Mauri I4JMY Said:
Such fact leads to the requirement of a much better and bigger ground
plane (much more and longer radials) than it is needed to maximize
efficiency in the case of a quarter wave vertical.
Thomas KN4LF Says:
Unfortunately, for a 1/2 wave vertical the Fresnel Zone where the first
reflection occurs and your low angle pattern develops and a high quality
ground screen would need to be concentrated, is approx. 50,800 feet (10
miles) away from the antenna. In my case for my QTH, 10 miles in every
direction is either swamp or the ocean.
http://kn4lf.tripod.com/index-6.html
I use four 1/4 wave counterpoise wires 15 feet off of a ground surface
that contains a high water table.
Thomas Giella
KN4LF
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