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[TowerTalk] Re: TopBand: Re: Sloped Beverage Terminations

To: <towertalk@contesting.com>
Subject: [TowerTalk] Re: TopBand: Re: Sloped Beverage Terminations
From: albraun@socket.net (Alan Braun)
Date: Thu, 23 Oct 97 02:59:39
In <19971022150101.AAE17615@fred>, on 10/22/97 
   at 10:50 AM, w8jitom@postoffice.worldnet.att.net said:


>Any wattage, any carbon or metal film will work on 160. The optimum 
>resistance value will be around 300-600 ohms, depending on the wire 
>size, the environment around the antenna, and the ground system 
>resistance. You'll see little difference if you make a termination  error
>on a long antenna, because the long low wire self-terminates  itself from
>the losses along the wire. (If the wire has six dB one  way loss, typical
>for a 500 ft Beverage, the F/B ratio will be at  least 6 dB with NO
>termination at all!)  

>The shorter the wire, and the fussier you are, the more critical it  is
>to get termination correct. Even the wrong termination does not  hurt the
>system too much however, unless you have a lot of noise in  the null
>direction.

I've been following the threads on beverage construction/termination.
Where I live there is only one possible direction to run a beverage,
that being with the termination pointing southwest.  Because of that,
and there not being much DX that direction, I've tried a couple of
times to run beverages about 700' long UNterminated, but have been
very disappointed in the results.  Generally I can't hear much better
with such an antenna than I can with my 1/4 wave sloper (which is my
160 transmit antenna).

Perhaps part of the problem is that these beverages have run within
about 50 feet of my tower, but I wonder if the assembled masses 
could comment on the relative effectiveness of terminated vs un-
terminated beverages?  The books all say that unterminated beverages
differ from terminated ones mainly in that they are bidirectional,
but I wonder if that is too simplistic and that there may be other
factors at work?  Advice, please!

73 - Alan NS0B

* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
* Alan Braun MD, NS0B/V31EV *Internet: albraun@socket.net         *
* Jefferson City, MO        *Packet: NS0B@N0LBA.#cemo.mo.usa.noam *
* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *


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