Topband: Topband Antennas and saltwater

[W3HKK at roadrunner.com]

Thanks for a very enjoyable thread with multiple real-world examples
of the remarkable benefits of proximity to salt water. Sounds like
great fun. 

My own less-interesting case does not involve salt water, but does
involve my 52 ft vertical leg 1/4 wave radial INV-L out in the
backyard here in central Ohio. Midwest soil is generally considered of
average conductivity, and my site slopes about 15 degrees downwards
facing East and South, and about 15 degrees upwards facing West.

In 2009, When I erected my first 160m L, it was soley supported by a
15 ft tree ( the only one I had on my 3 acres of former farmland) fed
against an 8 ft ground rod. That was it. 15 ft high at the apex! The
far end sloped down to ground level, maybe 3-4 ft above the grass in a
SE direction. 

 I happily made many qsos around the US and began working the 160m
contests. Then one night I heard a 569 4X station calling CQ DX. On my
first call he replied and gave me a similar report. I was running
100w. Nearly fell off my chair. A few days later at my SR I heard a
weak JA calling CQ DX. He replied to my call with a 559. I had
suddenly worked the furthest dx I had ever worked on TB with a 15 ft
high INV-L and zero radials! 

Over the years I added 26 radials of between 35 (PL issues north) and
130 ft and my DX has improved to 185/165. I stopped adding radials
when I noticed the swr no longer increased, figuring I had reached the
optimum point for my soil cndx.

In summer, my radials are coiled up and hung from the walnut tree
during mowing season. Two years ago I failed to lay them out before
winter. The swr was rather different which I adjusted with a coke
bottle inductor at the base, and continued to operate with great
success, into VK/JA/EU/AF/SA. 

My point being that with decent soil conditions and very moist soil,
having no radials hasnt been a major deterrent to TB operating, altho
Im sure Id do better with them. How much better, I have no idea. 

So, at least for many Midwest stations, INV-L antennas can work well
even with a simple single ground rod. I found that stunning. So there
is hope for many landlocked TB operators.

PS Ive planted more trees and shrubs over the years, and noticed that
about 25% of them died. When the nursery dug them out, their roots
were waterlogged and the hole filled with water. Hence Im guessing the
tendency of a lot of ground water flowing down hill through the
shallow topsoil beneath my radial field, concentrated by layers of
clay beneath them, might be a factor working to my benefit. The
surface ground doesnt dry out until mid summer for hundreds of feet in
all directions.

	-----------------------------------------From:
topband-request at contesting.com
To: topband at contesting.com
Cc: 
Sent: Tuesday December 20 2022 12:38:07AM
Subject: Topband Digest, Vol 240, Issue 18

 Send Topband mailing list submissions to
 topband at contesting.com

 To subscribe or unsubscribe via the World Wide Web, visit
http://lists.contesting.com/mailman/listinfo/topband
 /> or, via email, send a message with subject or body 'help' to
 topband-request at contesting.com

 You can reach the person managing the list at
 topband-owner at contesting.com

 When replying, please edit your Subject line so it is more specific
 than "Re: Contents of Topband digest..."

 Today's Topics:

 1. Re: Antennas and saltwater (jh-mty at sbcglobal.net)

 ----------------------------------------------------------------------

 Message: 1
 Date: Tue, 20 Dec 2022 05:28:21 +0000 (UTC)
 From: "jh-mty at sbcglobal.net" 
 To: W7TMT - Patrick , "kq2m at kq2m.com"

 Cc: GEORGE WALLNER , Radio KH6O
 , "topband at contesting.com"

 Subject: Re: Topband: Antennas and saltwater
 Message-ID: 
 Content-Type: text/plain; charset="utf-8"

