My own experience is that a fence does not degrade the Bev pattern too
much as long as the Bev is sufficiently high above the fence wire. I
mount my wires about 3 m above the fence.
I have never modelled an inductively-loaded Beverage, but my intuition
is that it will not perform any better than an unloaded wire of the same
physical length. The pattern of the Bev is generated by virtue of the
fact that it is excited by different parts of the wave front, the
relative phases of which depend on the direction from which the front
arrives. If the wire itself is too short this desirable decorrelation is
not achieved.
At HF we can inductively load a yagi to make its elements physically
shorter at resonance, but we still need the same spacing between the
elements if we want to duplicate the radiation pattern of the unloaded
yagi. I suspect that the Beverage would behave in a similar fashion.
73, Greg, ZL3IX
On 2019-08-25 05:52 a.m., Mike Waters wrote:
As long as the fence is pointed in the right direction. :-)
www.w0btu.com/Beverage_antennas.html#Misc_Beverage_antenna_notes
On this page, there are some links to ZL3IX (?) experiences with his
Beverages mounted at different heights above metal fences.
73, Mike
www.w0btu.com
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