Re: Topband: Elevated Radials

[Jim Brown]

On 1/5/2024 11:32 AM, Frank W3LPL wrote:

Unless you live on a salt march (there aren't many in Ohio ,
horizontally polarized antennas are significantly more efficient than
verticals on every band except 160 meters, even if 80 meter horizontally
polarized  antennas ore only 70 feet high and 40 meter antennas are
only about 50 feet high.


YES! This is entirely consistent with an extensive modeling study I 
published about ten years ago on how horizontal and vertical antennas 
interact with ground. In essence, horizontal antennas care greatly about 
height but hardly at all about ground quality, while verticals are VERY 
strongly dependent on ground quality in both the near and far field.


The study allowed me to develop a Figure of Merit in dB for the height 
of horizontally polarized antennas on 80 and 40M. The study also showed 
that a quarter-wave is the optimum height for NVIS, and that only a few 
dB is lost up to a half-wave.


The study also showed that the typical multi-band HF vertical benefits 
from mounting at typical roof-top heights, provided that those that are 
essentially loaded/trapped quarter wave designs have at least a couple 
of radials per band. Two reasons for the benefit -- first, reduced 
ground losses, second a better vertical pattern.


The write-up I published of the study is here.

http://k9yc.com/AntennaPlanning.pdf

NCJ wanted to publish it, but HQ publishing couldn't deal with the 
graphs. It was peer-reviewed by sharp engineers when I presented it at 
an NCCC meeting. Vertical vs horizontal is quite consistent with my 
on-the-air experience. For a couple of years, I had a 160 dipole at 
about 120 ft in addition to a 100 ft Tee vertical with a lot of radials, 
and did a lot of comparisons. The dipole rarely beat the vertical. 
Another observation -- during the daylight hours of 160M contests, I can 
reliably work good stations up to about 800 miles with the Tee; with the 
dipole, never even a QRZ?  The logic is simple -- even at 120 ft, it's a 
low dipole on 160M. :)


73, Jim K9YC




_
Searchable Archives: http://www.contesting.com/_topband - Topband Reflector

Re: Topband: elevated radials, etc

[Rich Dailey]

I suppose I'm 'Mr. Bad Example' of how to not think too much about my 160m
inverted L. Verily I have spent way more time trying to figure out how I
was going to get the wire as high as I could, and the horizontal portion as
short as possible (HINT: at my age, climbing gaffs bad, crossbow good). The
result is about 85' up to a tree limb (6-8' from the tree trunk), then out
horizontally to the east for the rest. For ground radials, each season I
lay out six quarter wavelengths (roughly) of old computer CAT cable with
all the wires soldered together on both ends. I literally pull them out
across the pasture (once the cows are gone for the winter), and loosely tie
them to fiberglass stakes at the ends to keep them somewhat straight. With
the height of the grass, they are what I would guess to be 6-8 inches
'suspended' over the dirt.

We have a LOT of deer; each hunting season this place becomes a refuge for
them. Rarely do I have a deer trip over a ground radial enough for me to
have to do anything about it. I'll go so far as saying they get to know
they are there, and walk around, or jump over them.  The only recurring
deer trouble I had was when I had my beverages at 6'. Raising them to 7-8'
solved that completely. Not a single deer issue for the past two 160m
seasons.

The inverted L works wonderfully as my xmit antenna, and is very tolerable
on rx, using a noise antenna and mfj-1025.  Six radials laying on the
ground works for me.
And no, they do not come together in a perfect ring surrounding the
feedpoint. I use a giant split nut about 8 inches away from the vertical
wire to which they are all attached and placed under a tupperware
container. The whole thing is happy with 1kw, although I most typically run
100-200 watts.

I'm sure I have horrible interactions between my L's, the beverages, and
maybe even the 5-circle a bit.  But it is still fun, and I adore 160m, and
BCB dx'ing. Even during the peak, such as it is.

I do enjoy reading the threads here, but rarely chime in. Thanks to all who
are diving deep on these topics. Heck of a knowledge base here. Many tnx to
VE6WZ, et al. for your contributions that stoke the magic fire of this band.

And many tnx to all for the Rudy Severns info. I remembered coming across
that several years back, but lost in the bookmarks.

~ tu de N8UX
_
Searchable Archives: http://www.contesting.com/_topband - Topband Reflector

Re: Topband: Elevated Radials

[Frank W3LPL]

Hi Bob,

That's a superb antenna farm you've grown in central Ohio!
Congratulations!

Your elevated systems of four radials would work even better with
more radials. You can prove that to yourself by measuring the current
feeding each radial, the currents will vary significantly depending
on the unique environment if each radial.  Doubling the number of
radials will divide the current much more evenly among 8 radials.

Unless you live on a salt march (there aren't many in Ohio ;),
horizontally polarized antennas are significantly more efficient than
verticals on every band except 160 meters, even if 80 meter horizontally
polarized  antennas ore only 70 feet high and 40 meter antennas are
only about 50 feet high.  

Unless you live on an Ohio salt marsh, verticals suffer very badly
on 20 meters and above because of inefficient ground reflections
in the far field of the antenna -- well beyond the end of the radials --
at the necessary low radiation angles of radiation on those bands.
That's why your simple Moxon performs so well on 10 meters
compared to your verticals.

73
Frank
W3LPL


- Original Message -
From: w3...@roadrunner.com
To: "topband@contesting.com" 
Sent: Friday, January 5, 2024 11:12:14 AM
Subject: Re: Topband: Elevated Radials

Moved onto 3 rural acres about 14 yrs ago. Only had one (15') tree on
the whole property, AND I had sold my yagis and tower about five years
earlier. So I went with monoband GPs on 40-30-20-17-10.
All were 9-10 ft above ground and used 4 elevated radials.

I borrowed a used 4BTV, set it up with the included 24 radials on the
ground. Comparing it to my 20m GP showed the monoband GP to be 0.5-1.0
S-units better. So I convinced myself the 4 elevated #14 solid copper,
pvc jacketed radials were worth it.

A few years later I expanded the 40m and 20m GPs into 2 el phased
arrays, and the nice 3dB gain punches into Asia quite well. Plus the
fat forward and rear lobes give me about 300 degree useful coverage,
with a couple of nulls in between.

The only deer damage Ive had is to my SAL30 RX antenna which I only
put up 3-4 ft above grade.
(should have put it up 8 ft.). 

Elevated radials work very well indeed. 

OTOH, my 160/80m INV-L's share a common 26 radials that I roll up for
mowing season, and uncoil onto the ground for winter. 

PS Built a home brew Moxon for 10m last year and it is a good notch or
two above a single GP. 
Added a 3 el vert (Bobtail curtain) for 12 which is working well but
not at a Moxon level. Worked Bouvet with my 30m GP, and Bhutan the
year before. so the elevated radials are bringing in the rare ones. 

-From:
topband-requ...@contesting.com
To: topband@contesting.com
Cc: 
Sent: Friday January 5 2024 12:00:43PM
Subject: Topband Digest, Vol 253, Issue 7

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 Today's Topics:

 1. Re: Using 4 - 6 elevated radials in lieu of 120 buried wires (Joe)

 --

 Message: 1
 Date: Fri, 5 Jan 2024 10:08:26 -0600
 From: Joe 
 To: Wes Stewart , "topband@contesting.com"
 , Jeff Blaine 
 Subject: Re: Topband: Using 4 - 6 elevated radials in lieu of 120
 buried wires
 Message-ID: 
 Content-Type: text/plain; charset=UTF-8; format=flowed

 I guess this list doesn't pass images sorry.

 Joe WB9SBD

 On 1/5/2024 9:55 AM, Joe wrote:
 > I beg to differ on the High Maintenance possibility.
 > I live in Southwest Wisconsin the Deer hunting capital of maybe the
 > world.
 > There are deer in my yard every day.
 > We have wind storms,
 > We have Ice storms, Bad ones like take down professional broadcast
 > tower Ice storms.
 >
 > Yet my 40 meter 1/4 wave vertical has been up for 20+ years.
 > The base is up 10 feet,
 > The radials act as sloping guy wires. the ends only 2 feet above
the
 > ground. So prime Deer attack prey.
 > ?It has yet to have issues from Deer or weather,
 > View from base looking up.
 >
 > And view? during a 60 Mph+ storm.
 >
 >
 > Joe WB9SBD
 >
 > On 1/5/2024 9:38 AM, Wes Stewart via Topband wrote:
 >> ? Not me.? My radials are all on the ground and they are all
 >> appropriately shortened.
 >>
 >>  On Friday, January 5, 2024 at 08:05:47 AM MST, Jeff
 >> Blaine? wrote:
 >> ? ? There is another practical issue here.? I would agree that
elevated
 >> radials can work great.? But in practice, MAINTENANCE of the
elevated
 >> radials is a

Re: Topband: Elevated Radials

[W3HKK]

Moved onto 3 rural acres about 14 yrs ago. Only had one (15') tree on
the whole property, AND I had sold my yagis and tower about five years
earlier. So I went with monoband GPs on 40-30-20-17-10.
All were 9-10 ft above ground and used 4 elevated radials.

I borrowed a used 4BTV, set it up with the included 24 radials on the
ground. Comparing it to my 20m GP showed the monoband GP to be 0.5-1.0
S-units better. So I convinced myself the 4 elevated #14 solid copper,
pvc jacketed radials were worth it.

A few years later I expanded the 40m and 20m GPs into 2 el phased
arrays, and the nice 3dB gain punches into Asia quite well. Plus the
fat forward and rear lobes give me about 300 degree useful coverage,
with a couple of nulls in between.

The only deer damage Ive had is to my SAL30 RX antenna which I only
put up 3-4 ft above grade.
(should have put it up 8 ft.). 

Elevated radials work very well indeed. 

OTOH, my 160/80m INV-L's share a common 26 radials that I roll up for
mowing season, and uncoil onto the ground for winter. 

PS Built a home brew Moxon for 10m last year and it is a good notch or
two above a single GP. 
Added a 3 el vert (Bobtail curtain) for 12 which is working well but
not at a Moxon level. Worked Bouvet with my 30m GP, and Bhutan the
year before. so the elevated radials are bringing in the rare ones. 

-From:
topband-requ...@contesting.com
To: topband@contesting.com
Cc: 
Sent: Friday January 5 2024 12:00:43PM
Subject: Topband Digest, Vol 253, Issue 7

 Send Topband mailing list submissions to
 topband@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-requ...@contesting.com

 You can reach the person managing the list at
 topband-ow...@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: Using 4 - 6 elevated radials in lieu of 120 buried wires (Joe)

 --

 Message: 1
 Date: Fri, 5 Jan 2024 10:08:26 -0600
 From: Joe 
 To: Wes Stewart , "topband@contesting.com"
 , Jeff Blaine 
 Subject: Re: Topband: Using 4 - 6 elevated radials in lieu of 120
 buried wires
 Message-ID: 
 Content-Type: text/plain; charset=UTF-8; format=flowed

 I guess this list doesn't pass images sorry.

 Joe WB9SBD

 On 1/5/2024 9:55 AM, Joe wrote:
 > I beg to differ on the High Maintenance possibility.
 > I live in Southwest Wisconsin the Deer hunting capital of maybe the
 > world.
 > There are deer in my yard every day.
 > We have wind storms,
 > We have Ice storms, Bad ones like take down professional broadcast
 > tower Ice storms.
 >
 > Yet my 40 meter 1/4 wave vertical has been up for 20+ years.
 > The base is up 10 feet,
 > The radials act as sloping guy wires. the ends only 2 feet above
the
 > ground. So prime Deer attack prey.
 > ?It has yet to have issues from Deer or weather,
 > View from base looking up.
 >
 > And view? during a 60 Mph+ storm.
 >
 >
 > Joe WB9SBD
 >
 > On 1/5/2024 9:38 AM, Wes Stewart via Topband wrote:
 >> ? Not me.? My radials are all on the ground and they are all
 >> appropriately shortened.
 >>
 >>  On Friday, January 5, 2024 at 08:05:47 AM MST, Jeff
 >> Blaine? wrote:
 >> ? ? There is another practical issue here.? I would agree that
elevated
 >> radials can work great.? But in practice, MAINTENANCE of the
elevated
 >> radials is a non-ending headache.? Around here we have deer and
ice and
 >> wind and on and on.? I ran various 40m 4SQ elevated radial schemes
for
 >> years and eventually went to an in-ground installation because I
was
 >> tired of the hassle.
 >>
 >> You are probably a far better mechanical and electrical hand than
I am.
 >> But this maintenance aspect of elevated radials is something I
don't
 >> think gets enough mention.
 >>
 >> 73/jeff/ac0c
 >> alpha-charlie-zero-charlie
 >> www.ac0c.com
 >>
 >> On 1/5/2024 8:42 AM, Wes Stewart via Topband wrote:
 >>> I was about to recommend Rudy's work. He is a prolific
experimenter
 >>> and writer; reading his stuff will answer almost anything you
ever
 >>> what to know about vertical antennas, ground systems and
receiving
 >>> antennas.
 >>> I have a folder on my hard drive with 30-40 of his papers.
 >>>
 >>>
 >>>
 >>> ?? ? On Friday, January 5, 2024 at 01:03:55 AM MST, Jim
 >>> Brown? wrote:
 >>>
 >>>
 >>> Some thoughts about that particular installation and why it
worked
 >>> well,
 >>> based on my study of Rudy Severns' excellent work on the topic.
 >> ?? _
 >> Searchable Archives:http://www.contesting.com/_topband? [1] -
Topband
 >> Reflector
 > _
 > Searchable Archives: http://www.contesting.com/_topband [2] -
Topband
 > Reflector

 --

 Subject: Digest Footer

 

Re: Topband: elevated radials question

[Greg Davis]

Thanks to all of you who replied to me with a lot of information to digest.

