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Re: Topband: Do beverage antennas work in dense wood?

To: Michael Zürch <dg1cmz@freenet.de>, Top Band Reflector <topband@contesting.com>
Subject: Re: Topband: Do beverage antennas work in dense wood?
From: Jon Zaimes AA1K <jz73@verizon.net>
Date: Sat, 03 Apr 2010 21:46:09 -0400
List-post: <topband@contesting.com">mailto:topband@contesting.com>
On 4/3/2010 05:28 AM, Michael Zürch wrote:
> Hello Topband-fellows,
Hello Michael,

I have many Beverages through my woods -- thick at spots -- and while 
the normal height is about 3 meters, when tree limbs fall on the wire 
the height may vary greatly but the performance seems to be about the 
same (as long as the wire doesn't break). I use many limbs for support 
points, at some spots I will use insulators on the tree if no limb is 
available. Any insulator should be attached to a small piece of treated 
lumber that is then nailed to the tree -- if the insulator is attached 
directly the tree will quickly grow around it in a few years.

The height is not that critical -- the effective height will be the 
average of all the highs and lows.

One trick I have started using is a "weak link" at one end of the wire 
-- preferably at the terminated end. This is a support wire that is a 
couple sizes smaller than the main antenna wire. Typically a short piece 
of no. 18 when the main antenna wire is no. 12 or 14.

This is arranged so that if a tree or limb falls on the main wire, this 
small support wire breaks rather than the main, heavier wire, and the 
main wire will remain connected to the termination (or feed point). This 
avoids a lot of hiking back and forth to make a repair as would be 
needed when the wire breaks somewhere in the middle. With this, the 
offending tree or limb is removed and then one trip is made to the "weak 
link" end and the wire is pulled up to the normal height and the "weak 
link" replaced.

I have also had Beverages over sloping terrain -- with a variation of 30 
meters or more -- and they worked fine.

73/Jon AA1K
www.aa1k.us (aerial photo of my property shows how dense the woods are)


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