 60 degrees? None of all that
"Radial Heavy Math" needed either. It's a best kept performance secret.
K7GCO
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Trylon Titan towers, coax, hardline and more. Also check out our self
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