At 10:51 AM 3/23/98 -0700, n7cl@mmsi.com wrote:
>Everything works better over perfect ground. SNIP
In fact, if you really have perfect ground, zero radials
>is the optimum number.
Well, no it isn't. Referring to 'SE's EZNEC results, there was about 1db
gained from elevating the feedpoint and whatever radial system above the
salt water. Elevated feedpoint counts for something, whether it is over
brine or rock.
>
>>>Don't elevated radials give some near field advantage over
>>>standard ground radials when the ground is very lossy?
>
>It depends on how many radials you are talking about. I think a
>good case can be made that a system with four elevated radials
>could suffer less total loss than a system with four radials
>laying on the ground surface.
I believe all this depends on what ground you are blessed with. Over poor
ground, my experiments to date indicate four elevated, resonant radials will
outperform at least a dozen on the ground. Perhaps if I were living in
Ohio, or somewhere else where typical ground conductivity is better, I would
do better to have the extra vertical length and run radials on the ground.
But here in the Appalachians, elevating feedpoint and radials gives me at
least some isolation from the very lossy ground, which I improve as I can.
Some argue that elevated radials that are fairly close to the ground are as
tightly coupled as those lying on the ground but I believe there is a
significant decoupling, comparatively speaking. Run a 160M dipole at 20
feet in the air, and then lay it on the ground and see how it works!
73
John K4IQ
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