Message: 7
Date: Tue, 27 Oct 2009 11:26:44 +0100
From: HA0DU Steve <ha0du@dx.hu>
Subject: Topband: Beverages through the forest
To: topband@contesting.com
Message-ID: <4AE6CAE4.4000708@dx.hu>
Content-Type: text/plain; charset=ISO-8859-2; format=flowed
Dear All,
When 12 years ago we moved to a one-hectar farm in the middle of a
20,000 hectar forest, I had doubts if I can make antennas tall enough to
"be heard". I also saw that the maximum wire length within my property
was about 140 meters in the diagonal. I needed something longer, so I
looked around...
Our only neighbor was the forester, who told me I can hang up wires
anywhere, any length, provided nobody gets strangled. So I used the
unlimited space to install 11 identical Beverages, each 176 meters long.
I made some comparison tests and found that over sandy terrain the
optimum height was 10 to 12 feet. I am also using #12 AWG stranded
insulated wire.
Over the years maintaining 11 wires became unnecessary, so today I only
have 3 (NW, NE and S), but each of them are 1,600 feet long. (For TX5C I
had to extend the NW Bev to 2,400 feet). I also changed the hanging
method. Originally I attached the wire to the trees by thin nylon ropes
(bailer rope), so the wires were really zig-zagging. Instead now I put
pieces of bailer rope between pairs of old trees along the path, and the
Bev wire is attached to these, which results in less zig-zagging and
larger distances from trees. The ropes are a little loose, so even if
these old trees are moving in the wind, the ropes are not broken. I may
be wrong but I thought perhaps when the wire is very close to a live
tree it forms some kind of a capacitor and I did not like it. With the
new method I have about 40-50 suspension points at each of the Bevs, and
maintenance is easy, using a small stepladder and a reel of bailing rope
in a backpack.
Although I have a preamplifier, I do not use it very often, it is just
not necessary in such a low noise environment. There is no other house
with electricity in a 1 km radius and our electricity supply is a ground
cable. In fact when there is something very important, I even turn
refrigerators and all other household electrical equipment temporarily
off, so that I minimize the man-made noise. For the eleven Beverages I
also used to have a selector switch, but now I just connect the right
antenna coax to the RX ant input of my receiver.
If it works? Yes indeed, I tried all kinds of small receiving antennas
including pennants, flags, magnetic loops, slinkies, mostly everything I
found in the literature, but the Beverage outperformed all of them. Very
soon you can listen to some of the recordings I made on 160 meters at
http://ha0du.com
Best 73
Steve HA0DU
------------------------------
Like Steve, I live in a very rural area of NH and have a rather large
woodlot where antennas can be installed.
Simply stated, his suggestions are a good template on how to install
Beverages. In the past, I had five Beverages but really only used two, NE
and NW. I am now using two KD9SV bi-directional antennas NE-SW and NW-SE. I
run the antennas from tree to tree and use Steve's idea for using supports
between trees to keep the antenna from zigging and zagging. My land is a
combination of flat and sloping up to the NE and I run my antennas at 8-10'
above ground (rocky clay) to keep snowmobiles, hunters, deer and moose from
taking them down. Ice storms are another matter as I lost all wire antennas
last December. Hopefully I can get my two back up before winter REALLY sets.
I also agree with him that after trying a myriad of other antennas, nothing
beats the Beverage. I did install a pennant but have been underwhelmed with
its performance. That said, another op in MA has phased pennants and he
reports they work well for him.
The key is having enough land to install them. I'd favor a short Beverage,
200', over a pennant.
And as a twofer, I'd rather not see RTTY contesting on 160. That said, we
will never reconcile the desires of contesters versus DX'ers.
73 Craig
Craig Clark K1QX
Radioware
PO Box 209
Rindge NH 03461
603 899 6957
NOTE NEW EMAIL ADDRESS JCCLARK@RADIUSNORTH.NET
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