Run it through the trees, it will work just fine. Use the slope to your
advantage, it will tilt the response angle down. a one wavelength beverage
is a moderately high angle antenna, 10-15 degrees of downslope will not be
noticeable. If the slope is more than that, you can use the slope to help
hide from signals from behind you
I would go to the effort to avoid electrical contact with the trees, but,
just insulation will work just fine, no extra measures needed. For a
permanent installation, I would probably use real screw base insulators-
the kind with a ceramic top on a long lag screw. often used for electric
fence wiring on wood fences. Use the lineman's method of attaching the
wire to the insulator, don't run it THROUGH the insulator, that will make
maintenance very difficult. Attach the wire with a lineman's wrap, and
that will allow enough movement that it will tolerate some motion in the
wind
the beverages at VP6DX were forced through dense brush and used the limbs
for support. This worked very well, but would not last years with wind
moving the wire and chafing through insulation. Use a 6-8 meter long
fiberglass collapsible rod used for fishing wires through ceilings and
attics to help you fish the line through the brush, and support it with the
insulators I mentioned
Make some of them longer than 180 meters- that is minimum length for any
performance on 160. you should have some out to 300-400 meters if
possible, don't worry of they change slope in the middle, just try to keep
the wire in a straight line, don't worry about the varying height. remember
that 320 meters is only 2 wavelengths at topband
do as many as you can. There is no such thing as too many receive antennas
on topband
73
Robin, WA6CDR
----- Original Message -----
From: "Michael Zürch" <dg1cmz@freenet.de>
To: <topband@contesting.com>
Sent: Saturday, April 03, 2010 02:28
Subject: Topband: Do beverage antennas work in dense wood?
However except the ridge at 30°, where a road runs parallel, all other
directions are covered with dense wood. The wood is not cleared after
storms up there, so this makes a dense mess of wood all around the QTH.
The good thing is that this keeps away people that could walk into a
beverage or complain about too much wires around.
Now my question is: would a beverage work if it is put in a height of
about 3m along trees and passing through a lot of garbage wood?
How much does it effect its operation if its mounted at different
heights at different plances, e.g. from 2-4m height changing with the
points to fix the beverage.
According to
http://www.bavarian-contest-club.de/projects/beverage/bev_script.pdf a
lenght of about 180m would be ideal for us to have good performance on
80/40 and still usability on 160m. Also we can't make it too long, since
the terrain slopes fast, especially towards to the US.
Second question: how much does it effect the performance of a beverage
when it is mounted on a sloping hill? (I speak of a height difference
over the lenght of the beverage of maybe 20-40m)
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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