I believe I will improve my existing on-ground radial system as a starting
point, see if I can switch over to a T-top vertical between two trees
instead of my current inverted J over the top of one tree. And, of course,
try to improve my RX situation.

Hope to work you all on 160m soon.

73 de Greg N3ZL

On Mon, Oct 25, 2021 at 12:04 PM Greg Davis  wrote:

> Hello Topbanders,
>
> I just got my 160m antenna back up after being off the band for a while,
> just in time for the pre-Stew this past weekend. It is an inverted "J" with
> I'd estimate 90ish feet more-or-less vertical over the tallest tree in my
> back yard. I've got a decent number of on-ground radials laid down from
> previous years, but I plan to add some elevated radials this season.
>
> There are a few things I'm not sure of. Do I raise the base of the vertical
> to the height of the elevated radials -- 48" inches or so? Do I leave it on
> the ground and slope up from the base of the vertical to reach the elevated
> height a short distance away? Is there any reason not to combine a mix of
> on-ground and elevated radials?
>
> Thanks in advance.
>
> 73 de Greg N3ZL
> _
> Searchable Archives: http://www.contesting.com/_topband - Topband
> Reflector
>
_
Searchable Archives: http://www.contesting.com/_topband - Topband Reflector

Re: Topband: elevated radials question

[List Mail]

I ran a top loaded vertical over elevated radials for about 10 years. I fed the 
vertical at the level of the radials, around 10 feet. There were eight radials, 
seven of which were ¼ wavelength and one was considerably shorter, as that 
property boundary limited me.
I then moved house, and ran the same with 4 x elevated radials for 160 m, and 4 
for 80 m.
Well, all I can say is that it worked. I moved my country score to around 140, 
which is quite an effort for Australia, but I became disillusioned with all the 
elevated radials cluttering the paddock. Several times one or more either fell 
down, or I tore them down when I was driving the tractor under them, because a 
horse had scratched his bum on a support pole and the wire sagged.
So, I resolved to put down a buried radial field, and for the past couple of 
years, I have 64 x 100 foot long buried radials. Much tidier!
A few points on elevated radials. As mentioned by others, you need to get them 
up a reasonable height. I had to put mine up clear of horses and vehicles in 
the paddock.
With four or fewer radials, they are very sensitive with tuning. More than 
four, and they are less so. Many more than four and you are likely to cause 
family disharmony.
Buried radials in the long run are tidier, but a lot of work. You can put them 
down one by one by cutting the turf with a spade and pushing the wire down with 
a stick. This disturbs the ground less than by trenching. With patience, you’ll 
get your maximum ground radial field down, and maintain a neat ground surface 
and family harmony.
And definitely work on arranging a receive antenna.
See you on Top!
73, Luke VK3HJ

Sent from Mail for Windows

From: Greg Davis
Sent: Tuesday, 26 October 2021 3:59 AM
To: topband@contesting.com
Subject: Re: Topband: elevated radials question

Grant and Joel,

Thanks for the feedback.

I have a stockpile of wire that's not doing me any good sitting in my
garage, so it sounds to me like probably the best thing is to add some more
on-ground radials (to some extent) and focus on improving my RX since I do
not yet have a dedicated RX antenna.

73 de Greg N3ZL
_
Searchable Archives: http://www.contesting.com/_topband - Topband Reflector

Re: Topband: elevated radials question

[Jim Brown]

On 10/25/2021 9:17 AM, Grant Saviers wrote:

Don't connect elevated radials to on/in ground radials.

There is a huge ground loss for 4ft high radials on 160m.  7ft is far 
better and 10 ft is pretty good.


When I first installed radials this low, there was, indeed, high ground 
loss. N6BT, an excellent antenna designer who has done extensive work on 
verticals, advised me that 16-20 feet was a minimum height, and when I 
raised them to about 20 ft, efficiency improved significantly.


There are "W" shaped radial feeds with the base near to the ground but 
IMO it is better to elevate the feedpoint to radial height and add a bit 
of wire to the top load to get back to resonance.


Radials can be a bit shorter than 1/4wl ~ 85% for 4, even shorter for 
more. see antennasbyn6lf.com  Or a single high Q inductor to shorten 
them more, but modeling is needed.


I've followed Rudy's advice and made them slightly shorter than a 
quarter wave.


73, Jim K9YC

_
Searchable Archives: http://www.contesting.com/_topband - Topband Reflector

Re: Topband: elevated radials question

[Greg Davis]

Grant and Joel,

Thanks for the feedback.

I have a stockpile of wire that's not doing me any good sitting in my
garage, so it sounds to me like probably the best thing is to add some more
on-ground radials (to some extent) and focus on improving my RX since I do
not yet have a dedicated RX antenna.

73 de Greg N3ZL

On Mon, Oct 25, 2021 at 12:04 PM Greg Davis  wrote:

> Hello Topbanders,
>
> I just got my 160m antenna back up after being off the band for a while,
> just in time for the pre-Stew this past weekend. It is an inverted "J" with
> I'd estimate 90ish feet more-or-less vertical over the tallest tree in my
> back yard. I've got a decent number of on-ground radials laid down from
> previous years, but I plan to add some elevated radials this season.
>
> There are a few things I'm not sure of. Do I raise the base of the vertical
> to the height of the elevated radials -- 48" inches or so? Do I leave it on
> the ground and slope up from the base of the vertical to reach the elevated
> height a short distance away? Is there any reason not to combine a mix of
> on-ground and elevated radials?
>
> Thanks in advance.
>
> 73 de Greg N3ZL
> _
> Searchable Archives: http://www.contesting.com/_topband - Topband
> Reflector
>
_
Searchable Archives: http://www.contesting.com/_topband - Topband Reflector

Re: Topband: elevated radials question

[Grant Saviers]

Don't connect elevated radials to on/in ground radials.

There is a huge ground loss for 4ft high radials on 160m.  7ft is far 
better and 10 ft is pretty good.


There are "W" shaped radial feeds with the base near to the ground but 
IMO it is better to elevate the feedpoint to radial height and add a bit 
of wire to the top load to get back to resonance.


Radials can be a bit shorter than 1/4wl ~ 85% for 4, even shorter for 
more. see antennasbyn6lf.com  Or a single high Q inductor to shorten 
them more, but modeling is needed.


An excellent coax choke is essential for elevated, the 4" K9YC #31 
design is great.


Grant KZ1W

On 10/25/2021 09:03, Greg Davis wrote:

Hello Topbanders,

I just got my 160m antenna back up after being off the band for a while,
just in time for the pre-Stew this past weekend. It is an inverted "J" with
I'd estimate 90ish feet more-or-less vertical over the tallest tree in my
back yard. I've got a decent number of on-ground radials laid down from
previous years, but I plan to add some elevated radials this season.

There are a few things I'm not sure of. Do I raise the base of the vertical
to the height of the elevated radials -- 48" inches or so? Do I leave it on
the ground and slope up from the base of the vertical to reach the elevated
height a short distance away? Is there any reason not to combine a mix of
on-ground and elevated radials?

Thanks in advance.

73 de Greg N3ZL
_
Searchable Archives: http://www.contesting.com/_topband - Topband Reflector


_
Searchable Archives: http://www.contesting.com/_topband - Topband Reflector

Re: Topband: Elevated Radials - will radials on ground help?

[James V Redding PE]

Some kind person got permission and put this copyrighted paper online:

https://www.okdxf.eu/files/Ground%20Systems%20-%20Brown,%20Lewis%20and%20Epstein%201937.pdf

Dr. Brown was noted for such things as having assistants erect a dipole,
connect a 50 KW transmitter, and take impedance measurements.

Also:

https://ipo.llnl.gov/sites/default/files/2020-07/NEC5%20Validation%20Manual%20092419.pdf

Has an extensive discussion (near the end) of radial systems.

All free access to read..

JIm/VEZ

On Tue, Dec 29, 2020 at 2:37 PM fmoeves  wrote:

> I was under the impression that If you have elevated radials and if you
> take even one to the ground you might as well move all to the
> ground..??Fred KB4QZH
>  Original message From: donov...@erols.com Date:
> 12/29/20  12:30 PM  (GMT-05:00) To: topband@contesting.com Subject: Re:
> Topband: Elevated Radials - will radials on ground help? Hi Clive, A second
> resonant radial is a good idea, but not because it might cancel
> horizontally polarized radiation. Why? Because -- just like a Beverage -- a
> horizontal wire close to the ground has no significant horizontally
> polarized radiation. Essentially all of the horizontally polarized
> radiation is lost to ground losses. 73 Frank W3LPL - Original Message
> -From: cl...@gm3poi.com To: donov...@erols.com, topband@contesting.com
> Sent: Tuesday, December 29, 2020 5:25:05 PM Subject: RE: Topband: Elevated
> Radials - will radials on ground help? Frank what about adding another
> radial to each vertical to cancel the Horizontal polarisation from the
> single radial. 73 Clive GM3POI -Original Message- From: Topband
>  On Behalf Of
> donov...@erols.com Sent: 29 December 2020 17:01 To: topband@contesting.com
> Subject: Re: Topband: Elevated Radials - will radials on ground help? Hi
> Dan, Your small lot is an ideal candidate for K2AV's folded counterpoise.
> Contact K2AV for guidance, he's helped countless successful users.
> www.k2av.com A few clarifications regarding radials and gain: Radials
> have absolutely nothing to do with gain. They only reduce ground losses
> within a fraction of a wavelength of the antenna. The realistic
> opportunities to further reduce losses are: - install the antenna on salt
> march like K3ZM and W1KM, or - install the antenna closer than one mile to
> sea water in the foreground of the antenna for at least a few miles in the
> most important directions. But you've already done that. Bravo! Good luck!
> 73 Frank W3LPL - Original Message - From: "Dan Flaig NP2J" <
> d...@np2j.com> To: donov...@erols.com Sent: Tuesday, December 29, 2020
> 4:41:40 PM Subject: Re: Topband: Elevated Radials - will radials on ground
> help? On 2020-12-29 10:06, donov...@erols.com wrote: > Hi Dan, > > An
> inverted-L with one elevated radial has lots of room for > improvement, >
> almost anything will improve what you now have. > > How much improvement
> you can achieve is mostly determined by site > limitations, copper wire
> expense, how much work you're able do > yourself or pay someone else to do
> for you. > > Eight radials, 70 feet long is the absolute minimum number of
> radials > if you lay them on the ground. Sixteen 80-foot radials will be
> much > better, > 32 100-radials will be significantly better than that.
> Finally 60 > 125-foot > radials will be within one dB of the best you could
> achieve. > > This is the classic reference: > >
> ncjweb.com/bonus-content/k3lcmaxgainradials.pdf > > If you continue to
> use resonant elevated radials, four is the minimum > number your should
> shoot for, but unfortunately its difficult to get > all > four elevated
> radials to carry similar amounts of current. Eight > elevated > radials is
> much better. > > The K2AV Folded counterpoise is another alternative to
> your > current single elevated radial. > > Good luck! > > 73 > Frank >
> W3LPL > > - > > From: d...@np2j.com > To:
> topband@contesting.com > Sent: Tuesday, December 29, 2020 1:58:53 PM >
> Subject: Topband: Elevated Radials - will radials on ground help? > > Hello
> fellow Topbanders! > > Had lots of fun in the Stew, thanks for the contacts
> everyone! > > Looking forward to the CQ160 and as always trying to find a
> way to > improve antenna performance so looking for advice > > I am
> currently using a pair of Inverted L's each having a single > elevated
> radial. > The feedpoint's and elevated radials are 10-12 feet above ground.
> > The soil is fairly rocky. > Also quite a bit of "Bush" growing fairly
> high except below elevated > radials where I have trimmed back t

Re: Topband: Elevated Radials - will radials on ground help?

[Jim Brown]

On 12/29/2020 11:37 AM, fmoeves wrote:

I was under the impression that If you have elevated radials and if you take 
even one to the ground you might as well move all to the ground..??Fred KB4QZH


Yes. Losses in elevated radials rise with poorly balanced currents. It's 
worth spending time studying N6LF's extensive writing about this.


73, Jim K9YC
_
Searchable Archives: http://www.contesting.com/_topband - Topband Reflector

Re: Topband: Elevated Radials - will radials on ground help?

