Charles,
I have two reversible beverages running through the woods. They both
follow the terrain and are about 5-6 feet off the ground on average. One
of them is about 500' and runs towards JA down the side of a wooded hill
through some marsh areas and terminates in woods and the other is 585'
and runs about one third over a pond, one third over flat land and one
third in heavy woods running uphill towards Europe. We have lots of deer
everywhere but no problems with them and the antennas.
Both beverages work well as far as I can tell and the original one,
towards Europe, astounded me when I first tried it as a single wire. I
could hear signals well that were in the noise on the inverted L. Both
beverages have allowed me to hear and work stations that I would never
have even heard without them.
One of this summer's projects is a third two wire beverage, through the
woods, to the mid Pacific and I expect the same results.
My inverted L is hung from a tree with about 35-40 insulated radials on
the ground. A few of them are around 140' but many of the later radials
are about 60'. Most of the return current in the radial field is close
to the antenna and radials on the ground are not resonant so you might
consider cutting some of your in the woods radials in half and doubling
the number of shorter radials which might help.
I am located between Kingston and New Paltz, NY on the side of a hill
over really poor ground but I now have 160M DXCC starting from only a
few years ago.
Les W2LK
-------- Original Message --------
Subject: Topband: Forestry Effect on Antennas and Radials
From: Charles Moizeau <w2sh@msn.com>
Date: Sat, July 03, 2010 6:11 pm
To: Topband <topband@contesting.com>
At my QTH in NJ I have the capability to mount a 500-foot,
two-line, reversible Beverage running NE-SW.
However, I am hesitant to undertake this project because the antenna
would be entirely in the woods. These are not dense woods, for deer now
consume every sapling. Therefore, there are only trees of from 25
to 90 feet high.
Because of the deer, the Beverage would have to be at least
six feet high.
Two questions:
1) Would the antenna, 500 feet
long, still be reasonably effective at that height? 2) Would it be able
to
receive an adequate signal in the described woods?
For the record, I already notice that 16 in-ground radials,
each 160 feet long and running entirely in the woods, produced very
little
change in the performance of my vertical transmitting antenna when they
were
added to an existing field of 22 radials, 60-120 feet long, installed in
an
open lawn area.
I have tentatively concluded that the woods to the north are
absorbing the radiation from my transmit antenna, and therefore the same
kind
of woods, lying to the south and east but more than 100 feet away, will
seriously diminish the signal reaching the Beverage.
I’d greatly welcome reading comments on this list about your
experiences with the effects of wooded terrain on Beverages and also on
in-ground radials.
73,
Charles,W2SH
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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