> I wonder what happened with experiments by Force 12 with verticals
> near salt water? Excellent article in CQ contest 3/98 and website of
> K2KW but no any info after that. Could anyone shed some light on this?
> Any experiences? How Far is too far?
Excluding groundwave, which we are not generally interested in,
there are two regions where salt water can help.
The first and the only major effect is close to the antenna in the
direction of propagation, mostly within a few wavelengths of the
antenna. This is the Fresnel (silent "S" in fresnel)) zone where the
pattern is being formed. The second is where the signal "bounces"
on the way to DX.
Saltwater does very little to help horizontally polarized antennas, it
mainly helps vertically polarized systems and mostly on higher
frequencies (unless the soil or the ground system is poor, in which
case it helps LF signals).
It does make a huge difference on vertically polarized ground wave
propagation if it occupies a significant part of the path distance.
The biggest effect of all is it makes us feel especially good about
our locations. Even freshwater lakes do that, although they have
poorer conductivity than most soils.
73, Tom W8JI
W8JI@contesting.com
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