[fmoeves]

I was under the impression that If you have elevated radials and if you take 
even one to the ground you might as well move all to the ground..??Fred KB4QZH 
 Original message From: donov...@erols.com Date: 12/29/20  
12:30 PM  (GMT-05:00) To: topband@contesting.com Subject: Re: Topband: Elevated 
Radials - will radials on ground help? Hi Clive, A second resonant radial is a 
good idea, but not because it might cancel horizontally polarized radiation. 
Why? Because -- just like a Beverage -- a horizontal wire close to the ground 
has no significant horizontally polarized radiation. Essentially all of the 
horizontally polarized radiation is lost to ground losses. 73 Frank W3LPL - 
Original Message -From: cl...@gm3poi.com To: donov...@erols.com, 
topband@contesting.com Sent: Tuesday, December 29, 2020 5:25:05 PM Subject: RE: 
Topband: Elevated Radials - will radials on ground help? Frank what about 
adding another radial to each vertical to cancel the Horizontal polarisation 
from the single radial. 73 Clive GM3POI -Original Message- From: 
Topband  On Behalf Of 
donov...@erols.com Sent: 29 December 2020 17:01 To: topband@contesting.com 
Subject: Re: Topband: Elevated Radials - will radials on ground help? Hi Dan, 
Your small lot is an ideal candidate for K2AV's folded counterpoise. Contact 
K2AV for guidance, he's helped countless successful users. www.k2av.com A few 
clarifications regarding radials and gain: Radials have absolutely nothing to 
do with gain. They only reduce ground losses within a fraction of a wavelength 
of the antenna. The realistic opportunities to further reduce losses are: - 
install the antenna on salt march like K3ZM and W1KM, or - install the antenna 
closer than one mile to sea water in the foreground of the antenna for at least 
a few miles in the most important directions. But you've already done that. 
Bravo! Good luck! 73 Frank W3LPL - Original Message - From: "Dan Flaig 
NP2J"  To: donov...@erols.com Sent: Tuesday, December 29, 2020 
4:41:40 PM Subject: Re: Topband: Elevated Radials - will radials on ground 
help? On 2020-12-29 10:06, donov...@erols.com wrote: > Hi Dan, > > An 
inverted-L with one elevated radial has lots of room for > improvement, > 
almost anything will improve what you now have. > > How much improvement you 
can achieve is mostly determined by site > limitations, copper wire expense, 
how much work you're able do > yourself or pay someone else to do for you. > > 
Eight radials, 70 feet long is the absolute minimum number of radials > if you 
lay them on the ground. Sixteen 80-foot radials will be much > better, > 32 
100-radials will be significantly better than that. Finally 60 > 125-foot > 
radials will be within one dB of the best you could achieve. > > This is the 
classic reference: > > ncjweb.com/bonus-content/k3lcmaxgainradials.pdf > > If 
you continue to use resonant elevated radials, four is the minimum > number 
your should shoot for, but unfortunately its difficult to get > all > four 
elevated radials to carry similar amounts of current. Eight > elevated > 
radials is much better. > > The K2AV Folded counterpoise is another alternative 
to your > current single elevated radial. > > Good luck! > > 73 > Frank > W3LPL 
> > - > > From: d...@np2j.com > To: 
topband@contesting.com > Sent: Tuesday, December 29, 2020 1:58:53 PM > Subject: 
Topband: Elevated Radials - will radials on ground help? > > Hello fellow 
Topbanders! > > Had lots of fun in the Stew, thanks for the contacts everyone! 
> > Looking forward to the CQ160 and as always trying to find a way to > 
improve antenna performance so looking for advice > > I am currently using 
a pair of Inverted L's each having a single > elevated radial. > The 
feedpoint's and elevated radials are 10-12 feet above ground. > The soil is 
fairly rocky. > Also quite a bit of "Bush" growing fairly high except below 
elevated > radials where I have trimmed back the bush. > > I am wondering if I 
should lay radials on the ground, particulary near > > the feedpoint's? > Any 
advice?? > > 73 > Dan K8RF/NP2J > _ > Searchable Archives: 
http://www.contesting.com/_topband - Topband > Reflector Frank, Thanks for the 
reply. My lot is narrow and runs North to South. The elevated radials run 
towards the North, figured might have small amount of gain in that direction. I 
could maybe add one or two additional elevated radials but they would be only 
angled a few degrees plus or minus from the current single radial going North. 
I am on side of ahill at abt 300 feet elevation about 3/4 of a mile from the 
North shoreline. 73 Dan _ Searchable Archives: 
http://www.contesting.com/_topband - Topband Reflector 
_Searchable Archives: http://www.contesting.com/_topband - 
Topband Reflector
_
Searchable Archives: http://www.contesting.com/_topband - Topband Reflector

Re: Topband: Elevated Radials - will radials on ground help?

[Jim Brown]

On 12/29/2020 5:58 AM, d...@np2j.com wrote:
I am wondering if I should lay radials on the ground, particulary near 
the feedpoint's?

Any advice??


In addition to what Frank has written, I suggest that you study this 
link for ideas.


http://k9yc.com/160MPacificon.pdf

FWIW, I heard you pretty solidly every time I tuned the band for an S 
run during the Stew from my QTH near San Francisco, and your signal was 
roughly comparable to NP2X.


My specific suggestions are to 1) add more elevated radials; 2) try to 
elevate them to 16-20 ft; 3) try to make them equal length 4) try to 
make them longer; 5) alternatively, use a LOT of on-ground radials, 
length and quantity are roughly equivalent -- that is, more is better.


73, Jim K9YC
_
Searchable Archives: http://www.contesting.com/_topband - Topband Reflector

Re: Topband: Elevated Radials - will radials on ground help?

[donovanf]

Hi Clive, 


A second resonant radial is a good idea, but not because it might 
cancel horizontally polarized radiation. 


Why? 


Because -- just like a Beverage -- a horizontal wire close to the ground 
has no significant horizontally polarized radiation. Essentially all 
of the horizontally polarized radiation is lost to ground losses. 


73 
Frank 
W3LPL 

- Original Message -

From: cl...@gm3poi.com 
To: donov...@erols.com, topband@contesting.com 
Sent: Tuesday, December 29, 2020 5:25:05 PM 
Subject: RE: Topband: Elevated Radials - will radials on ground help? 

Frank what about adding another radial to each vertical to cancel the 
Horizontal polarisation from the single radial. 73 Clive GM3POI 

-Original Message- 
From: Topband  On Behalf Of 
donov...@erols.com 
Sent: 29 December 2020 17:01 
To: topband@contesting.com 
Subject: Re: Topband: Elevated Radials - will radials on ground help? 

Hi Dan, 


Your small lot is an ideal candidate for K2AV's folded counterpoise. 
Contact K2AV for guidance, he's helped countless successful users. 


www.k2av.com 


A few clarifications regarding radials and gain: 


Radials have absolutely nothing to do with gain. They only reduce ground 
losses within a fraction of a wavelength of the antenna. 


The realistic opportunities to further reduce losses are: 


- install the antenna on salt march like K3ZM and W1KM, or 


- install the antenna closer than one mile to sea water in the 
foreground of the antenna for at least a few miles in the most 
important directions. But you've already done that. Bravo! 

Good luck! 


73 
Frank 
W3LPL 



- Original Message - 

From: "Dan Flaig NP2J"  
To: donov...@erols.com 
Sent: Tuesday, December 29, 2020 4:41:40 PM 
Subject: Re: Topband: Elevated Radials - will radials on ground help? 

On 2020-12-29 10:06, donov...@erols.com wrote: 
> Hi Dan, 
> 
> An inverted-L with one elevated radial has lots of room for 
> improvement, 
> almost anything will improve what you now have. 
> 
> How much improvement you can achieve is mostly determined by site 
> limitations, copper wire expense, how much work you're able do 
> yourself or pay someone else to do for you. 
> 
> Eight radials, 70 feet long is the absolute minimum number of radials 
> if you lay them on the ground. Sixteen 80-foot radials will be much 
> better, 
> 32 100-radials will be significantly better than that. Finally 60 
> 125-foot 
> radials will be within one dB of the best you could achieve. 
> 
> This is the classic reference: 
> 
> ncjweb.com/bonus-content/k3lcmaxgainradials.pdf 
> 
> If you continue to use resonant elevated radials, four is the minimum 
> number your should shoot for, but unfortunately its difficult to get 
> all 
> four elevated radials to carry similar amounts of current. Eight 
> elevated 
> radials is much better. 
> 
> The K2AV Folded counterpoise is another alternative to your 
> current single elevated radial. 
> 
> Good luck! 
> 
> 73 
> Frank 
> W3LPL 
> 
> - 
> 
> From: d...@np2j.com 
> To: topband@contesting.com 
> Sent: Tuesday, December 29, 2020 1:58:53 PM 
> Subject: Topband: Elevated Radials - will radials on ground help? 
> 
> Hello fellow Topbanders! 
> 
> Had lots of fun in the Stew, thanks for the contacts everyone! 
> 
> Looking forward to the CQ160 and as always trying to find a way to 
> improve antenna performance so looking for advice 
> 
> I am currently using a pair of Inverted L's each having a single 
> elevated radial. 
> The feedpoint's and elevated radials are 10-12 feet above ground. 
> The soil is fairly rocky. 
> Also quite a bit of "Bush" growing fairly high except below elevated 
> radials where I have trimmed back the bush. 
> 
> I am wondering if I should lay radials on the ground, particulary near 
> 
> the feedpoint's? 
> Any advice?? 
> 
> 73 
> Dan K8RF/NP2J 
> _ 
> Searchable Archives: http://www.contesting.com/_topband - Topband 
> Reflector 
Frank, 
Thanks for the reply. 
My lot is narrow and runs North to South. 
The elevated radials run towards the North, figured might have small 
amount of gain in that direction. 
I could maybe add one or two additional elevated radials but they would 
be only angled a few degrees plus or minus from the current single 
radial going North. 
I am on side of ahill at abt 300 feet elevation about 3/4 of a mile 
from the North shoreline. 

73 
Dan 

_ 
Searchable Archives: http://www.contesting.com/_topband - Topband Reflector 


_
Searchable Archives: http://www.contesting.com/_topband - Topband Reflector

Re: Topband: Elevated Radials - will radials on ground help?

[clive]

Frank what about adding another radial to each vertical to cancel the
Horizontal polarisation from the single radial.  73 Clive GM3POI

-Original Message-
From: Topband  On Behalf Of
donov...@erols.com
Sent: 29 December 2020 17:01
To: topband@contesting.com
Subject: Re: Topband: Elevated Radials - will radials on ground help?

Hi Dan, 


Your small lot is an ideal candidate for K2AV's folded counterpoise. 
Contact K2AV for guidance, he's helped countless successful users. 


www.k2av.com 


A few clarifications regarding radials and gain: 


Radials have absolutely nothing to do with gain. They only reduce ground
losses within a fraction of a wavelength of the antenna. 


The realistic opportunities to further reduce losses are: 


- install the antenna on salt march like K3ZM and W1KM, or 


- install the antenna closer than one mile to sea water in the 
foreground of the antenna for at least a few miles in the most 
important directions. But you've already done that. Bravo! 

Good luck! 


73 
Frank 
W3LPL 



- Original Message -

From: "Dan Flaig NP2J"  
To: donov...@erols.com 
Sent: Tuesday, December 29, 2020 4:41:40 PM 
Subject: Re: Topband: Elevated Radials - will radials on ground help? 

On 2020-12-29 10:06, donov...@erols.com wrote: 
> Hi Dan, 
> 
> An inverted-L with one elevated radial has lots of room for 
> improvement, 
> almost anything will improve what you now have. 
> 
> How much improvement you can achieve is mostly determined by site 
> limitations, copper wire expense, how much work you're able do 
> yourself or pay someone else to do for you. 
> 
> Eight radials, 70 feet long is the absolute minimum number of radials 
> if you lay them on the ground. Sixteen 80-foot radials will be much 
> better, 
> 32 100-radials will be significantly better than that. Finally 60 
> 125-foot 
> radials will be within one dB of the best you could achieve. 
> 
> This is the classic reference: 
> 
> ncjweb.com/bonus-content/k3lcmaxgainradials.pdf 
> 
> If you continue to use resonant elevated radials, four is the minimum 
> number your should shoot for, but unfortunately its difficult to get 
> all 
> four elevated radials to carry similar amounts of current. Eight 
> elevated 
> radials is much better. 
> 
> The K2AV Folded counterpoise is another alternative to your 
> current single elevated radial. 
> 
> Good luck! 
> 
> 73 
> Frank 
> W3LPL 
> 
> - 
> 
> From: d...@np2j.com 
> To: topband@contesting.com 
> Sent: Tuesday, December 29, 2020 1:58:53 PM 
> Subject: Topband: Elevated Radials - will radials on ground help? 
> 
> Hello fellow Topbanders! 
> 
> Had lots of fun in the Stew, thanks for the contacts everyone! 
> 
> Looking forward to the CQ160 and as always trying to find a way to 
> improve antenna performance so looking for advice 
> 
> I am currently using a pair of Inverted L's each having a single 
> elevated radial. 
> The feedpoint's and elevated radials are 10-12 feet above ground. 
> The soil is fairly rocky. 
> Also quite a bit of "Bush" growing fairly high except below elevated 
> radials where I have trimmed back the bush. 
> 
> I am wondering if I should lay radials on the ground, particulary near 
> 
> the feedpoint's? 
> Any advice?? 
> 
> 73 
> Dan K8RF/NP2J 
> _ 
> Searchable Archives: http://www.contesting.com/_topband - Topband 
> Reflector 
Frank, 
Thanks for the reply. 
My lot is narrow and runs North to South. 
The elevated radials run towards the North, figured might have small 
amount of gain in that direction. 
I could maybe add one or two additional elevated radials but they would 
be only angled a few degrees plus or minus from the current single 
radial going North. 
I am on side of ahill at abt 300 feet elevation about 3/4 of a mile 
from the North shoreline. 

73 
Dan 

_
Searchable Archives: http://www.contesting.com/_topband - Topband Reflector

_
Searchable Archives: http://www.contesting.com/_topband - Topband Reflector

Re: Topband: Elevated Radials - will radials on ground help?

[donovanf]

Hi Dan, 


Your small lot is an ideal candidate for K2AV's folded counterpoise. 
Contact K2AV for guidance, he's helped countless successful users. 


www.k2av.com 


A few clarifications regarding radials and gain: 


Radials have absolutely nothing to do with gain. They only reduce 
ground losses within a fraction of a wavelength of the antenna. 


The realistic opportunities to further reduce losses are: 


- install the antenna on salt march like K3ZM and W1KM, or 


- install the antenna closer than one mile to sea water in the 
foreground of the antenna for at least a few miles in the most 
important directions. But you've already done that. Bravo! 

Good luck! 


73 
Frank 
W3LPL 



- Original Message -

From: "Dan Flaig NP2J"  
To: donov...@erols.com 
Sent: Tuesday, December 29, 2020 4:41:40 PM 
Subject: Re: Topband: Elevated Radials - will radials on ground help? 

