To: <topband@contesting.com>
>Date: Tue, 22 Oct 1996 11:45:54 -0700 (PDT)
>X-Sender: eldridge@mail.cyberstore.ca
>From: eldridge@whistler.net (Bob Eldridge)
>Sender: owner-topband@akorn.net
>Precedence: bulk
>
>Tried to send this privately, but it bounces.
>
You are the second person to complain about bounced mail. I'll have to
cattleprod the sysad guys to see whats different recently. I still get a
_lot_ of externally originated e-mail tho...
>Eric:
>What's wrong with reducing the number of radials by making each one in the
>form of a Y, branching at the point where the spacing is less than .03?
Nothing at all. For a really large radial field, this is the way to do
it. Our main reference ground screen for antenna testing consisted of a
500 foot radius area of 2 inch welded intersection copper mesh made from #8
solid copper wire. From the outer edge of this mesh, every half meter a
radial ran outwards to a distance of a bit over 5000 feet. At each
distance outward where the radial to radial distance doubled, there was a
conductor welded between the radials and another radial was begun from the
center point between the existing radials on the lateral conductor. For
several years, I had a standing invitation for our local ham club to park
in the center of this field for field day. They never took me up on the
offer. Oh well...
>What do you consider the resonant frequency of a dipole (two opposed radials
>physically quarter wave radials) is likely to be?
>
Gosh, intuitively, I'd expect the resonant frequency to drop as it came
down from free space to near the ground. But right now, I can't recall
which way the radials we were testing with actually went. We _did_ have to
re-resonate them every time we tested a new elevation height. I wasn't
personally involved in making the adjustments so I don't really recall
which way the adjustment had to go (we did these tests right after Reagan
was elected the first time).
>Useful posting Peter.
>73
>Bob Eldridge VE7BS, RR1, Pemberton B.C. V0N 2L0
> eldridge@whistler.net
>
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