There is another "negative" aspect to using mesh, chicken wire, welded
fencing, etc., in the ground system of verticals, and that is the losses
these screens incur due to eddy currents created by the closed loops of the
mesh. These eddy currents can be considerable, especially in higher power
systems, and add loss to the overall system.
In vertical ground systems, it is most important to return the currents to
the feedpoint of the vertical element by the most direct path possible,
whereas screens comprised of many closed loops of mesh or chicken wire,
etc., actually would return less current to the feedpoint. I believe
extending a mesh field out to 1/8 wavelength or more would actually produce
poorer results than 30 or so radials of equal radius.
73, Dave, K1FK
Fort Kent, ME
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