Hi Charlie.
Naw, it's also the same if you hang it on a long strap or simply set it
down on the sand. The incoming distant signal is simply diminished at that
point. The essential modifying aspect is how much sand between you and the
water's edge. I'm sure it has a ghastly complex explanation.
What is not in doubt is the considerably increased strength of over-water
signals at the water's edge.
On Tue, Dec 20, 2022 at 6:17 PM <n0tt1@juno.com> wrote:
> >Having walked around on the beach with a battery K2 listening to incoming
> signals on a short antenna, walking 50 feet from the water drops signals
> multiple S units."
>
> Perhaps the handheld radio has a better ground connection, capacity coupled
> or not, through you and into the salt water + sand at the beach. Then,
> walking away from the beach
> that connection is greatly diminished.
>
> 73,
> Charlie, N0TT
>
> On Tue, 20 Dec 2022 08:58:23 -0500 Guy Olinger K2AV <k2av.guy@gmail.com>
> writes:
> > Having walked around on the beach with a battery K2 listening to
> > incoming
> > signals on a short antenna, walking 50 feet from the water drops
> > signals
> > multiple S units. Over the beach there is an absorption zone
> > starting at
> > the sand at water’s edge which goes higher and higher the farther
> > from the
> > water. This isn’t EZNEC, just observation on Core Banks, NC during
> > a number
> > of IOTA contests. Very easy with all those signals to hear what was
> > going
> > on.
> >
> > On 40m there was a big difference between a doublet at 40’ and
> > 50’, back
> > from the beach about 200’.
> >
> > Apparently sand wetted with salt water is quite lossy.
> >
> > But even not optimal at the beach smacks the snot out inland
> > locations.
> > Which IMHO explains the wide variety of beach-based reports.
> >
> > Also a very short vertical radiator away from water’s edge will
> > not hear as
> > much as a tall one as the tall wire has more intercept outside the
> > absorption zone next to the sand.
> >
> > It’s really quite a complex subject.
> >
> > 73, Guy K2AV
> >
> > On Tue, Dec 20, 2022 at 7:28 AM <n4is@comcast.net> wrote:
> >
> > > Hi Frank
> > >
> > > You wrote " . A vertical over a salt marsh or within about a
> > wavelength of
> > > salt water will produce
> > > 6 dB or more of gain at low angles compared to a vertical with
> > poorly
> > > conducting soil in its reflection zone
> > > "
> > >
> > > The assumption that "next to the water" is the same as "in the
> > water" , is
> > > a
> > > not right. It is not the same !
> > >
> > > I listen to George signal with vertical "in the water " and the 10
> > db
> > > difference in signal is real. Moving the antenna on the beach and
> > you lose
> > > 10 db or even more on practice, not on paper.
> > >
> > > I see that on my S meter more than a dozen times.
> > >
> > > George has a vertical on his house in Miami, the ground plane is
> > just a
> > > plate down the water. The vertical is made with fiberglass pole
> > 18m high.
> > > My
> > > antenna is a full size vertical with a good radial system over the
> > > Everglade
> > > land, if I dig 2 Ft I have water from the Everglade underground
> > river.
> > >
> > > George can run a pile up from Europe with 10W, I can keep up with
> > him
> > > running legal limit power. We are talking about 160m only.
> > >
> > > 73's
> > > JC
> > > N4IS
> > >
> > > _________________
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> > > Reflector
> > >
> > --
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> > Reflector
> >
>
>
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