 I am an avid /M op, including on 160, quite active on 30M and higher
WARC bands.? I lived in Monterey, CA for around 10 years and visited
monthly for several more after that.? One of the greatest attractions
of the beautiful Monterey area was the Monterey Commercial Pier...a
long, elevated pier with buildings and fishing boat dock improvements,
along with a wonderful view.??
 None of the touristy advertisements for the "Fishermen's Wharf"
attractions mentioned that the elevation pattern of a "loaded" mobile
hamstick vertical antenna mounted high up on a metal van hatchback lid
18 feet over 20' deep salt water with downsloping, sandy bottom
leading to near-field abyssopelagic depths would produce peak gain at
18 degrees or less elevation.? The coveted "Brewster angle." As Frank,
W3LPL, observed in this thread:? "Radials cover a very small fraction
of the very large reflection zone (Fresnel zone) that produces low
angle radiation.? A vertical over a salt marsh or within about a
wavelength of salt water will produce 6 dB or more of gain at low
angles compared to a vertical with poorly conducting soil in its
reflection zone."
 On that wharf, I worked maybe 100 rare countries on 40, 30, 20, and
WARC bands competing with landlocked, high-power stations with major
beams and low-band wire arrays.? Worked VQ9 and other Indian Ocean
countries on the antipode, FR7, lots of southern African stations on
30M and 20M, and even some EU on 40M phone.? Heard most continents on
160M including EU, but couldn't work many countries on top band with
my? low power 100W IC-706MIIG (got some Central America, Oceana,
Alaska, east coast US and Canada, etc.).
 I took some friends on the ride to the wharf hearing very little over
the land, but an entire unheard world opened up when driving over the
ocean on the wharf, with signal strengths building on the wharf
approach and peaking as the water depth underneath increased.? I do
miss that wharf and will return QRV when I visit the Peninsula.
 John W6UQZ??
 ?
 ? ??
 ? ??
 On Monday, December 19, 2022 at 04:18:48 PM PST, kq2m at kq2m.com 
wrote:

 In 1990 I was visiting Antigua (V2) for 2 weeks.? I had a Butternut
HF6V
 with 160 coil and I mounted it on a 3' piece of copper pipe in a
 secluded part of the beach near the rocks about 2' above the
waterline,
 with about 30 short radials attached to it.

 At some point in the middle of the night, I noticed that I began to
hear
 what sounded like "swishing" sounds, not loud but persistent, for a
few
 hours and then it stopped.? The swr and resonant freq. on 80 and 160
 changed slightly but not enough to matter.? Curious, I went out just
at
 dawn and noticed that the radials were all in a clump and riding on
the
 water like the tentacles of a Man 'O war.

 During the night the tide came up about 3'vertically and the bottom
of
 the vertical was immersed in the water along with the radials which
were
 then washed into a mess.? That apparently was the "swishing" sound I
had
 heard.? LOL!? The performance was excellent the sounds were cool, the
 only time that I have ever heard them.

 The salt water effect was so remarkable that I could hear a 3W
station
 round the clock on 15M for several days - but he couldn't hear me
except
 in the daytime.? The EU stations were absurdly loud on 80 cw and I
heard
 several levels of Russian stations that I never heard before or since
 from W1.

 I had a similar experience with a 14AVT vertical stuck in the oil
sands
 of Aruba in January 1986 when I was the first to activate P4.? The
 vertical was not as good and it was planted 100' back from the water,
 but the water table was high and water was in the beach sand only 1'
 down and the copper pipe was stuck into that (there was also oil just
 underneath the surface in the water - I'm not sure if that helped or
 not.)

 Even though it was the bottom of the sunspot cycle, the LP JA signals
on
 40 at Sunset were INCREDIBLE!,? often S9 - S9 + 20 and the pileup of
 JA's literally drowned out the pileup of Europeans for about an
hour.?
 LOL!

 73

 Bob, KQ2M

 On 2022-12-19 17:18, W7TMT - Patrick 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  On
 > Behalf Of GEORGE WALLNER
 > Sent: Monday, December 19, 2022 14:19
 > To: Radio KH6O ; topband at 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

===========================================_________________ [1]


Links:
------
[1] http://blog.se0x.info/?p=3442#more-3442%3Cbr