----- Original Message -----
From: "Mike Waters" <mikewate@gmail.com>
To: "topband" <topband@contesting.com>
Sent: Wednesday, June 20, 2012 5:24 PM
Subject: Re: Topband: Beverage Antennas & Trees
>I agree with Jim. Beverages don't have to be ideal to work very well
> indeed, thank you. It's the matching transformers (and maybe their
> grounds)
> that are a more important thing to worry about.
Since "work very well" is entirely subjective it means little unless there
is an ideal benchmark to compare against.
Yes, Ive stressed the transformer design and construction to you several
times on here and elsewhere. That and isolated grounds and common mode
rejection will allow digging to a new layer of DX.
>
> You need not worry that trees and bushes will attenuate the signal at HF.
> Lots of people have installed them in deep woods. If you installed two
> identical, separate Beverages pointed in the same direction --one in the
> woods and one in the clear-- I doubt if you would be able to tell any
> difference between the way they work.
How do you know any of the above without fully testing? It only makes good
sense to at least "assume" that a wire touching branches and low brush
during full sap season
that will also be rained on often in many parts of the world will have many
impedance discontinuities that when added up will likely have a negative
effect.
I walk mine several times a year trimming off wandering growths that have
touched the insulated wire of my Beverages, it seems to me to be smart PM.
This year in particular and due to the warm winter I have a jungle type
explosion of growth from bushes, small pine trees, nasty stuff with thorns
and creeper things.
I prefer to keep them far away thank you and its a cost free exercise.
>
> My Beverages run through the woods for a portion of their length, and they
> work fine. Although I don't have any leaves or other foliage actually
> touching my Beverage's bare open-wire line, there are plenty of places
> where the antenna runs past them. And one of them is supported by tree
> trunks for about half of its length.
Since I rebuilt all mine are now 100% in the woods and well removed from
verticals and radials. Local digital, switchers, and other crud noise has
also been reduced but I have no idea what re-radiation has in thepast or is
affecting now.
Carl
KM1H
>
> 73, Mike
> http://www.w0btu.com/Beverage_antennas.html
>
>
> On Wed, Jun 20, 2012 at 2:51 PM, Jim Brown
> <jim@audiosystemsgroup.com>wrote:
>
>> Mine ... through a lot of brush and scrub trees. ... Bottom line --
>> Beverages don't have to be ideal to work.
>>
> _______________________________________________
> UR RST IS ... ... ..9 QSB QSB - hw? BK
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