Hello friends and foes of elevation,
Belonging to the silent majority of those who have followed the discussion on
elevated vs. grounded radials with great interest I don't feel really satisfied
as to the results of the issue. I'd like to suggest a simple experiment that
might give some helpful enlightenment.
If I had the space I would place two (to begin with) resonant elevated radials
in exactly opposite directions and switch the braid of the coax feedline of my
inverted-L (17m vertical + abt 35 m horizontal) between my grounded radials and
the elevated ones (keeping the feedline isolated from ground by a sufficient
number of ferrite beads). FS measurements outside the near field and/or S-meter
reports of some reliable hams in the immediate neighbourhood should show the
difference in performance with an accuracy of better than one db.
I'm well aware of the fact that the performance in the "elevated mode" is
influenced by the quality of the ground underneath (e.g. by the radial system
buried). I wouldn't worry too much about that as long as the elevated radials
improved the performance of my system to an extent that would make up for
quarreling with my XYL about messing up her garden (fortunately my small lot
here saves me that trouble).
I wouldn't expect that anybody with an elaborate radial system (how many of us
can really manage?) can actually gain anything before getting the elevated
radials a quarter wavelength above ground, but it might be interesting to find
out how poor your ground system must be before it is worthwile replace it by an
elevated system relatively close to ground.
Perhaps there will be a few in the parish of us topbanders who have the space
and the stamina to try such an experiment. As the quality of your ground
systems
are surely quite different, the results of these experiments will (hopefully)
yield more practical value than any theoretical discussion or computer modeling
(however fascinating that may be). Perhaps the outcome might be a further
incentive to find out more about optimizing vertical systems for all those who
can just dream of burying 60+ 260 ft. radials on their lot.
Being unable to try it myself I'd very much like to volunteer in collecting the
data and summarizing the results.
Greetings from Germany, Uli DJ2YA/N2YA
s-mail: Ulrich Weiss, Am Birkenstrauch 15, D-57334 Bad Laasphe
e-mail: dj2ya@t-online.de MYBBS: DJ2YA@DB0BID
tel: +49-2752-6462 FAX: +49-2752-2204
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