If the antenna stands in the salt-water or if you have a short, low
impedance connection to the water, you don't need radials.
During the VK9WWI DXpedition to Willis Islets, we installed a vertical on a
sand spit that was covered by water most of the time. We had 12 radials of
various lengths a couple of feet above the water. The antenna was fed via an
antenna coupler (tuner) mounted on its base. Every night during high tide
the waves knocked down and washed the radials into a tangled mess. For the
first three days we restored the radials every morning. But we never noticed
any difference between when the radials were up or when they were in a heap
at the base of the antenna. After three days we got rid of the radials. The
antenna had a heavy metal base which was always in contact with the water.
Ever since then, on various DXpeditions (TX3A, VK9GMW, PT0S, etc.), we
always put the antennas into the water (or the very edge of it where we
drive into the sand a grounding stake) and never bothered with radials.
Years ago I had a vertical at C6AGU standing in the water. During one night
a storm knocked it down. I reinstalled it up the beach about 75 feet from
the high tide line. I added 16 radials about 3 feet above the sand, I was
told that my 160 m signal was down 10 dB. I put the antenna back in the
water and had a good signal again. Whether the difference was really 10 dB,
I don't know. But it was substantial. (That was before RBN.)
73,
George,
AA7JV/C6AGU
On Mon, 19 Dec 2022 09:23:54 -0800 Radio KH6O wrote:
Ideal is if you can run some RG58 out to the beach and plunk it next to thewater.
Also use 4 radials there.Enjoy.Ed N1UR
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