On 2020-12-29 10:06, donov...@erols.com wrote: 
> Hi Dan, 
> 
> An inverted-L with one elevated radial has lots of room for 
> improvement, 
> almost anything will improve what you now have. 
> 
> How much improvement you can achieve is mostly determined by site 
> limitations, copper wire expense, how much work you're able do 
> yourself or pay someone else to do for you. 
> 
> Eight radials, 70 feet long is the absolute minimum number of radials 
> if you lay them on the ground. Sixteen 80-foot radials will be much 
> better, 
> 32 100-radials will be significantly better than that. Finally 60 
> 125-foot 
> radials will be within one dB of the best you could achieve. 
> 
> This is the classic reference: 
> 
> ncjweb.com/bonus-content/k3lcmaxgainradials.pdf 
> 
> If you continue to use resonant elevated radials, four is the minimum 
> number your should shoot for, but unfortunately its difficult to get 
> all 
> four elevated radials to carry similar amounts of current. Eight 
> elevated 
> radials is much better. 
> 
> The K2AV Folded counterpoise is another alternative to your 
> current single elevated radial. 
> 
> Good luck! 
> 
> 73 
> Frank 
> W3LPL 
> 
> - 
> 
> From: d...@np2j.com 
> To: topband@contesting.com 
> Sent: Tuesday, December 29, 2020 1:58:53 PM 
> Subject: Topband: Elevated Radials - will radials on ground help? 
> 
> Hello fellow Topbanders! 
> 
> Had lots of fun in the Stew, thanks for the contacts everyone! 
> 
> Looking forward to the CQ160 and as always trying to find a way to 
> improve antenna performance so looking for advice 
> 
> I am currently using a pair of Inverted L's each having a single 
> elevated radial. 
> The feedpoint's and elevated radials are 10-12 feet above ground. 
> The soil is fairly rocky. 
> Also quite a bit of "Bush" growing fairly high except below elevated 
> radials where I have trimmed back the bush. 
> 
> I am wondering if I should lay radials on the ground, particulary near 
> 
> the feedpoint's? 
> Any advice?? 
> 
> 73 
> Dan K8RF/NP2J 
> _ 
> Searchable Archives: http://www.contesting.com/_topband - Topband 
> Reflector 
Frank, 
Thanks for the reply. 
My lot is narrow and runs North to South. 
The elevated radials run towards the North, figured might have small 
amount of gain in that direction. 
I could maybe add one or two additional elevated radials but they would 
be only angled a few degrees plus or minus from the current single 
radial going North. 
I am on side of ahill at abt 300 feet elevation about 3/4 of a mile 
from the North shoreline. 

73 
Dan 

_
Searchable Archives: http://www.contesting.com/_topband - Topband Reflector

Re: Topband: Elevated Radials - will radials on ground help?

[donovanf]

Hi Dan, 


An inverted-L with one elevated radial has lots of room for improvement, 
almost anything will improve what you now have. 


How much improvement you can achieve is mostly determined by site 
limitations, copper wire expense, how much work you're able do 
yourself or pay someone else to do for you. 


Eight radials, 70 feet long is the absolute minimum number of radials 
if you lay them on the ground. Sixteen 80-foot radials will be much better, 
32 100-radials will be significantly better than that. Finally 60 125-foot 
radials will be within one dB of the best you could achieve. 


This is the classic reference: 


ncjweb.com/bonus-content/k3lcmaxgainradials.pdf 


If you continue to use resonant elevated radials, four is the minimum 
number your should shoot for, but unfortunately its difficult to get all 
four elevated radials to carry similar amounts of current. Eight elevated 
radials is much better. 


The K2AV Folded counterpoise is another alternative to your 
current single elevated radial. 


Good luck! 


73 
Frank 
W3LPL 








- Original Message -

From: d...@np2j.com 
To: topband@contesting.com 
Sent: Tuesday, December 29, 2020 1:58:53 PM 
Subject: Topband: Elevated Radials - will radials on ground help? 

Hello fellow Topbanders! 

Had lots of fun in the Stew, thanks for the contacts everyone! 

Looking forward to the CQ160 and as always trying to find a way to 
improve antenna performance so looking for advice 

I am currently using a pair of Inverted L's each having a single 
elevated radial. 
The feedpoint's and elevated radials are 10-12 feet above ground. 
The soil is fairly rocky. 
Also quite a bit of "Bush" growing fairly high except below elevated 
radials where I have trimmed back the bush. 

I am wondering if I should lay radials on the ground, particulary near 
the feedpoint's? 
Any advice?? 

73 
Dan K8RF/NP2J 
_ 
Searchable Archives: http://www.contesting.com/_topband - Topband Reflector 

_
Searchable Archives: http://www.contesting.com/_topband - Topband Reflector

Re: Topband: elevated radials

[Grant Saviers]

Agree, an array is an entirely different ball game.  Thanks.

Grant KZ1w

On 10/22/2018 8:47 AM, John Kaufmann wrote:

When you are using just a single vertical, some pattern skew is probably 
acceptable.  However, at KC1XX we are using several verticals in an array and 
nonideal radiation from the individual verticals degrades the directive pattern 
that we are trying to achieve.

73, John W1FV

-Original Message-
From: Grant Saviers [mailto:gran...@pacbell.net]
Sent: Monday, October 22, 2018 11:38 AM
To: jkaufm...@alum.mit.edu; Topband@contesting.com
Subject: Re: Topband: elevated radials

I have a 160m T with 8 elevated 125' radials and the currents are worst
case 3:1 unequal for various reasons (nearby steel building & towers).
I've modeled this with EZNEC Pro4 by placing the actual radial currents
as sources in each radial.  Obviously the sum of those currents must
equal the vertical current and those measurements agree.

I'm wondering what is your "radials generate unwanted radiation".  The
modeling shows the pattern is less than 1 db "out of round" with my
unbalanced currents.

I know there are many comments that radial currents must be equalized.
My own DXpedition experience with single radial SteppIR CrankIRs and
modeling them shows only a 2 or 3 of db "out of round".Some other
modeling I did showed small pattern skew even with 3 or 4 radials removed.

So what am I missing?

Grant KZ1W

On 10/21/2018 15:22 PM, John Kaufmann wrote:

We just went through the exercise of tuning up the elevated radials on the
KC1XX 160m vertical array in advance of the upcoming CQWW DX Contests.

The first thing is to make each of the radials look as electrically
identical as possible.  We assume the length of the vertical element is
fixed and not adjustable.  We start by connecting one radial at a time to
the feedpoint of the vertical and measuring the impedance at the vertical
feedpoint.  In general the impedances will not be exactly the same.  With
unequal impedances, the currents flowing in each of the radials will
generally be unequal, which is undesirable because then the radials generate
unwanted radiation.   Suppressing that radiation depends on making the
radial currents as close to equal as possible so that in the far field, the
radiation from each radial is cancelled by the out-of-phase radiation from
an opposing radial.  The lengths of each of the radials then need to be
adjusted to equalize the feedpoint impedances of the vertical with one
radial at a time.

We trimmed the radial lengths to make the feedpoint reactance X=0 at the
desired resonant frequency of the vertical.  (Note that if there are other
vertical elements present in an array, they have to be detuned to insure
they do not corrupt the measurement.)  However when we did this, we found
that the resistance (R) at the feedpoint was different with each individual
radial and it was not possible to equalize the resistances and reactances
simultaneously.   Apparently this is because of the non-homogeneous
environment (ground and surrounding trees) around each radial.  So, we do
the best we can in equalizing the impedances and accept some degree of
imperfection.  The more radials present around the vertical, the more
forgiving the system is of imperfections in radial symmetry.

As a final check we then connect all of the radials to the vertical element
and check the impedance again.  The resonance (where the reactance X=0)
should be close to the resonance that was obtained in the radial trimming
exercise for the vertical with one radial at a time.

73, John W1FV

_
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_
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_
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Re: Topband: elevated radials

[John Kaufmann]

When you are using just a single vertical, some pattern skew is probably 
acceptable.  However, at KC1XX we are using several verticals in an array and 
nonideal radiation from the individual verticals degrades the directive pattern 
that we are trying to achieve.

73, John W1FV

-Original Message-
From: Grant Saviers [mailto:gran...@pacbell.net] 
Sent: Monday, October 22, 2018 11:38 AM
To: jkaufm...@alum.mit.edu; Topband@contesting.com
Subject: Re: Topband: elevated radials

I have a 160m T with 8 elevated 125' radials and the currents are worst 
case 3:1 unequal for various reasons (nearby steel building & towers).  
I've modeled this with EZNEC Pro4 by placing the actual radial currents 
as sources in each radial.  Obviously the sum of those currents must 
equal the vertical current and those measurements agree.

I'm wondering what is your "radials generate unwanted radiation".  The 
modeling shows the pattern is less than 1 db "out of round" with my 
unbalanced currents.

I know there are many comments that radial currents must be equalized.  
My own DXpedition experience with single radial SteppIR CrankIRs and 
modeling them shows only a 2 or 3 of db "out of round".Some other 
modeling I did showed small pattern skew even with 3 or 4 radials removed.

So what am I missing?

Grant KZ1W

On 10/21/2018 15:22 PM, John Kaufmann wrote:
> We just went through the exercise of tuning up the elevated radials on the
> KC1XX 160m vertical array in advance of the upcoming CQWW DX Contests.
>
> The first thing is to make each of the radials look as electrically
> identical as possible.  We assume the length of the vertical element is
> fixed and not adjustable.  We start by connecting one radial at a time to
> the feedpoint of the vertical and measuring the impedance at the vertical
> feedpoint.  In general the impedances will not be exactly the same.  With
> unequal impedances, the currents flowing in each of the radials will
> generally be unequal, which is undesirable because then the radials generate
> unwanted radiation.   Suppressing that radiation depends on making the
> radial currents as close to equal as possible so that in the far field, the
> radiation from each radial is cancelled by the out-of-phase radiation from
> an opposing radial.  The lengths of each of the radials then need to be
> adjusted to equalize the feedpoint impedances of the vertical with one
> radial at a time.
>
> We trimmed the radial lengths to make the feedpoint reactance X=0 at the
> desired resonant frequency of the vertical.  (Note that if there are other
> vertical elements present in an array, they have to be detuned to insure
> they do not corrupt the measurement.)  However when we did this, we found
> that the resistance (R) at the feedpoint was different with each individual
> radial and it was not possible to equalize the resistances and reactances
> simultaneously.   Apparently this is because of the non-homogeneous
> environment (ground and surrounding trees) around each radial.  So, we do
> the best we can in equalizing the impedances and accept some degree of
> imperfection.  The more radials present around the vertical, the more
> forgiving the system is of imperfections in radial symmetry.
>
> As a final check we then connect all of the radials to the vertical element
> and check the impedance again.  The resonance (where the reactance X=0)
> should be close to the resonance that was obtained in the radial trimming
> exercise for the vertical with one radial at a time.
>
> 73, John W1FV
>
> _
> Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
>

_
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Re: Topband: elevated radials

[Grant Saviers]

I have a 160m T with 8 elevated 125' radials and the currents are worst 
case 3:1 unequal for various reasons (nearby steel building & towers).  
I've modeled this with EZNEC Pro4 by placing the actual radial currents 
as sources in each radial.  Obviously the sum of those currents must 
equal the vertical current and those measurements agree.


I'm wondering what is your "radials generate unwanted radiation".  The 
modeling shows the pattern is less than 1 db "out of round" with my 
unbalanced currents.


I know there are many comments that radial currents must be equalized.  
My own DXpedition experience with single radial SteppIR CrankIRs and 
modeling them shows only a 2 or 3 of db "out of round".    Some other 
modeling I did showed small pattern skew even with 3 or 4 radials removed.


So what am I missing?

Grant KZ1W

On 10/21/2018 15:22 PM, John Kaufmann wrote:

We just went through the exercise of tuning up the elevated radials on the
KC1XX 160m vertical array in advance of the upcoming CQWW DX Contests.

The first thing is to make each of the radials look as electrically
identical as possible.  We assume the length of the vertical element is
fixed and not adjustable.  We start by connecting one radial at a time to
the feedpoint of the vertical and measuring the impedance at the vertical
feedpoint.  In general the impedances will not be exactly the same.  With
unequal impedances, the currents flowing in each of the radials will
generally be unequal, which is undesirable because then the radials generate
unwanted radiation.   Suppressing that radiation depends on making the
radial currents as close to equal as possible so that in the far field, the
radiation from each radial is cancelled by the out-of-phase radiation from
an opposing radial.  The lengths of each of the radials then need to be
adjusted to equalize the feedpoint impedances of the vertical with one
radial at a time.

We trimmed the radial lengths to make the feedpoint reactance X=0 at the
desired resonant frequency of the vertical.  (Note that if there are other
vertical elements present in an array, they have to be detuned to insure
they do not corrupt the measurement.)  However when we did this, we found
that the resistance (R) at the feedpoint was different with each individual
radial and it was not possible to equalize the resistances and reactances
simultaneously.   Apparently this is because of the non-homogeneous
environment (ground and surrounding trees) around each radial.  So, we do
the best we can in equalizing the impedances and accept some degree of
imperfection.  The more radials present around the vertical, the more
forgiving the system is of imperfections in radial symmetry.

As a final check we then connect all of the radials to the vertical element
and check the impedance again.  The resonance (where the reactance X=0)
should be close to the resonance that was obtained in the radial trimming
exercise for the vertical with one radial at a time.

73, John W1FV

_
Searchable Archives: http://www.contesting.com/_topband - Topband Reflector


_
Searchable Archives: http://www.contesting.com/_topband - Topband Reflector

Re: Topband: elevated radials

[Mike Waters]

Hi Pete,

*Ideally*, the current on each radial should be equal. In the searchable
archives at http://www.contesting.com/_topband this has been discussed at
length, and in a number of threads. There are also instructions there for
making a very simple RF current meter with only two or three components, so
you can measure the RF current in each radial.

