Great sharing of thoughts, ideas, and even reality on this topic!
As to some real world measurements, search ZL3IX on this link
and review his experiences with Beverages above a fence ...
http://www.w0btu.com/Beverage_antennas.html#Beverage_On_the_Ground
That will show you some documentation to review for more details.
Note his first data results, and then after he made changes there.
As another data point, I tried two Beverages, one running East, the
other running West, from a common feedpoint, in other words they did
not overlap or run parallel, spaced 2-3' up above my wire fence for
several hundred feet in each direction. My actual results were NOT
favorable as, lack of much F/B, pattern, and seemed to be noisy.
That is very much in-line with the first test results of ZL3IX. I
have considered repeating the same, but much higher above the fence
as an alternative idea if other possibilities do not pan out here.
Jim Brown, model your Beverages on 160m, note the beam width of the
lobes, then do it again on 40m, unless you have a found a magic
antenna, the beam width will be much narrower on 40m as compared to
160m. In your case it appears your headings are 'spot on' but the
reality is the lobes do and will narrow as the frequency goes up.
Real world experience here, and confirmed via modeling, was that a
1200'Beverage at 10 degrees was simply too narrow for 40m on the
more common headings. Over the pole, certainly it worked very well,
but not for the more common Europe headings from here in middle Tenn.
Hope this helps and see you in the pileups!
73 de Billy, AA4NU
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