> "Hugh Valentine" <hsvdds@juno.com> wrote:
>160M inverted "L" antenna...a radial system of 20 >radials, half 33' and half
>133' in length and ... an 8' >ground rod into the salt marsh ... and connects
>the >radials and the Salt water ground Rod together.
>
> Should Oval..
> 1) Connect his Ground rod in salt water to his radials
> 2) Use radials only and forget his Ground rod
Hugh,
I don't claim to be an "antenna expert". My observations
with similar configurations and my intuition suggest the
following:
a) The capacitance of the radial system to the salt-water
(saturating the salt-marsh) provides a lower impedance
path than a single ground rod. Therefore the ground rod is
not doing much for RF, but it may be useful for lightning
protection. (Assuming the radials are laid on the ground
or are very close to it.)
b) If there were multiple ground rods to provide a low
impedance path to the salt-water, there would be no need
for the radials.
c) Having both is the best: a 20 radial field is marginal
and marshes can dry out, etc.
On a number of DXpeditions we mounted inverted L antennas
standing in salt-water or on salt-water saturated sand. We
initially installed radials. Often the waves would wash
away these radials but we could never tell the difference!
I hope this helps,
73, George, AA7JV
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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