Having said that, I modeled my inverted-L with only ONE radial. The pattern
was not near as bad as one might think! (Somewhere, I think I still have
the EZNEC .ez file. The problem might be figuring which computer it's on.
It may be on my website somewhere. ;-)

My 160m inverted-L had just two 10' high radials. I was so eager to get on
160 that I never even bothered to measure the current. :-)

On my ground radials webpage at
www.w0btu.com/Optimum_number_of_ground_radials_vs_radial_length.html ,
there are some links to articles by experts that discuss elevated radials.
Scroll down past the graphics. (Please excuse the unfinished mess, the
photos should be on the same page, but they are not.)

See also www.w0btu.com/160_meters.html for photos etc. of my antenna.

Hope this helps.

73, Mike
www.w0btu.com

On Sat, Oct 20, 2018 at 8:45 PM N4ZR  wrote:

> I am contemplating 4 elevated radials for a 160-meter inverted L.  Am I
> correct to think that I need to resonate each pair of radials in their
> final location as if they were a very low dipole?
> 73, Pete N4ZR
>
_
Searchable Archives: http://www.contesting.com/_topband - Topband Reflector

Re: Topband: elevated radials

[John Kaufmann]

We just went through the exercise of tuning up the elevated radials on the
KC1XX 160m vertical array in advance of the upcoming CQWW DX Contests.

The first thing is to make each of the radials look as electrically
identical as possible.  We assume the length of the vertical element is
fixed and not adjustable.  We start by connecting one radial at a time to
the feedpoint of the vertical and measuring the impedance at the vertical
feedpoint.  In general the impedances will not be exactly the same.  With
unequal impedances, the currents flowing in each of the radials will
generally be unequal, which is undesirable because then the radials generate
unwanted radiation.   Suppressing that radiation depends on making the
radial currents as close to equal as possible so that in the far field, the
radiation from each radial is cancelled by the out-of-phase radiation from
an opposing radial.  The lengths of each of the radials then need to be
adjusted to equalize the feedpoint impedances of the vertical with one
radial at a time.

We trimmed the radial lengths to make the feedpoint reactance X=0 at the
desired resonant frequency of the vertical.  (Note that if there are other
vertical elements present in an array, they have to be detuned to insure
they do not corrupt the measurement.)  However when we did this, we found
that the resistance (R) at the feedpoint was different with each individual
radial and it was not possible to equalize the resistances and reactances
simultaneously.   Apparently this is because of the non-homogeneous
environment (ground and surrounding trees) around each radial.  So, we do
the best we can in equalizing the impedances and accept some degree of
imperfection.  The more radials present around the vertical, the more
forgiving the system is of imperfections in radial symmetry.  

As a final check we then connect all of the radials to the vertical element
and check the impedance again.  The resonance (where the reactance X=0)
should be close to the resonance that was obtained in the radial trimming
exercise for the vertical with one radial at a time.  

73, John W1FV

_
Searchable Archives: http://www.contesting.com/_topband - Topband Reflector

Re: Topband: elevated radials

[Mike Furrey]

I took a page out of ON4UN's book for four elevated radials. In the 4th edition 
of his "Low-Band DXing," page 9-25, figure 9-23, I used the left diagram. After 
I resonated the system, my best SWR was about 2.5 and I fixed that by adding a 
"hair pin" match. The length of my radials was 81' and were up about 15'. This 
worked quite well for me.

Unfortunately that antenna is in a box since I am currently (temporarily) in a 
house on a 1/5 acre lot with an 1/8 wavelength wire vertical to a tree limb and 
a single 1/8 wavelength elevated radial. Ugh. BUT I am on the air. Just can't 
hear in this very old neighborhood until I get some kind of RX antenna built.
73, Mike WA5POK




On Saturday, October 20, 2018 9:45 PM, N4ZR  wrote:
 

 I am contemplating 4 elevated radials for a 160-meter inverted L.  Am I 
correct to think that I need to resonate each pair of radials in their 
final location as if they were a very low dipole?

-- 

73, Pete N4ZR
Check out the Reverse Beacon Network
at , now
spotting RTTY activity worldwide.
For spots, please use your favorite
"retail" DX cluster.

_
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_
Searchable Archives: http://www.contesting.com/_topband - Topband Reflector

Re: Topband: elevated radials

[Roy Koeppe]

I do recall reading old books that advised elevated radials should be 
resonated slightly lower in frequency than the main element. Anyone else 
recall such?


73,   Roy K6XK


"I am contemplating 4 elevated radials for a 160-meter inverted L.  Am I
correct to think that I need to resonate each pair of radials in their
final location as if they were a very low dipole?"


73, Pete N4ZR


_
Searchable Archives: http://www.contesting.com/_topband - Topband Reflector

Re: Topband: elevated radials

[Chuck Dietz]

That worked for me.

Chuck W5PR

On Sat, Oct 20, 2018 at 8:45 PM N4ZR  wrote:

> I am contemplating 4 elevated radials for a 160-meter inverted L.  Am I
> correct to think that I need to resonate each pair of radials in their
> final location as if they were a very low dipole?
>
> --
>
> 73, Pete N4ZR
> Check out the Reverse Beacon Network
> at , now
> spotting RTTY activity worldwide.
> For spots, please use your favorite
> "retail" DX cluster.
>
> _
> Searchable Archives: http://www.contesting.com/_topband - Topband
> Reflector
>
_
Searchable Archives: http://www.contesting.com/_topband - Topband Reflector

Re: Topband: elevated radials

[Carl]

I would expect that after X number of elevated radials it becomes moot. 
Height and ground conductivity determine the actual number.


For my poor ground and 20' elevation it was somewhere around 24 based upon 
the antenna analyzer. Since all were run over branches and a lot of dead 
wood falls around here in the winter I went to 32 to have a few extra.


Carl
KM1H
- Original Message - 
From: Mike Waters mikew...@gmail.com

To: topband topband@contesting.com
Sent: Friday, September 20, 2013 11:42 AM
Subject: Re: Topband: elevated radials



Hello Jim,

Thank you for this. I don't doubt for a second that my elevated 1/4 wave
radial currents may be unequal. I should throw together an RF current 
meter

and check them sometime, and add more radials while I'm at it. After the
ticks and chiggers here die, though. :-)

I don't have any Communications Quarterly issues, but K5IU's article 
sounds

interesting, if anyone has a copy.

73, Mike
www.w0btu.com

**

Hey Mike

Saw your post to TB reflector:

I suppose if you made the elevated radials long, then you could adjust
the current balance with series variable capacitors. You could use a 
simple

clamp-on meter like W8JI has on his site to measure the relative current,
perhaps.I didn't bother with that myself, I was just careful to keep the
radial lengths the same length and height.

My old friend K5IU had an article Optimum Elevated Radial Vertical
Antennas in Communication Quarterly, Spring 1997, pp 9 - 27.  He showed
why 1/4 wave elevated radials are the worst length as it invariably 
results

in radials having unequal currents (at least on the low bands where the
height is small in terms of lambda).  He only concluded the pattern was
distorted, explicitly stating no opinion on efficiency.  Dick is pretty
careful - he likes actual measurements. The fix was to use non-1/4 wave
radials with a single lumped reactance between the shield and the 
junction
of all the radials to bring to resonance.  Using separate reactors for 
each

radial makes it too critical to adjust.

Since some of his measurements showed next to no current in some radials,
I figured right off the efficiency would almost always be higher with 
equal

currents, even when using shorter radials of the same number.  I never
needed to use elevated radials, so it was all merely academic for me.

I'll bet anything you have very unequal currents in your elevated radials
despite their being precisely the same physical length.  Dick's article
shows how he measured the currents with a simple HB device.  Don't know 
if

it is simpler than W8JI's or not.


_
Topband Reflector


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Topband Reflector

Re: Topband: elevated radials

[Mike Waters]

Hello Jim,

Thank you for this. I don't doubt for a second that my elevated 1/4 wave
radial currents may be unequal. I should throw together an RF current meter
and check them sometime, and add more radials while I'm at it. After the
ticks and chiggers here die, though. :-)

I don't have any Communications Quarterly issues, but K5IU's article sounds
interesting, if anyone has a copy.

73, Mike
www.w0btu.com

**
 Hey Mike

 Saw your post to TB reflector:

 I suppose if you made the elevated radials long, then you could adjust
 the current balance with series variable capacitors. You could use a simple
 clamp-on meter like W8JI has on his site to measure the relative current,
 perhaps.I didn't bother with that myself, I was just careful to keep the
 radial lengths the same length and height.

 My old friend K5IU had an article Optimum Elevated Radial Vertical
 Antennas in Communication Quarterly, Spring 1997, pp 9 - 27.  He showed
 why 1/4 wave elevated radials are the worst length as it invariably results
 in radials having unequal currents (at least on the low bands where the
 height is small in terms of lambda).  He only concluded the pattern was
 distorted, explicitly stating no opinion on efficiency.  Dick is pretty
 careful - he likes actual measurements. The fix was to use non-1/4 wave
 radials with a single lumped reactance between the shield and the junction
 of all the radials to bring to resonance.  Using separate reactors for each
 radial makes it too critical to adjust.

 Since some of his measurements showed next to no current in some radials,
 I figured right off the efficiency would almost always be higher with equal
 currents, even when using shorter radials of the same number.  I never
 needed to use elevated radials, so it was all merely academic for me.

 I'll bet anything you have very unequal currents in your elevated radials
 despite their being precisely the same physical length.  Dick's article
 shows how he measured the currents with a simple HB device.  Don't know if
 it is simpler than W8JI's or not.

_
Topband Reflector

Re: Topband: elevated radials

[Mike Waters]

Thanks, Doug.

On Fri, Sep 20, 2013 at 10:53 AM, Doug Scribner
dscrib...@myfairpoint.netwrote:

 Mike,

 My emails to the reflector keep getting bounced back. Post this if you'd
 like...

 Here's a fairly extensive study by Rudy, N6LF...

 In the article (38 pages), he acknowledges K5IU for his assistance.

 http://rudys.typepad.com/**files/elevated-ground-systems-**
 article-final-version.pdfhttp://rudys.typepad.com/files/elevated-ground-systems-article-final-version.pdf

 Doug - K1ZO

 - Original Message - From: Mike Waters mikew...@gmail.com
 To: topband topband@contesting.com
 Sent: Friday, September 20, 2013 11:42 AM
 Subject: Re: Topband: elevated radials


  Hello Jim,

 Thank you for this. I don't doubt for a second that my elevated 1/4 wave
 radial currents may be unequal. I should throw together an RF current
 meter


_
Topband Reflector

Re: Topband: elevated radials

[Charlie Cunningham]

Hi, Mike

You've reminded me that I have pair of 2 amp FS RF ammeters (1950s/1960s
era) that I need to hunt up and squirrel away before clearing out the junk
around my home and preparing to move out. Someday, I may be able to put up
another 160 antenna!

73,
Charlie, K4OTV

-Original Message-
From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of Mike
Waters
Sent: Friday, September 20, 2013 11:42 AM
To: topband
Subject: Re: Topband: elevated radials

Hello Jim,

Thank you for this. I don't doubt for a second that my elevated 1/4 wave
radial currents may be unequal. I should throw together an RF current meter
and check them sometime, and add more radials while I'm at it. After the
ticks and chiggers here die, though. :-)

I don't have any Communications Quarterly issues, but K5IU's article sounds
interesting, if anyone has a copy.

73, Mike
www.w0btu.com

**
 Hey Mike

 Saw your post to TB reflector:

 I suppose if you made the elevated radials long, then you could adjust
 the current balance with series variable capacitors. You could use a
simple
 clamp-on meter like W8JI has on his site to measure the relative current,
 perhaps.I didn't bother with that myself, I was just careful to keep the
 radial lengths the same length and height.

 My old friend K5IU had an article Optimum Elevated Radial Vertical
 Antennas in Communication Quarterly, Spring 1997, pp 9 - 27.  He showed
 why 1/4 wave elevated radials are the worst length as it invariably
results
 in radials having unequal currents (at least on the low bands where the
 height is small in terms of lambda).  He only concluded the pattern was
 distorted, explicitly stating no opinion on efficiency.  Dick is pretty
 careful - he likes actual measurements. The fix was to use non-1/4 wave
 radials with a single lumped reactance between the shield and the junction
 of all the radials to bring to resonance.  Using separate reactors for
each
 radial makes it too critical to adjust.

 Since some of his measurements showed next to no current in some radials,
 I figured right off the efficiency would almost always be higher with
equal
 currents, even when using shorter radials of the same number.  I never
 needed to use elevated radials, so it was all merely academic for me.

 I'll bet anything you have very unequal currents in your elevated radials
 despite their being precisely the same physical length.  Dick's article
 shows how he measured the currents with a simple HB device.  Don't know if
 it is simpler than W8JI's or not.

_
Topband Reflector

_
Topband Reflector

Re: Topband: Elevated Radials EPILOGUE

[ZR]

ON4UN's series of books have always had way too many individual assumptions 
and we all know what happens then.


Those books offer a place to start and then apply your own unique soil and 
local conditions and change as needed.


Carl
KM1H

- Original Message - 
From: Buck wh7dx wh...@hawaii.rr.com

To: topband@contesting.com
Sent: Wednesday, March 06, 2013 3:42 PM
Subject: Re: Topband: Elevated Radials EPILOGUE


There is some good stuff in ON4UN Low Band Book -  Chapter 9-10 on 
Elevated Radials.


