Elevated radials are finding their way into broadcast sites. Copper
clad steel can be used, they are less prone to damage from copper
thieves, and in some locations, make it easier to continue operating
while some of the site property is let go for other uses (parking
lots, retail, warehouses...). When done right, the field intensity
and antenna efficiencies equal those found with the standard 120
buried radial ground systems. But the key phrase is "when done
right." The radials need to be high, at least 20 feet as one or two
fellows have indicated, at a minimum. 4 horizontal radials are
needed, at 90 degree angles from each other. Usually the ends are
held up with utility poles. Their length is critical and they must be
terminated with plenty of insulation. All the lengths must be equal.
Because these demands are hard for most hams to meet for 160 meters,
it's usually easier and more realistic for the average ham to simply
lay down lots of radials on the ground and let grass grow over them.
Rob
K5UJ
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