I took my inspiration for the one turn counterpoise idea from HF Antenna For
All Locations page 155, Fig 11.9(m).
David G3UNA
> On 09 January 2022 at 17:09 CUTTER DAVID via Topband <topband@contesting.com>
> wrote:
>
>
> Thanks, Rick.
>
> My particular circumstances limit me to a small triangle of ground in the
> corner of a field and the FCP suits that very well. It would be interesting
> to know how the FCP compares to something well known, like a broadcast
> station ground.
>
> I like the idea of the spiral counterpoise: I experimented with a one turn
> counterpoise in EZNEC
> at 3 m above ground level. It looked workable but too big for my space, so,
> I could make that into a spiral and perhaps not be too concerned about
> symmetry. However, looking to Guy's idea of stacking the wires vertically so
> they shade the ground underneath might be worth a try. Compressing things
> always seems to limit bandwidth, so, that's something to be wary of.
>
> David G3UNA
>
>
> > On 09 January 2022 at 16:22 "Richard (Rick) Karlquist"
> > <richard@karlquist.com> wrote:
> >
> >
> >
> > On 1/9/2022 4:51 AM, CUTTER DAVID via Topband wrote:
> > > Hi Rob
> > >
> > > I see copper prices have doubled in the last year.
> > >
> > > My intention is to compare and contrast the cost and performance of short
> > > verticals over a large field of ground radials v the very modest amount
> > > of wire required for the FCP. In Guy's article
> > >
> >
> > This is a false dichotomy between FCP and a broadcast station ground
> > screen. The best use of wire is to have a small number of elevated
> > tuned radials with proper RF choking. As shown by N6LF, you can do well
> > with just 8 radials, about 100 feet long each. On 160 meters, they
> > should be 20 feet high for optimum performance. BTW, cheap aluminum
> > electric fence wire works perfectly for elevated radials Also consider
> > N6BT's single spiral radial configuration as an alternative to FCP.
> >
> > Rick N6RK
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