He suggests that an elevated system would be even better above ground 
versus on the ground in poor conditions.   References 0.1 wave height or 
less.   For 160m that could be 50 feet down.   In Section 2.2.7 K3LC says 
that there is no point in raising radials any higher than 6 meters on 160 
or 3 meters on 80 meters.  Such a height would be between 0.2db of what 
can be achieved with 64 buried radials...  N7CL says they need to be 
higher


The perfect on ground system might be 50-100 1/4 wave ground radials...

In 2.1.2 he warns of trusting modeling because of outside factors.

9-12 Figure 9-18 (modeling) regarding 160m gain using 1/4 wave is 
interesting over average ground.  If you wanted max. it suggests using 
120 - 80meter radials.   But the difference between 120 (1.5 dbi gain) and 
going with 32 (1.0 dbi gain) would make one wonder if it was really worth 
it for another 1-2 miles of wire.. work?   0.5 dbi gain?


The Conclusion in 9-14 is interesting..  basically saying..

Take the example of an 80-meter vertical over average ground: going from 
a lousy eight 20-meter long radials to 120 radials would only buy you 
1.4db of gain, which is less than what I think it is in reality.  In very 
good ground that difference wold be only 0.7 db!


2.1.3.2 - From these almost 70-year old studies, we can conclude that 60 
quarter-wave long radials is a cost effective optimal solution for amateur 
purposes.


K3NA's work in 2.3.1.3 talks about using 1/16 wave radials.. not going 
beyond 48.. but that doesn't match up with N6BV's work several years 
prior.


In 2.2 Elevated Radial and beyond it's gets really interesting and less 
conclusive?


The Conclusion States - If you want to play it extra safe, and if you 
have the tower height, get the radials up as high as possible and add a 
few more.   Use a ground screen if you have it.


It all is very logical.  Get away from the lossy ground or hide the lossy 
ground with a dense screen using many radials.  No free lunch!.


This was one book and it goes on.

All of this sounds like a great episode for Ham Radio Myth Busters...

73,

Bryan
WH7DX







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Re: Topband: Elevated Radials - Inverted L, Near Fld above/below ground

[Dan Maguire]

One poster on this thread mentioned a desire to compare an inverted L with 
elevated radials against a quarter-wave vertical with elevated radials.  
Another poster mentioned looking at the near field below the surface.

I put together a .weq format model for use with the AutoEZ program, with all 
dimensions controlled by variables.  Here's a general view:

http://ac6la.com/adhoc/ElevRadInvL.gif

You can use this one model to study what happens when you change the height of 
the radials, the length of the radials, the length of the vertical section, 
and/or the length of the horizontal section.  The horizontal section length may 
be set to zero in which case the model becomes a simple vertical.  In the view 
above the radials are 130 ft (~87 deg), the vertical section is an arbitrary 65 
ft, and the horizontal section has been automatically set to ~71.9 ft which 
produces resonance at the feedpoint.  Test frequency is 1.832 MHz.

Here's the model file:

http://ac6la.com/adhoc/ElevRadInvL.weq

If you want to play with this model using the free AutoEZ Demo program you'll 
have to adjust the segmentation density down to roughly 20 segments per WL from 
the current 100 segs per WL.

Finally, mostly just out of curiosity, here's what the near field looks like at 
1 ft above ground.  This is looking straight down on the antenna.  The color 
scale represents E-fld intensity.

http://ac6la.com/adhoc/InvLNFat+1.gif

And here's the E-fld at 1 ft *below* ground.  This is not an apples-to-apples 
comparison; note the range of the scale is greatly reduced.  (NEC4 engine 
required to produce this view.)

http://ac6la.com/adhoc/InvLNFat-1.gif

AutoEZ (http://ac6la.com/autoez.html) works in conjunction with EZNEC v. 5.  If 
you prefer to use the free 4nec2 program it would be fairly simple to create an 
equivalent model using 4nec2 SY cards.  

Dan, AC6LA
http://ac6la.com/
_
Topband Reflector

Re: Topband: Elevated Radials

[Pete Smith N4ZR]

The other rule that seems to apply, based on a number of pretty serious 
articles, including K3LC's NCJ series in the mid-2000s,is they that 
has, gets.  By which I mean, if you have good ground conductivity, a 
relatively sparse radial field can work better than a really extensive 
radial field on lousy ground.


73, Pete N4ZR
Check out the Reverse Beacon Network at
http://reversebeacon.net,
blog at reversebeacon.blogspot.com.
For spots, please go to your favorite
ARC V6 or VE7CC DX cluster node.

On 3/6/2013 11:54 AM, ZR wrote:
Since the radial field for any height vertical has equal importance 
the only way to get 1/4 wave efficiency is to have zero RF loss in the 
loading coil and matching network. Cryogenics anyone?


There is no magic wire minimalist radial or counterpoise that 
accomplishes that. All they provide is some improvement over a poor on 
ground radial attempt; I wont call it a radial system.


Carl
KM1H



- Original Message - From: Rick Karlquist 
rich...@karlquist.com

To: topband@contesting.com
Sent: Tuesday, March 05, 2013 8:42 PM
Subject: Re: Topband: Elevated Radials



One of the problems with discussing this topic is that
nearly all studies of radials deal with 1/4 wave verticals.
Most ham stations including mine don't have the luxury of
a height of 130 feet.

There are many cases where some novel grounding scheme
is touted as just as good as 120 radials and indeed it
may be for the 1/4 wave height case.

What is scarce is advice for the owner of a short vertical
as to what to do about grounding.  What grounding scheme
would it take to make the proverbial 43 foot vertical play
as good as a 130 foot vertical?  Whatever that scheme is,
we know that it will have very narrow bandwidth.  This is
a good litmus test to separate short vertical installations
worthy of additional testing from low efficiency ones.  Of course, 
narrow

bandwidth is merely necessary, but not sufficient, to
prove high efficiency.  The advantage of the bandwidth
criterion is that it is easily and unambiguously measured,
as opposed to field strength.  The bandwidth should ideally
be determined by measuring the antenna drive impedance
directly, rather than looking at it through a matching
network.  A matching network will to a greater or lesser
extent decrease the bandwidth of the antenna.  Alternately,
the matching network can be modeled to remove its effect
on bandwidth.

I think it is less likely that you can be fooled by a bandwidth
measurement than you can with base impedance measurements.


Rick
N6RK



_
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Topband Reflector

Re: Topband: Elevated Radials

[Tom W8JI]

I've noted your postings re elevated radials to replace deteriorated 
buried

radial fields  under broadcast towers. I'm familiar with the work and the
results. This work, of course was done by professional broadcast engineers
with significant instrumentation at their disposal. Of course, they also 
had

to measure the field intensity in the far field and file it with the FCC.
Their work seemed to show that, once we have installed 4 elevated 1/4 wave
radials we're reaching the point of diminishing returns and that little 
is

to be gained by increasing the number of radials beyond 4.



Charlie,

We shouldn't be critical of people. People believe what they want to 
believe, including you and all of us. Here is how it really works:


1.) In an FCC measurement, a test signal is sent and the SLOPE of 
attenuation in the far field is used to estimate earth conductivity.


2.) A graph (or formula, but generally a graph) based on the measured 
attenuation slope is used to predict the expected signal at standard 
distances.


This creates a problem, because if we look at measurements along a line in 
any direction, they are often all over the place at various points. The 
engineer has to smooth the readings out and match a curve, which gives the 
engineer considerable lattitude depending on how he does the smoothing.


Even more important, ONE measurement system over one ground that contains 
multiple old radials of unknown condition and one set of soil conditions 
does not mean it applies to other conditions.


By far, the most accurate way to determine a change is to do a direct 
measurement of what we want to know in an A-B comparison with only the 
variable we are trying to define changed. This takes out the human emotional 
factors and other errors, and then rememmber it applies to that case.


No matter how much we want something to be true, or how much we like or 
agree with something, this is just how it **really** works. It's human 
nature to gravitate toward a system that takes little room and installation 
time, doesn't cost much, and is an it always works this way silver bullet.


We should not pick at people and call people names who point out obvious 
flaws and limitations in faith-based conclusions. Anyone who has objectively 
made measurements realizes there is no single universal answer, no matter 
how nice it would be if there actually was one.


73 Tom 


_
Topband Reflector

Re: Topband: Elevated Radials

[Richard Fry]

RE:  Capability of NEC for Accurate Modeling of Groundwave Fields Close to a 
Monopole using Elevated Radials


As an example...

The FCC groundwave propagation chart for 1490 kHz (Graph 18-A) shows that 
the field at 1 km over 1 mS/m earth is 51% of the inverse distance field.


The inverse distance field is the field existing for a perfect ground plane. 
The reduction for real earth paths is due to propagation loss over less than 
perfect earth.


Going back to my NEC model of a 1/4-wave monopole driven against 4 x 
1/4-wave elevated radials, I changed the ground type from perfect to a 
conductivity of 1 mS/m.  The NEC-calculated field at a distance of 1 km for 
1 kW of applied power dropped from 313 mV/m to 160 mV/m, which is a 
reduction to 51% of the field for a perfect ground plane.


NEC is quite capable of giving us the correct answer, when it is asked the 
right question. 


_
Topband Reflector

Re: Topband: Elevated Radials

[john battin]

This reminds me of an experience I had with a new antenna.  After working 
several days installing a new antenna, I attached it to an a/b switch to 
compare it with my old antenna. I was delighted, the new antenna was always 
better !!!  Then to my dismay I saw I had the switrch reversed ... oh boy... I 
changed the feeds, and continued the test.  Guess what.. the new antenna was 
still always better. 
Lesson learned  human nature and switching antennas in face of QSB.
 
John K9DX 


 From: w...@w8ji.com
 To: topband@contesting.com
 Date: Wed, 6 Mar 2013 08:00:56 -0500
 Subject: Re: Topband: Elevated Radials
 
  I've noted your postings re elevated radials to replace deteriorated 
  buried
  radial fields under broadcast towers. I'm familiar with the work and the
  results. This work, of course was done by professional broadcast engineers
  with significant instrumentation at their disposal. Of course, they also 
  had
  to measure the field intensity in the far field and file it with the FCC.
  Their work seemed to show that, once we have installed 4 elevated 1/4 wave
  radials we're reaching the point of diminishing returns and that little 
  is
  to be gained by increasing the number of radials beyond 4.
 
 
 Charlie,
 
 We shouldn't be critical of people. People believe what they want to 
 believe, including you and all of us. Here is how it really works:
 
 1.) In an FCC measurement, a test signal is sent and the SLOPE of 
 attenuation in the far field is used to estimate earth conductivity.
 
 2.) A graph (or formula, but generally a graph) based on the measured 
 attenuation slope is used to predict the expected signal at standard 
 distances.
 
 This creates a problem, because if we look at measurements along a line in 
 any direction, they are often all over the place at various points. The 
 engineer has to smooth the readings out and match a curve, which gives the 
 engineer considerable lattitude depending on how he does the smoothing.
 
 Even more important, ONE measurement system over one ground that contains 
 multiple old radials of unknown condition and one set of soil conditions 
 does not mean it applies to other conditions.
 
 By far, the most accurate way to determine a change is to do a direct 
 measurement of what we want to know in an A-B comparison with only the 
 variable we are trying to define changed. This takes out the human emotional 
 factors and other errors, and then rememmber it applies to that case.
 
 No matter how much we want something to be true, or how much we like or 
 agree with something, this is just how it **really** works. It's human 
 nature to gravitate toward a system that takes little room and installation 
 time, doesn't cost much, and is an it always works this way silver bullet.
 
 We should not pick at people and call people names who point out obvious 
 flaws and limitations in faith-based conclusions. Anyone who has objectively 
 made measurements realizes there is no single universal answer, no matter 
 how nice it would be if there actually was one.
 
 73 Tom 
 
 _
 Topband Reflector
  
_
Topband Reflector

Re: Topband: Elevated Radials

[ZR]

Since the radial field for any height vertical has equal importance the only 
way to get 1/4 wave efficiency is to have zero RF loss in the loading coil 
and matching network. Cryogenics anyone?


There is no magic wire minimalist radial or counterpoise that accomplishes 
that. All they provide is some improvement over a poor on ground radial 
attempt; I wont call it a radial system.


Carl
KM1H



- Original Message - 
From: Rick Karlquist rich...@karlquist.com

To: topband@contesting.com
Sent: Tuesday, March 05, 2013 8:42 PM
Subject: Re: Topband: Elevated Radials



One of the problems with discussing this topic is that
nearly all studies of radials deal with 1/4 wave verticals.
Most ham stations including mine don't have the luxury of
a height of 130 feet.

There are many cases where some novel grounding scheme
is touted as just as good as 120 radials and indeed it
may be for the 1/4 wave height case.

What is scarce is advice for the owner of a short vertical
as to what to do about grounding.  What grounding scheme
would it take to make the proverbial 43 foot vertical play
as good as a 130 foot vertical?  Whatever that scheme is,
we know that it will have very narrow bandwidth.  This is
a good litmus test to separate short vertical installations
worthy of additional testing from low efficiency ones.  Of course, narrow
bandwidth is merely necessary, but not sufficient, to
prove high efficiency.  The advantage of the bandwidth
criterion is that it is easily and unambiguously measured,
as opposed to field strength.  The bandwidth should ideally
be determined by measuring the antenna drive impedance
directly, rather than looking at it through a matching
network.  A matching network will to a greater or lesser
extent decrease the bandwidth of the antenna.  Alternately,
the matching network can be modeled to remove its effect
on bandwidth.

I think it is less likely that you can be fooled by a bandwidth
measurement than you can with base impedance measurements.


Rick
N6RK



_
Topband Reflector


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Topband Reflector

Re: Topband: Elevated Radials EPILOGUE

[Buck wh7dx]

Now in the most recent 22nd Edition of the ARRL Antenna Book...

