Jeremy-
>From the layout of your property and your description, I make this
suggestion assuming that the tops of the trees will allow you to support
a wire that will clear your house, and that there are no power lines
leading to the building that would be below the antenna.
If this is a warranted assumption, may I suggest a "loop skywire" as
discussed in the ARRL Handbook. It is nothing more than a horizontal
loop fed directly with 50 ohm coax (RG-58 is best due to its light
weight). From the diagram, you could run the wire from tree #3 to #2, to
#1, to #4 and back to #3. You might put the feedpoint close to the
chimney between trees #3 and 4. From the dimensions, I roughly figure
that the distance between tree #1 and #4 is about 100' giving you roughly
enough air to run 245 to 250' of wire. The loop resonance is
"approximated" and I mean roughly, by the formula 1005/F (Mhz),
rearranging this indicates that that amount of wire is resonant around
4.27 Mhz.
Needless to say, you have to run a tuner for multiband use, but the
antenna's radiation efficiency is high. Even at 30 to 35', I think you
will be pleased with the results. I am running one that is 540' long and
about 20 feet high for 160 Meters, and I use it on every band right on up
through 6 Meters. Plenty of people will call it a cloud warmer, and on
the lower bands it is somewhat of a NVIS antenna. But this has its
benefits, on 80 Meters it allows me to cover all of New England west to
Chicago, south to Georgia and east, well, east to the Atlantic Ocean!!
As you get on the higher bands, the angle of radiation gets lower and
your range increases. I have made contacts into Europe and S. Africa on
20 and 15 without any problems.
It is a simple antenna, cheap, and easy to erect (use bungie cords at the
support points for shock absorbers). The higher you can get it, the
better it will work. DO NOT UNDER ANY CIRCUMSTANCES ERECT THIS OR ANY
ANTENNA IN A WAY THAT IT COULD CONTACT POWER LINES IF IT CAME DOWN !!!!!
Your signal isn't worth jeopardizing your life or your home.
If you have any further questions, ask directly or over the reflector.
I'm sure others would enjoy the discourse!
Best of luck and 73,
Paul - KE1FI
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