(...)
5) Longer Bev's (over 600 feet) are worthless if laid on the ground.
I have all my 5 beverages laid on the ground, 2 of them are between
180-200m (600 feet) long and in my case those 2 beverages are my best RX
antennas on 160 and 80m, but almost useless on 40m (they're a bit deaf...).
I work mostly on 80m and their performence on this band is OK, last sunday
the longest one (200m) helped me to hear (and work) NL7Z which is not so
easy from this part of EU.
On the other hand, I never had oportunity to compare them with a wire 6 or 8
feet above the ground, but have to admit that often I find people with the
same lenght beverages, but a above the ground (not BOGs) and are hearing
better than me..
73's
Mac SP2XF
----- Original Message -----
From: "Larry Molitor" <w7iuv@yahoo.com>
To: <k3lr@k3lr.com>; <Topband@contesting.com>
Sent: Wednesday, January 10, 2007 6:29 PM
Subject: Re: Topband: Best Height Above Ground for a Beverage RX Antenna
>
>
> Tim Duffy K3LR <k3lr@k3lr.com> wrote:I am curious if there are directional
> improvements to be gained with Beverage antennas with respect to height
> above ground? What changes at 6 ft, 8 ft or 10 ft? How important is it to
> have the height consistent over the entire length of the Beverage?
>
> ....
>
>
> Over the 35 years or so I have been building and using Beverages, I've
> paid attention to what works and what does not work. The following
> observations are consistent and reproducible over many years and several
> different locations:
>
> 1) Lower is better (generally speaking)
> 2) Short Bev's (under 300 feet) are worthless if made 10 feet high.
> 3) Short Bev's (under 300 feet) out perform computer predictions if laid
> on the ground or at least not more than 30 inches above it.
> 4) The closer to the dirt, the less interaction there is with surrounding
> structures.
> 5) Longer Bev's (over 600 feet) are worthless if laid on the ground.
> 6) There is some evidence (but not conclusive) that very long Bev's work
> better if higher, say 10 feet or a little more. If I have the opportunity,
> I would like to look at this again.
> 7) Raising and lowering the wire height (for instance over a driveway) of
> moderate to long length Bev's does not seem to adversely affect
> performance.
> 8) I have some results that indicate it is better to follow the terrain
> than to suspend over low areas like dry washes and gulleys. I have not
> been able to verify this observation in enough different locations to be
> certain it is always true.
> 9) Every Bev I've installed with height above ground of between 24 and 36
> inches and lengths between 200 feet and 1200 feet has met or exceeded
> performance expectations. Wires installed at heights between 8 feet and 10
> feet above ground consistently disappoint me.
>
> I offer no theories about the above observations. I only care what works
> in practice and what doesn't. Local conditions and availability of
> materials have more of an effect on the results than do all the computer
> simulations in the world. You pays your nickel and you takes your chances!
>
> 73,
>
> Larry - W7IUV
> DN07dg - central WA
> http://w7iuv.com
>
>
>
>
>
>
>
>
>
> ---------------------------------
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