Topband: Best Height Above Ground for a Beverage RX Antenna

[Larry Molitor]

Tim Duffy K3LR <k3lr at 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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