----- Original Message -----
From: <Cqtestk4xs@aol.com>
To: <topband@contesting.com>
Sent: Saturday, August 05, 2006 7:57 AM
Subject: Re: Topband: elevated radials
>I am not an expert on radials but a very nice piece appeared on elevated
>guys appeared in the NCJ about a year ago. The gist of the article was
>four elevated radials >over average ground at 65 feet played just about the
>same as a 60 radial buried system. I don't have the particulars and my
>NCJs are packed away for moving, but it >was part of a three part series
>that made interesting reading.
>
> I actually built it as a suspended wire vertical with the base at 65 feet
> and it played well. However, I was deaf as a stone since I have extremely
> high line noise on >160 so I never was able to give it a fair evaluation.
>
> Bill K4XS
All,
I constructed my first 160 Meter Ground Plane here in late 1995. Insulated
base 1/8 WL AGL and a full 1/4 WL above that. From the base, extending
outward and slightly downward to the top of 55 foot tall wooden poles at the
quadrants, I installed four, 1/4 WL long, caged radials consisting of 4 # 12
copperweld wires each spaced in a 1 foot square.
The element is series fed and the feedpoint impedance is textbook. The
performance for the past ten years has been superb.
I somewhat duplicated this antenna scheme at XZ0A in 2000 and at the W7MCO
QTH. I also have done preliminary testing the past two winters with a gamma
matched version utilizing the upper portion of a 200' grounded
communications tower on the top of a 6,500' mountain. In all four cases,
the results have been outstanding. I have also constructed a wire cage
vertical and suspended it from a catenary cable attaced to the top of a 250'
tower such that the base was a bit more than 1/8 WL AGL. All of these
antennas have been used in 160 Meter contests, where direct competition
shows the true capability of the radiator.
The common component of five antennas is the elevated radials. NOT elevated
10-15', or gull winged from the base, but truly elevated Ground Plane
antennas. Just imagine one of the little 2 Meter, 1/4 WL Ground Planes with
it's 19' spike and 4 sloping radials. Magnify that antenna 80 times and
place the base significantly AGL and you have a superb transmitting antenna
for 160 Meters.
In these five locations the surrounding objects and terrain (and the
temporary time element at XZ0A and the 250' tower) have dictated doing
something other than traditional multiple, on the ground radials. It has
been much easier to do the elevated radials. The results ARE everything!!!!
I highly recommend the elevated radial systems when done in this manner.
73, and good luck with your projects.
Milt, N5IA
DM52, in SW New Mexico
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