3-14 - It goes on to say that a few elevated radials should perform as well as 
a large number of ground radials

And that the signal will improve quickly with just a little elevation...  
Interesting graph - Figure 3.27  - you need to get to about 30 ground radials 
to equal 4 elevated.

The elevated needed to be symmetric...

It goes on from there.

I suspect the fairly recent (??) information on the advantages of elevated has 
let to at least one military study and a ton of other information on the 
internet... talk about reconditioned AM stations with elevated radial?

Buried is safer - but it requires a lot more work and money.   But if you can 
use 8 (???) elevated radials versus 60 buried on 160M we're talking a mile 
difference in wire. 

Don't get me wrong, I'm new to this and by no means knowledgeable in the field 
- but I can say that after reading these two very well know books.. and a ton 
of stuff on the Internet - which is my specialty.. It's a little confusing..

It's time for Myth Busters Ham Radio.   It should be fairly simple I would 
think..  Poor ground - (X) number of elevated at a specified wave length height 
- symmetrically laid out...   Decent ground - (X) ground or (X) elevated at 
this wave length height.. etc

That should do it for me.

If anyone has more real life info on this..   email me at my call sign + 
@hawaii.rr.com

73

Bryan
WH7DX







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Topband Reflector

Re: Topband: Elevated Radials EPILOGUE

[The Bucks]

I'd like to read whatever information (real results) you guys have on this.   
My email is my call sign with  @hawaii.rr.com

Thank you Milt for your info.   Nice setup!If I understood it correctly - 
the buried and elevated were comparable.  

I've read most of the well known books on this and it's not conclusive.. after 
all these years - I would expect it be more certain.

I don't think the data is getting out there perhaps or I haven't seen it.A 
study done working with low band grounding etc...

Things like

1) If you have the space and work hours and money isn't an issue - go with 120 
1/4 wave buried radials.

2) Good soil doesn't require as many radials..   someone was commenting on the 
AM towers be reconditioned - using elevated radials.   

3) Elevated radials work better with poor ground conditions.   Higher with 
lower bands.. 15-25ft on 160m..

4) You don't need as many elevated radials as ground radial..  (debate about 4 
to 12 or so?)   I'd say 12 but would like to see a study.   Some say 2 or 4? 

Once you have the control antenna it's easy to start comparing real world 
results.How's 12 radials sound?Cut 4 off..   how's 8 sounds. The 
K.I.S.S.  approach.

I don't think it would be very hard to disconnect some radials and say - how's 
the signal now?...  two guys with a walkie talkie making doing some tests 
cutting some wires etc... 

During the 160M SSB there was a guy in CA who was 59 the whole time into 
Hawaii.   I called him back on the last day and asked what he was using..  I 
forgot what he said, but he switched his antennas and he went from a solid S9 
to S5.   He said that sounds about right.That was a huge difference.   

I was using a 160m dipole up about 30ft at the center and 10 feet on the ends.  
I'm sure that wouldn't model very well but I was 56 to him.   I do need to 
model in my sloping terrain to ocean etc..

That poorly modeled dipole that would be shooting up 90 degrees or something 
can go 5000+ miles.


That's what I'm talking about.Why bother with a ton of wires and work 
unless you can see a real world difference. I'm putting in an inverted L 
with the FCP ground to see how that compares to my low dipole (radials are hard 
for me)

My results will be based on - Jack (W2XX), let me switch my antenna and tell 
me how you copy me.If it's not a noticeable difference I might want use 
that extra coax connection for something else later.

$.02



[CONFIDENTIALITY AND PRIVACY NOTICE] Information transmitted by this email is 
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population, which isn't our concern. If you are not the intended lucky 
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proper authority of the Wizard of Email or Al Gore, you are notified that any 
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_
Topband Reflector

Re: Topband: Elevated Radials

[Guy Olinger K2AV]

Pretty picture for perfect ground, but no dice in real life.

The very same NEC 4.2 with raised quarter wave radials over routine real
life ground made of dirt will show field intensities in the ground.  Since
there is a field in the ground, and the ground is conductive with a
resistance there will be current and I squared R losses.  The fields
immediately underneath the radials will be different than in the areas that
bisect the radials.  This difference increases with poorer earth.

This loss MUST be subtracted from the power fed to the antenna.

All one has to do to examine this is to run near field tables with negative
elevations. Squaring the field values and summing them up is a way to
evaluate and understand changes in ground loss with changes in radials.

73, Guy.

On Tue, Mar 5, 2013 at 5:56 AM, Richard Fry r...@adams.net wrote:

 Developing this topic a little more, the link below shows a NEC4.2 model of
 a 1/4-wave, vertical monopole driven against a set of 4 x 1/4-wave
 horizontal wires used as an elevated counterpoise.  The base of the
 monopole
 and the elevation of the radial wires are set to 4.9 meters, as in the
 Culpepper system I posted earlier in this thread (Sat, 2 March 2013 at
 04.33:34 -0600).  The relative amplitudes and phases are shown for each
 conductor. Frequency is 1490 kHz.  The system was modeled over perfect
 earth.

 This system produces an inverse distance groundwave field of ~313 mV/m at
 1 km for 1 kW of applied power.  This is the maximum theoretical field
 possible for those conditions for a perfect, series-fed, 1/4-wave monopole
 base-driven against a perfect ground plane.

 The azimuth radiation pattern is perfectly circular.  This is as expected,
 because the only conductor producing useful far-field radiation is the
 vertical monopole, itself.  There is no physical reason why that radiation
 should be other than omnidirectional, at all elevation angles.

 But while the performance shown by this NEC model is identical to that of a
 perfect monopole with its base attached to a perfect, flat ground plane of
 infinite extent, none of the r-f current flowing on the vertical section
 has
 needed to flow through the earth to reach the monopole.  In fact, the NEC
 model HAS no structural connection to the earth !

 No earth currents will flow along the vertical monopole in such elevated
 systems even when they are installed just above a non-perfect ground plane,
 such as the earth.

 This illustrates how such an elevated system using only 4 x 1/4-wave
 horizontal wires as a counterpoise can equal the performance of a
 conventional 1/4-wave monopole using as many as 120 x 1/2-wave radials
 buried in real earth.

 http://i62.photobucket.com/**albums/h85/rfry-100/**
 Culpepper1_zps566188da.jpghttp://i62.photobucket.com/albums/h85/rfry-100/Culpepper1_zps566188da.jpg

 RF

 _
 Topband Reflector

_
Topband Reflector

Re: Topband: Elevated Radials

[Richard Fry]

Guy Olinger posted:
...The very same NEC 4.2 with raised quarter wave radials over routine real 
life ground made of dirt will show field intensities in the ground. (etc 
etc)

___

Sorry, but this is a misunderstanding/misuse of NEC for this situation.

The r-f currents flowing in the earth under and near elevated, horizontal 
radials are NOT the source for the r-f currents flowing on those radials, 
themselves.  Those radial wire currents are supplied by the currents flowing 
on the inside surface of the outer conductor of a coaxial transmission line 
used to drive the monopole -- which is connected to the common point of 
those elevated radial wires.


Elevated radials behave much differently than buried radials.  In effect, 
driving a vertical monopole against an even number of geometrically- 
symmetric pairs of at least two elevated, horizontal wires used as a 
counterpoise converts a base fed (unbalanced) monopole radiator into a 
balanced radiator -- which neither needs, nor can use a structural 
connection to the earth for most efficient system performance.


For proof of this, please study the measurements of a real-world system 
using 4 x 1/4-wave elevated radials described in the link below, for/at 
WPCI, 1490 kHz in Greenville, SC, and the rest of that paper.


http://www.commtechrf.com/documents/nab1995.pdf

RF 


_
Topband Reflector

Re: Topband: Elevated Radials

[Rick Karlquist]

One of the problems with discussing this topic is that
nearly all studies of radials deal with 1/4 wave verticals.
Most ham stations including mine don't have the luxury of
a height of 130 feet.

There are many cases where some novel grounding scheme
is touted as just as good as 120 radials and indeed it
may be for the 1/4 wave height case.

What is scarce is advice for the owner of a short vertical
as to what to do about grounding.  What grounding scheme
would it take to make the proverbial 43 foot vertical play
as good as a 130 foot vertical?  Whatever that scheme is,
we know that it will have very narrow bandwidth.  This is
a good litmus test to separate short vertical installations
worthy of additional testing from low efficiency ones.  Of course, narrow
bandwidth is merely necessary, but not sufficient, to
prove high efficiency.  The advantage of the bandwidth
criterion is that it is easily and unambiguously measured,
as opposed to field strength.  The bandwidth should ideally
be determined by measuring the antenna drive impedance
directly, rather than looking at it through a matching
network.  A matching network will to a greater or lesser
extent decrease the bandwidth of the antenna.  Alternately,
the matching network can be modeled to remove its effect
on bandwidth.

I think it is less likely that you can be fooled by a bandwidth
measurement than you can with base impedance measurements.


Rick
N6RK



_
Topband Reflector

Re: Topband: Elevated Radials EPILOGUE

[Tom W8JI]

1) If you have the space and work hours and money isn't an issue - go with 
120 1/4 wave buried radials.




That is a myth that stems from the FCC not requiring a ground system proof 
of performance when more than ~110 radials are used, and 120 radials is 
pretty much a waste of time for hams. At my location on 40 meters, somewhere 
about 15 radials got on the flat part of efficiency curve and on 160 about 
30-40 radials gets really flat for changes.


The only reason I have 100 radials on my 200 ft tower is I had the wire, I 
have a radial plow, I wanted lightning protection, and I used to hang 
horizontal antennas in that area so I wanted a counterpoise under them.


2) Good soil doesn't require as many radials..   someone was commenting on 
the AM towers be reconditioned - using elevated radials.




That isn't a good rule. There are two cases of zero loss, perfect 
conductivity and no conductivity at all. Someplace between the two, loss 
will peak.


I have a mixture of soil from swampy rich soil to red clay. My 40 meter 
vertical test was over a patch of red rocky clay, and it only needed ~15 
radials to get on the flat part of the curve.


3) Elevated radials work better with poor ground conditions.   Higher with 
lower bands.. 15-25ft on 160m..




That's not a good rule, or at least it is not a rule that has been 
substantiated.


4) You don't need as many elevated radials as ground radial..  (debate 
about 4 to 12 or so?)   I'd say 12 but would like to see a study.   Some 
say 2 or 4?




Some, like N6LF, say 16 to be safe.

Once you have the control antenna it's easy to start comparing real world 
results.How's 12 radials sound?Cut 4 off..   how's 8 sounds. 
The K.I.S.S.  approach.


I don't think it would be very hard to disconnect some radials and say - 
how's the signal now?...  two guys with a walkie talkie making doing 
some tests cutting some wires etc...


You would have to actually remove the radials to see the full effect. The 
best way is to start with empty soil and work upwards, not cut things.


An A-B test comparison to a stable reference would be simple and reliable.

73 Tom 


_
Topband Reflector

Re: Topband: Elevated Radials

[Charlie Cunningham]

Hi. Richard

I've been following this thread -mostly for entertainment.

I've noted your postings re elevated radials to replace deteriorated buried
radial fields  under broadcast towers. I'm familiar with the work and the
results. This work, of course was done by professional broadcast engineers
with significant instrumentation at their disposal. Of course, they also had
to measure the field intensity in the far field and file it with the FCC.
Their work seemed to show that, once we have installed 4 elevated 1/4 wave
radials we're reaching the point of diminishing returns and that little is
to be gained by increasing the number of radials beyond 4.

I'm sure  you appreciate by now that there are a  LOT of authoritative and
fervently held opinions that are spouted in this reflector without any
supporting data or results. And we can't reason people out of positions
that they didn't arrive at through reason!!  Most hams do not seem to
appreciate that a 160m inverted -L with elevated 1/4 wave resonant radials
is, in fact, a ground-plane antenna, with the vertical radiator bent to make
use of available supports and should be considered and analyzed as such!
Nevertheless, there are a LOT of authoritative pronouncements like as many
as possible (elevated radials) or as high as possible (again for elevated
radials - and this only serves to reduce the effective height of the
high-current portion of the vertical radiator). Hams seem more inclined to
rely on apocrypha, and hearsay from folks that they consider to be
authoritative topband gurus.  These views, though passionately and
fervently held, generally are lacking of supporting data, and theoretical
support. They are entertaining, but not really helpful!

There seems to be something mysterious and sacred in the topband
community about dirt! About the only rationale that I can arrive at for
buried radials is if one is shunt feeding a grounded tower. If the vertical
radiator can be isolated from ground, then the elevated resonant radials
will do very  nicely.

I ran 160m inverted Ls with resonant elevated radials for  years - usually 3
or 4, but sometimes just two, and a couple of them had to  be bent because
of lot limitations. With 500-600W I could be heard pretty much anywhere in
the world - VK6,3B8,ZL,ZS, KH6,.JA and deep Russians etc. from my lot in
NC.  My problem was never being heard- it was HEARING!(I helped the hearing
issue a LOT when I put in some Kaz terminated loops that could be
accommodated on my city lot.)  My radials were not very high 5-6 feet along
the property fence lies and one ran along under the eaves of my one-story
house because it was convenient. It all worked really well until Hurricane
Fran took down the tree that was supporting the far end of the inverted L
that was about 75 feet. Because of intervening  hip replacement surgery and
a long recovery I haven't rebuilt it -yet. But have hopes and plans for this
summer. 

Anyway, reasoning, or arguing, with topband hams about antennas is a lot
like having a religious or political discourse. Generally they seem to just
BELIEVE!

I do appreciate and value your posts on this reflector.

