Forgive me, please, if I'm re-hashing a bit of the "...same-old, same-old"
here, but I am really curious as to any "real world" experiences that
might be out there in the matter of elevated radials, vs. those that are
simply laid atop the ground...
(A) Is it true that a couple of elevated radials are just as effective as
the "optimum" amount of buried ones...?
Probably not a "couple", but almost certainly in small systems a few
elevated radials are better than the same number of buried radials.
Everyone would like this to be a "cookie cutter" answer, but the actual
results depend heavily on the soil and installation. Even N6LF warns over
and over that his data only applies for conditions like his.
(B) What is the "ideal" number of elevated radials that one should use...?
As many as you can. More never hurts the signal, it just is more work.
(C) How many elevated radials are "just enough"...?
It depends on the soil, the height, the antenna, and what you want.
(D) How high should these radials be...?
It depends on the antenna, soil, and installation. Radial height takes away
from the effective antenna height. Certainly the safest thing is about .05
WL , unless the antenna is really short and that takes away significant
radiator height.
(E) Would it be a requirement that I raise the feedpoints of my "L's" to
the same height as the elevated radials, or can I simply leave the bases
where they are now (at ground level) & simply slant the radials upward
with no effect upon performance...?
It probably doesn't make much difference.
(F) Is it OK to bend the elevated radials to fit property allotments...?
It depends on where they are bent. The best practice is straight and
symmetrical.
(G) What is the desirable length of an elevated radial...?
1/4 wave resonant length.
(H) Should any existing connections to real earth at the base of the "L's"
(i.e. a ground pipe) be completed severed with a system of elevated
radials...?
If the resonant radials are grounded to an earth ground, the system will
lose efficiency. This much is always the case.
Pick the particular story you like Eddy, that's what most people do. :)
Read the fine print though. N6LF, whose study is one of the most
comprehensive is a good source for that particular test condition. Most
people seem to miss this:
http://www.antennasbyn6lf.com/2012/02/elevated-radial-ground-systems-some-cautions.html
What he writes isn't often what people actually paraphrase.
73 Tom
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Topband Reflector
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