Re: Topband: Antennas and saltwater

[jh-...@sbcglobal.net]

 On some of my wharf visits, I would attach a lug to the base of the hamsticks 
with a long piece of braided copper wire soldered to it with metal washer and 
other weights attached to the far end, thinking that I would increase the 
saltwater ground coupling effect.
That really didn't pan out and was not much improvement.  However, twice some 
tourists came up and began hauling on my wire, thinking that a Dungeness crab 
might be on the other end (LOL).
Thinking back, I should attached a dang chicken leg to that wire end and caught 
me some tasty crab!! 
On Monday, December 19, 2022 at 09:29:42 PM PST, jh-...@sbcglobal.net 
 wrote:  
 
  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, k...@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 

Re: Topband: Antennas and saltwater

[Boye Christensen via Topband]

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  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 <
radio.k...@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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Re: Topband: Conditions for Stew Perry Contest

[samjos]

Here in Pennsylvania propagation to Europe was almost nonexistent. Caribbean
was ok, but not great. I did have a period of time where propagation to the
Pacific Northwest was good. Regardless, I always enjoy the SP contest and
had a great time.

Sam(N3XZ)

-Original Message-
From: Topband  On Behalf Of
Roger Kennedy
Sent: Monday, December 19, 2022 5:24 AM
To: topband@contesting.com
Subject: Topband: Conditions for Stew Perry Contest


I came on about 4 times during the night, but propagation this side of the
pond was really poor. 

NA Stations that are normally over S9 were around S5 . . . so couldn't hear
weaker signals at all. Even Europeans weren't very strong.

I did mange to work 16 NA stations, including Colorado and Virgin Islands.

73 Roger G3YRO


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Re: Topband: Antennas and saltwater

[GEORGE WALLNER]

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  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 <
radio.k...@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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Re: Topband: Radials, EZNEC and far field

[donroden]

Possibly  Bouvet in January...

W4DNR

On 2022-12-19 7:17 pm, Brian D G3VGZ wrote:


One other situation, above large quantities of dry ice, Antarctica or
perhaps Greenland.

Frank W3LPL  wrote:

Radials have no useful effect in improving low angle radiation, low 
angle
radiation from vertical antennas is determined almost entirely by 
highly

conductive soil or salt water in the large reflection zone.

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Re: Topband: Radials, EZNEC and far field

[Brian D G3VGZ]

One other situation, above large quantities of dry ice, Antarctica or
perhaps Greenland.

Frank W3LPL  wrote:

> Radials have no useful effect in improving low angle radiation, low angle
> radiation from vertical antennas is determined almost entirely by highly
> conductive soil or salt water in the large reflection zone.
> 


-- 
Brian D 
G3VGZ
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Re: Topband: Radials, EZNEC and far field

[Artek Manuals]

Soil conductivity plays a much bigger role than most of us realize and 
the "over salt water" is the gold standard`. As noted by a few other 
respondents radials are certainly helpful but for those of who live on 
quartz plains (sand) far from the ocean the far field losses can not be 
totally overcome by copper plating your yard in a 130ft circle




Dave
NR1DX



On 12/19/2022 5:50 PM, Ignacy Misztal wrote:

Do more radials on a 160m vertical bring more improvements than shown
by simulation?

Most simulations, e.g. by EZNEC, show that going above 32 radials on 160m
brings minimal improvement, say 1 db to 2 max. Even for low angle signals.

On the other hand, some really loud stations on 160m, that are 5-10 db 
above

the crowd, use a massive amount of radials. This is for inland stations,
far away from salt water.

Is there any discrepancy between modeling by EZNEC and real life
performance with the number of radials? Does adding radials beyond 32 help
much for low angles?

Any real story?

I have a shunt-fed 100 ft tower with 36 100ft radials. It is vastly
inferior to a 40 ft high inv L with 1 radial by salt water that hears DX
loud 2 hrs before the sunset. I am wondering whether by expanding to 50
200ft radials would narrow the difference.

Ignacy NO9E
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--
Dave manu...@artekmanuals.com www.ArtekManuals.com

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Re: Topband: Antennas and saltwater

[W7TMT - Patrick]

I only deploy it when needed. I’m lucky to be able to put antennas up at all so 
they go up on contest weekend Fridays and come down on Monday.  I do leave the 
ground hanging over the side and lower it into the water as needed to be used 
with the insulated back stay.

It’s a balancing act doing this from a boat.

W7TMT

From: Mark Schoonover 
Sent: Monday, December 19, 2022 4:27:59 PM
To: W7TMT - Patrick 
Cc: GEORGE WALLNER ; Radio KH6O ; 
topband 
Subject: Re: Topband: Antennas and saltwater

I did the same thing unfortunately all the sacrificial zincs disappeared in a 
few months.

On Mon, Dec 19, 2022, 16:18 W7TMT - Patrick 
mailto:w7...@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 
mailto:outlook@contesting.com>>
 On Behalf Of GEORGE WALLNER
Sent: Monday, December 19, 2022 14:19
To: Radio KH6O mailto:radio.k...@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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Re: Topband: Antennas and saltwater

[Mark Schoonover via Topband]

I did the same thing unfortunately all the sacrificial zincs disappeared in
a few months.

On Mon, Dec 19, 2022, 16:18 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@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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Re: Topband: Antennas and saltwater

[kq2m]

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@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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Re: Topband: Radials, EZNEC and far field

[Frank W3LPL]

Hi Ignacy -

There's little hope that a vertical antenna hundreds of miles
from salt water can ever close the gap with an antenna built over
a salt marsh or within about a wavelength of salt water.

