Hi Guys,
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...
My arthritic knees here are making the chore of rolling, & unrolling, my
seasonal 24-radials-per-"L"-element radials (I have THREE of them here!)
just that, i.e. a VERY painful chore...and barring the possibility of
there being a new "bionic" knee replacement(s) in my future, pray tell me:
(A) Is it true that a couple of elevated radials are just as effective as
the "optimum" amount of buried ones...?
** Define "a couple". As Ive said on here umpteem times everyones
soil/ground conditions are different. Im on a hilltop with solid granite no
more than 2' down and mostly less than that, a couple defined as 2 wouldnt
fly here very well.
(B) What is the "ideal" number of elevated radials that one should use...?
** When your antenna analyzer shows no change; in my case it was somewhere
between 16 and 32 as I simply doubled them and there was no change in 2:1
bandwidth or the impedance display.
(C) How many elevated radials are "just enough"...?
** Same as B unless you dont mind seasonal changes or have great soil. I
probably could have done OK with 8 but I believe my success was by paying
attention to the details and not throwing away an unknown amount of power be
it some fraction of a dB or not. Watching the bandwidth narrow is an eye
opener.
(D) How high should these radials be...?
** So you can drive a fire truck or 18 wheeler under them if necessary
otherwise 10-12' as a minimum.
(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...?
** Dont know. On mine I started at 10' and slanted to about 15' at a 45
degree angle as per Christman and then ran thru branches in the 15-20'
range.
(F) Is it OK to bend the elevated radials to fit property allotments...?
** I did, the West antenna was about 60' from the property line.
(G) What is the desirable length of an elevated radial...?
** Resonant if only 2-4. Mine are approximately 130' of #16 insulated
copper but since they all go thru branches that lowers the resonance; I
didnt bother measuring it. Ive seen some suggest tying all the ends together
into one big loop but havent seen any model to indicate it helps.
(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...?
** Yes. It helps to have a close in ground screen but not connected. For
lightning you can connect them and a couple of rods after the ferrite
isolation choke but be sure you have sufficient isolation to not affect the
antenna.
This morning I happened to work a NJ station with elevated radials that
almost pegged the S-meter on my 751A---the short distance between us
notwithstanding, obviously something was working very well for him there!
Thanks in advance & my vy
~73!~ de Eddy VE3CUI - VE3XZ
** Ive been an elevated fan since 1990, sure beats running on the ground
plus a screen and still not knowing if it really works as good as it could
as I had prior to that about 5 miles away and 500' lower.
Carl
KM1H
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