Maybe you had the wrong expectations. Beverages (with a capital B) are very
inefficient antennas so the signals you receive will always be much weaker
on the Beverage than on a typical transmit dipole or vertical. The
advantage of the Beverage is that they are horizontally polarized and fairly
directional. This helps them reject vertically polarized local noise
sources and also noise from off the sides. So while the desired signal is
much weaker the undesired noise is usually much, much weaker which improves
the snr. Also, you must test over some period of time in various
conditions. There are times when the Beverage won't seem to be working at
all because of factors like having the noise coming from the same direction
and distance as the desired signals. Also I think arrival angle affects
their performance, as well as conditions that favor vertical polarization
over horizontal. You will also see more improvement if you use one of the
systems that makes them unidirectional instead of bidirectional, since that
reduces the noise pickup by another 3db while keeping the desired signal
intact... that change alone can be much greater than 3db in some areas, like
in New England with a Beverage toward Europe, if its bidirectional it is
also picking up thunderstorm noise and qrm from the states off the back,
make it unidirectional and most of that goes away and you just hear Europe.
David Robbins K1TTT
e-mail: mailto:k1ttt@arrl.net
web: http://www.k1ttt.net
AR-Cluster node: 145.69MHz or telnet://dxc.k1ttt.net
> -----Original Message-----
> From: towertalk-bounces@contesting.com [mailto:towertalk-
> bounces@contesting.com] On Behalf Of wa3afs@inav.net
> Sent: Saturday, January 06, 2007 03:37
> To: towertalk@contesting.com
> Subject: [TowerTalk] Short Beverage??
>
> I am new to the beverage world...
>
> I built and installed a 540 foot beverage (about 7 feet above ground in a
> more or less straight path among the trees.
> I am not pointing at True North!). Results were less than spectacular.
> Maybe my expectations were too high. (I am
> only comparing with signals coming from the general direction that the
> beverage is pointing).
>
> I find that my pair of phased coaxial inverted Ls hear better or at the
> best the same as the beverage.
>
> A couple of questions...
>
> 1. Is 540 feet too short? With a little difficulty I could scrape out
> another 100 feet (but the beverage feed line would
> be another 100 feet longer). Would that be any benefit for 160M? Going
> beyond 640 feet would likely put the
> beverage very close to the power lines which I want to avoid.
>
> 2. Do I need an outboard pre-amp? My ICOM 756 PRO II has built-in pre-
> amps.
>
> I will be looking at the DX engineering dual direction beverage system and
> want to know if I should be content with
> using 500 feet of ladder line or is it worth getting the extra and going
> to 600 to 650 feet? Any experience with
> beverages of similar lengths would be appreciated.
>
> Thanks and 73
> Bruce
>
>
> _______________________________________________
>
>
>
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