Good Day Again All,
Well, I've done my best to summarize all the respondents' comments in the
matter of elevated vs. ground-mounted radials---and I'll try now to summarize
these in a single-page format for benefit of all to see...
The results are certainly interesting, and some are as different from one
another as we might be physically!
In any event---and FWIW---here goes:
(A) Is it true that a couple of elevated radials are just as effective as the
"optimum" amount of buried ones...?
-It depends.
-Don't know.
-Don't know.
-If 2 or more are used, maybe.
-It depends.
(B) What is the "ideal" number of elevated radials that one should use...?
-It depends upon their height.
-2.
-2 to 4.
-7 to 8.
-1 to 5.
-2.
-8.
-1 to 2.
-16 to 32.
-16 to 32.
-The more the better.
-Any amount, but use pairs (ex. 2 to 4, 6 to 8, etc.).
(C) How many elevated radials are "just enough"...?
-Enough to overcome ground losses & establish resonance.
-2.
-2
-2.
-2.
-4.
-4 (8 is overkill).
-1.
-32.
-8.
-Depends upon soil quality
(D) How high should these radials be...?
-The higher the better to clear pedestrians, animals, etc.
-10'.
-6' to 8'.-6' to 8'.
-12' to 14'.
-7' to 8'.
-6' to 15'.
-20'.
-6' to 10'.
-8'.
-10' to 12'.
-20'.
-1' to 10' (but the higher the better).
(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...?
-"Gull wing" arrangement OK.
-Feed point should be 8' high.
-Not sure.
-Makes no difference.
-"Gull wing" OK.
-"Gull wing" OK.
-Not sure.
-Same height as radials (to minimize ground loss).
-Makes no difference.
-Optional.
(F) Is it OK to bend the elevated radials to fit property allotments...?
-Slight bends OK.
-Yes.
-Yes.
-Yes.
-Not sure.
-Not sure.
-OK, but gradual bends only.
-No.
-Yes.
-Best kept straight.
(G) What is the desirable length of an elevated radial...?
-Quarter wave.
-Quarter wave.
-Quarter wave.
-Quarter wave.
-Quarter wave.
-Quarter wave.
-Quarter wave.
-Quarter wave.
-Quarter wave.
-Quarter wave.
-Use short radials with a common coil.
-Quarter wave + height above ground.
(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 radials one quarter wave long, makes no difference.
-No ground.
-No ground.
-With a ground, there'll be noise on receive.
-NEVER ground.
-No ground.
-No ground.
-No ground.
-No ground.
-No ground.
Additionally, four respondents recommended using a choke balun at the
feedpoint...one person avowed that a single elevated radial was the equivalent
of 30 ground radials...another stated that 8 elevated radials were "super
good", but that even 1 to 2 would be good...another affirms that one simply can
not beat the optimal number of buried radials...
Several recommended this site as an excellent reference as well:
http://www.antennasbyn6lf.com/2012/02/elevated-radial-ground-systems-some-cautions.html
I personally haven't taken a look at it myself here, but it is most certainly
on my "to do" list!
I hope my effort here might help dissipate some of the "fog" surrounding
elevated radials, vs. ground-mounted ones---certainly there's stuff here that I
wanna digest still...and again, I thank one & all for their feedback, & trust
that I've done justice here to your many responses...
~73~ de Eddy VE3CUI - VE3XZ
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Topband Reflector
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