I run an 80' high vertical on 160M from my sailboat in the saltwater of Puget
Sound/Salish Sea near Seattle. After experimenting with a number of different
saltwater connections I've simplified it to a single piece of 1/2" dia. copper
pipe 10' long and tapped in the middle. I hang it horizontally over the side
just below the water surface. Works great.
I recently ran across a post by SE0X running an 160/80M vertical on a floating
dock who uses two lengths of suspended pipe. His RBN testing suggested that
adding a second one made a difference. Details here:
http://blog.se0x.info/?p=3442#more-3442
73
Patrick, W7TMT
-----Original Message-----
From: Topband <topband-bounces+w7tmt=outlook.com@contesting.com> On Behalf Of
GEORGE WALLNER
Sent: Monday, December 19, 2022 14:19
To: Radio KH6O <radio.kh6o@gmail.com>; topband@contesting.com
Subject: Re: Topband: Antennas and saltwater
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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