In a message dated 1/8/2001 4:21:34 PM Eastern Standard Time,
alwilliams@olywa.net writes:
> Can Towertalkers explain why antennas over salt water is such an
> improvement?
>
> It seems to me that if all of the RF directed downward is reflected upward,
> by the salt water, that is only a 3db improvement in the RF being directed
> upward!
>
> What else is happening?
>
> k7puc
>
>
Hi Al,
briefly, main reasons are:
1. Salt water "ground" provides low loss return in the immediate vicinity of
the (vertical) antenna, which reduces losses in the ground, efficiency is
better especially with fewer radials, as compared over "regular" ground.
2. Far field and formation of the (low angle) pattern allows very low angles
of radiation and very little obstruction for the waves and it is dead QUIET,
nothing out there except perhaps lost ship.
So you gain better efficiency from antennas and coverage of low angles. In
real life this adds up to about 10 - 15 dB improvement over lousy ground
inland.
For more info and experiences see
http://pages.prodigy.net/k2kw/
I asked if anyone compared few radials vs. many radials on the beach etc.
What I am getting is answers to question I didn't ask :-) I guess my English
no good :-(
Yuri, K3BU
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