Don't forget to add a resistor, to avoid stadic building charge:
10Mohm or so
73 Boye
On 20-12-2022 03:17, GEORGE WALLNER wrote:
On boat you need to put a capacitor (22 nF or greater) in series with
the GND connection. That will stop DC from "melting" your sacrificial
anodes.
GW
On Mon, 19 Dec 2022 17:27:59 -0700 Mark Schoonover wrote:
I did the same thing unfortunately all the sacrificial zincs
disappeared in a few months.
On Mon, Dec 19, 2022, 16:18 W7TMT - Patrick <W7TMT@outlook.com> wrote:
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.comSubject: 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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