The purpose of radials is reduce losses in the power transfer
between a feedline and a vertical antenna. Their effectiveness is
best measured by measuring the RF current at the base of the vertical.
Highly effective radial systems produce significantly more RF current
in the vertical than a sparse radial system.

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. 

Radials have no useful effect in improving low angle radiation,
low angle radiation from vertical antennas is determined almost
entirely by highly conductive soil or salt water in the large
reflection zone.

73
Frank
W3LPL




- Original Message -
From: "Ignacy Misztal" 
To: "topband" 
Sent: Monday, December 19, 2022 10:50:53 PM
Subject: Topband: Radials, EZNEC and far field

Do more radials on a 160m vertical bring more improvements than shown
by simulation?

Most simulations, e.g. by EZNEC, show that going above 32 radials on 160m
brings  minimal improvement, say 1 db to 2 max. Even for low angle signals.

On the other hand, some really loud stations on 160m, that are 5-10 db above
 the crowd, use a massive amount of radials. This is for inland  stations,
far away from salt water.

Is there any discrepancy between modeling by EZNEC and real life
performance with the number of radials? Does adding radials beyond 32 help
much for low angles?

Any real story?

I have a shunt-fed 100 ft tower with 36 100ft radials. It is vastly
inferior to a 40 ft high  inv L with 1 radial by salt water that hears DX
loud 2 hrs before the sunset. I am wondering whether by  expanding to 50
200ft radials would narrow the difference.

 Ignacy NO9E
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Re: Topband: Antennas and saltwater

[W7TMT - Patrick]

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@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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Topband: Radials, EZNEC and far field

[Ignacy Misztal]

Do more radials on a 160m vertical bring more improvements than shown
by simulation?

Most simulations, e.g. by EZNEC, show that going above 32 radials on 160m
brings  minimal improvement, say 1 db to 2 max. Even for low angle signals.

On the other hand, some really loud stations on 160m, that are 5-10 db above
 the crowd, use a massive amount of radials. This is for inland  stations,
far away from salt water.

Is there any discrepancy between modeling by EZNEC and real life
performance with the number of radials? Does adding radials beyond 32 help
much for low angles?

Any real story?

I have a shunt-fed 100 ft tower with 36 100ft radials. It is vastly
inferior to a 40 ft high  inv L with 1 radial by salt water that hears DX
loud 2 hrs before the sunset. I am wondering whether by  expanding to 50
200ft radials would narrow the difference.

 Ignacy NO9E
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Re: Topband: Antennas and saltwater

[GEORGE WALLNER]

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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Topband: Antennas and saltwater

[Radio KH6O]

> Ideal is if you can run some RG58 out to the beach and plunk it next to the
> water.  Also use 4 radials there.
> Enjoy.
> Ed  N1UR

Ed's comment reminds me of the AM broadcast band vertical antennas
mounted on concrete foundations located in the back-waters of San
Francisco Bay -- directly atop salt water mashes. What an outstanding
configuration!

Do they even need radials?

73,
Jeff KH6O
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Re: Topband: Conditions for Stew Perry Contest

[uy0zg via Topband]

Hi

George


I have heard your signal confidently and have called many times. But all 
I heard from you was CQ CQ CQ


---
I have not heard stations from the U.S. (except K1KI and W1UE - very 
quiet + QSB). There were no conditions.




---
Nick, UY0ZG
http://www.topband.in.ua

GEORGE WALLNER писал 2022-12-19 16:46:

I was operating /MM from St. Martin (FK88) and both the NA and EU
stations were weak. OK2CF, who is normally a solid S7 in FL was barely
above the noise. Conditions were either very poor or everybody was in
the QRP category. The only strong signals were form the Virgin
Islands.
73,

George,
AA7JV


On Mon, 19 Dec 2022 10:23:49 - "Roger Kennedy"  wrote:
I came on about 4 times during the night, but propagation this side of 
the
pond was really poor. NA Stations that are normally over S9 were 
around S5 . . . so couldn't hear

weaker signals at all. Even Europeans weren't very strong.

I did mange to work 16 NA stations, including Colorado and Virgin 
Islands.


73 Roger G3YRO


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Reflector

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Re: Topband: Conditions for Stew Perry Contest

[GEORGE WALLNER]

I was operating /MM from St. Martin (FK88) and both the NA and EU stations 
were weak. OK2CF, who is normally a solid S7 in FL was barely above the 
noise. Conditions were either very poor or everybody was in the QRP 
category. The only strong signals were form the Virgin Islands.

73,

George,
AA7JV


On Mon, 19 Dec 2022 10:23:49 - "Roger Kennedy"  wrote:

I came on about 4 times during the night, but propagation this side of the
pond was really poor. NA Stations that are normally over S9 were around S5 . . 
. so couldn't hear
weaker signals at all. Even Europeans weren't very strong.

I did mange to work 16 NA stations, including Colorado and Virgin Islands.

73 Roger G3YRO


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Topband: Conditions for Stew Perry Contest

[Roger Kennedy]

I came on about 4 times during the night, but propagation this side of the
pond was really poor. 

NA Stations that are normally over S9 were around S5 . . . so couldn't hear
weaker signals at all. Even Europeans weren't very strong.

I did mange to work 16 NA stations, including Colorado and Virgin Islands.

73 Roger G3YRO


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