---- Greg - ZL3IX <zl3ix@inet.net.nz> wrote:
> Hi Eric,
>
> I am interested in a statement in your paper, "Beverages don't work over
> high(ly) conductive earth"
>
> By "not work", do you mean
>
> * Low RDF?
> * Pattern skewing?
> * Low output?
>
> I have a set of remote Beverages over quite high conductivity earth.
> They seem to work OK, but the output is lower than I would expect over
> poorer soil.
>
> 73, Greg, ZL3IX
This may be very simplified. I am far from a Beverage expert, but it was
explained to me once that the Bev works well over poorly conducting
soil because the wavefront is no longer just vertically oriented, as it
travels down the length of the antenna wire; but rather is retarded,
causing a forward tilt in the wavefront. This forward tilt then will
induce a RF current down the length of the wire, which sums up at the
end (where the RX is). IOW instead of just a vertical field, there is
both a vertical and a smaller horizontal field, and the poorer the soil,
the greater horizontal field induces the antenna current you need.
>From this I'd guess that the result is indeed lower output level.
Hope someone can give a proper answer (I haven't tried to research it)
-Bob k2euh
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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