Best regards,
Charlie, K4OTV
Charles Cunningham  Jr,  PE

P.S. Elevated radial DO need to be high enough that we (or wildlife) don't r
un inti them



-Original Message-
From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of Richard
Fry
Sent: Tuesday, March 05, 2013 6:45 PM
To: topband@contesting.com
Subject: Re: Topband: Elevated Radials

Guy Olinger posted:
...The very same NEC 4.2 with raised quarter wave radials over routine real

life ground made of dirt will show field intensities in the ground. (etc 
etc)
___

Sorry, but this is a misunderstanding/misuse of NEC for this situation.

The r-f currents flowing in the earth under and near elevated, horizontal 
radials are NOT the source for the r-f currents flowing on those radials, 
themselves.  Those radial wire currents are supplied by the currents flowing

on the inside surface of the outer conductor of a coaxial transmission line 
used to drive the monopole -- which is connected to the common point of 
those elevated radial wires.

Elevated radials behave much differently than buried radials.  In effect, 
driving a vertical monopole against an even number of geometrically- 
symmetric pairs of at least two elevated, horizontal wires used as a 
counterpoise converts a base fed (unbalanced) monopole radiator into a 
balanced radiator -- which neither needs, nor can use a structural 
connection to the earth for most efficient system performance.

For proof of this, please study the measurements of a real-world system 
using 4 x 1/4-wave elevated radials described in the link below, for/at 
WPCI, 1490 kHz in Greenville, SC, and the rest of that paper.

http://www.commtechrf.com/documents/nab1995.pdf

RF 

_
Topband Reflector

_
Topband Reflector

Re: Topband: Elevated Radials EPILOGUE

[Tom W8JI]

I can't believe that no one has put this really important question to bed 
already.


Since the results vary with installation and soil, and since no one 
considers it depends a good answer, the debate will never end.



If I had the land and an existing vertical with a large buried radial 
system and another tower available.. I would try it out for the sake of 
Ham Radio :-))




I've already done that using field strength readings. I'm sure others have 
also.




P.S. Can someone with a tower also test out a low dipole around 30 ft and 
then go to 60, 90 and 120 and post the results.   I'm thinking a pulley 
and rope and some quick 10 minutes adjustments for real world results... 
that one's easy.




I already did that. I made thousands of A-B-C comparisons between high 
dipoles, low dipoles, and a reference vertical. For a period of time I even 
had two dipoles at 250 feet or so phased.


The problem is what works here for what I do can be considerably different 
than other places and what someone else wants.


VK3ZL also compared a shorter vertical with a ~100-foot high dipole for a 
long period of time. All of these tests were blind A-B tests.


The problem is results vary not only with the installation and location, but 
also with the distance, time of day, and solar conditions.


Bob and I both pretty much settled on verticals, as did ZL3REX and others.

Anyone who has made extensive A-B comparisons likely gets a chuckle out of 
I took down an antenna and put up another one and it was   difference 
statements. It takes a long time period of many direct A-B comparisons to 
reach dependable conclusions.


73 Tom 


_
Topband Reflector

Re: Topband: Elevated Radials EPILOGUE

[Wes Attaway (N5WA)]

Buck I think a lot of people have already done these kinds of tests.

Tom and others have given a pretty thorough run-down of the different
factors and results to expect.  And, it all mostly agrees with modeling.

There are a lot of real world differences such as type of ground, nearby
terrain levels, buildings, overhead wires, and so on.  Then, there are
economic factors.

About all you can do is to put up whatever you can live with at your locale.
Or, you could buy a perfect location somewhere and operate a remote station
via an internet link.


- Wes Attaway (N5WA) --- 
1138 Waters Edge Circle, Shreveport, LA 71106 
318-797-4972 (Office) - 318-393-3289 (Cell) 
Computer Consulting and Forensics 
-- EnCase Certified Examiner --- 

-Original Message-
From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of Buck
wh7dx
Sent: Sunday, March 03, 2013 12:39 PM
To: topband@contesting.com
Subject: Re: Topband: Elevated Radials EPILOGUE

I can't believe that no one has put this really important question to bed
already.

If I had the land and an existing vertical with a large buried radial system
and another tower available.. I would try it out for the sake of Ham Radio
:-))

Put up another 160M vertical..   contact a few friends from around North
America or International and take some notes.

Put 2  1/4 wave elevated radials up in the air.. 10ft.   Then try 30ft..
take some notes.   How did the control sample compare (buried radials).
Should give you an idea of propagation and changes.

Put 4  1/4 wave in the air..  (if you noticed a difference with 10ft and
30ft - don't bother with the weaker one)   any difference with 4 versus
2? - I'd bet there is...

Put 12  1/4 wave in the air...how does that compare?   Pretty close to
Control Sample??What are the real world results.   If it's one S unit
and I don't need to lay a mile-plus of wire buried in the ground.. that
might be enough.

I don't think people want to have a ton of elevated radials in the air
either - and I'm reading that you don't need to.

If you don't want to go with elevated - then bury as many in the ground as
you can - have fun... 

Surely, someone has the room and energy (friends) to give us all the final
answer to this question.   It would be a blast to do.   We'll all pitch in
some beer money.

Please post the results..   :-)


P.S. Can someone with a tower also test out a low dipole around 30 ft and
then go to 60, 90 and 120 and post the results.   I'm thinking a pulley and
rope and some quick 10 minutes adjustments for real world results...  that
one's easy.

Bryan
WH7DX


[CONFIDENTIALITY AND PRIVACY NOTICE] Information transmitted by this email
is proprietary to Mr.  Mrs. B and is intended for use only by the
individual or entity to which it is addressed, or where ever the hell it
ends up, and will almost certainly contain information that will offend a
large portion of the population, which isn't our concern. If you are not the
intended lucky recipient, or it appears that this mail has been forwarded to
you without the proper authority of the Wizard of Email or Al Gore, you are
notified that any thought, use, or consumption of this email is entirely
your choice. In such case, Bon AppetitNote:  A $.02 Internet Tax was
charged for receiving this email and all funds were given to some family
somewhere in America or the U.N  Have a nice day.

_
Topband Reflector

_
Topband Reflector

Re: Topband: Elevated Radials

[Wes Attaway (N5WA)]

When I first looked at Eddy's list I laughed.  

However, it does convey a clear message that there are a lot of ways to
achieve the goal of a workable low-band vertical.

I certainly won't argue with the quest for an answer to the what is best
question, but at some level almost every ham has to settle for the best that
they can reasonably do.

The K2AV FCP idea is really good for people who want to have a decent
antenna on 160 and where concealing all the wires along a backyard fence
line fits their idea of combining aesthetics with performance.  It is a
great idea but is probably not as good as a situation with 120 perfectly
spaced ground radials or 60 perfectly spaced elevated radials.

Tom, W8JI, and others can put up really great layouts in open fields but
this is not an option for many hams.  Thus, we get to the situation Eddy
reveals Do what you can reasonably do and don't worry about every
theoretical Db or fraction of a Db.

Personally, I don't want to walk out into my backyard and have to look at a
bunch of wires drooping all over the place.  That is why I like K2AV's
design.  Other people think differently.

So be it.  Put something up and get on the air.  A new country might show up
while you are fiddling with one more radial.


- Wes Attaway (N5WA) --- 
1138 Waters Edge Circle, Shreveport, LA 71106 
318-797-4972 (Office) - 318-393-3289 (Cell) 
Computer Consulting and Forensics 
-- EnCase Certified Examiner --- 

-Original Message-
From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of Eddy
Swynar
Sent: Saturday, March 02, 2013 7:48 AM
To: topband@contesting.com
Subject: Re: Topband: Elevated Radials

Good Day Again All,

Well, I've done my best to summarize all the respondents' comments in the
matter of elevated vs. ground-mounted radials---and I'll try now to
summarize these in a single-page format for benefit of all to see...

The results are certainly interesting, and some are as different from one
another as we might be physically! 

In any event---and FWIW---here goes:


(A) Is it true that a couple of elevated radials are just as effective as
the optimum amount of buried ones...?

-It depends.
-Don't know.
-Don't know.
-If 2 or more are used, maybe.
-It depends.


(B) What is the ideal number of elevated radials that one should use...?

-It depends upon their height.
-2.
-2 to 4.
-7 to 8.
-1 to 5.
-2.
-8.
-1 to 2.
-16 to 32.
-16 to 32.
-The more the better.
-Any amount, but use pairs (ex. 2 to 4, 6 to 8, etc.).


(C) How many elevated radials are just enough...?

-Enough to overcome ground losses  establish resonance.
-2.
-2
-2.
-2.
-4.
-4 (8 is overkill).
-1.
-32.
-8.
-Depends upon soil quality


(D) How high should these radials be...?

-The higher the better to clear pedestrians, animals, etc.
-10'.
-6' to 8'.-6' to 8'.
-12' to 14'.
-7' to 8'.
-6' to 15'.
-20'.
-6' to 10'.
-8'.
-10' to 12'.
-20'.
-1' to 10' (but the higher the better).


(E) Would it be a requirement that I raise the feedpoints of my L's to the
same height as the elevated radials, or can I simply leave the bases where
they are now (at ground level)  simply slant the radials upward with no
effect upon performance...?

-Gull wing arrangement OK.
-Feed point should be 8' high.
-Not sure.
-Makes no difference.
-Gull wing OK.
-Gull wing OK.
-Not sure.
-Same height as radials (to minimize ground loss).
-Makes no difference.
-Optional.


(F) Is it OK to bend the elevated radials to fit property allotments...?

-Slight bends OK.
-Yes.
-Yes.
-Yes.
-Not sure.
-Not sure.
-OK, but gradual bends only.
-No.
-Yes.
-Best kept straight.


(G) What is the desirable length of an elevated radial...?

-Quarter wave.
-Quarter wave.
-Quarter wave.
-Quarter wave.
-Quarter wave.
-Quarter wave.
-Quarter wave.
-Quarter wave.
-Quarter wave.
-Quarter wave.
-Use short radials with a common coil.
-Quarter wave + height above ground.


(H) Should any existing connections to real earth at the base of the L's
(i.e. a ground pipe) be completed severed with a system of elevated
radials...?

-If radials one quarter wave long, makes no difference.
-No ground.
-No ground.
-With a ground, there'll be noise on receive.
-NEVER ground.
-No ground.
-No ground.
-No ground.
-No ground.
-No ground.


Additionally, four respondents recommended using a choke balun at the
feedpoint...one person avowed that a single elevated radial was the
equivalent of 30 ground radials...another stated that 8 elevated radials
were super good, but that even 1 to 2 would be good...another affirms that
one simply can not beat the optimal number of buried radials...

Several recommended this site as an excellent reference as well:
http://www.antennasbyn6lf.com/2012/02/elevated-radial-ground-systems-some-ca
utions.html

I personally haven't taken a look at it myself here, but it is most
certainly on my to do list!

I hope my effort here might help dissipate some of the fog surrounding
elevated

Re: Topband: Elevated Radials

[Grant Saviers]

Tom,

Great stuff! Could you elaborate on a couple of points -

1. I would think that a system with elevated radials that slope upward 
towards the far ends (e.g for 160m 10' at feedpoint and 30' at far ends) 
should have less loss as the field is less near earth where the voltage 
is high in the radial. (unless there is something else that goes the 
wrong way).


2. Is 1/4 wl resonance at all important as the number of elevated 
radials increases - eg 10 total?  The QEX N6LF papers seem to indicate 
that a little less than 1/4 wl is optimum for that number of radials.


As much as I try to get answers to these from EZNEC+ the far field 
results are all the same, 4 or 10 elevated radials and sloping or not, 
resonant or not.


My VNWA shows my top loaded T for TB is right on but it doesn't seem 
to work as well as I expected. Perhaps at N48 deg latitude (Redmond, WA) 
one should not expect much for 160!


A suffering seven transplant,

Grant KZ1W

PS: if you have a moment please explain the pros and cons of skirt 
wires.  I think they are a good thing for top hat loading systems, but I 
can't reason it out for elevated or in the ground radials. The old VLF 
antennas all had them on the elevated ground planes, which isn't in any 
current recommended practice.


On 3/2/2013 4:55 AM, Tom W8JI wrote:


Forgive me, please, if I'm re-hashing a bit of the ...same-old, 
same-old here, but I am really curious as to any real world 
experiences that might be out there in the matter of elevated 
radials, vs. those that are simply laid atop the ground...


(A) Is it true that a couple of elevated radials are just as 
effective as the optimum amount of buried ones...?


Probably not a couple, but almost certainly in small systems a few 
elevated radials are better than the same number of buried radials.


Everyone would like this to be a cookie cutter answer, but the 
actual results depend heavily on the soil and installation. Even N6LF 
warns over and over that his data only applies for conditions like his.


(B) What is the ideal number of elevated radials that one should 
use...?


As many as you can. More never hurts the signal, it just is more work.


(C) How many elevated radials are just enough...?


It depends on the soil, the height, the antenna, and what you want.


(D) How high should these radials be...?


It depends on the antenna, soil, and installation. Radial height takes 
away from the effective antenna height. Certainly the safest thing is 
about .05 WL , unless the antenna is really short and that takes away 
significant radiator height.



(E) Would it be a requirement that I raise the feedpoints of my L's 
to the same height as the elevated radials, or can I simply leave the 
bases where they are now (at ground level)  simply slant the radials 
upward with no effect upon performance...?




It probably doesn't make much difference.



(F) Is it OK to bend the elevated radials to fit property allotments...?


It depends on where they are bent. The best practice is straight and 
symmetrical.




(G) What is the desirable length of an elevated radial...?


1/4 wave resonant length.

(H) Should any existing connections to real earth at the base of the 
L's (i.e. a ground pipe) be completed severed with a system of 
elevated radials...?


If the resonant radials are grounded to an earth ground, the system 
will lose efficiency. This much is always the case.


Pick the particular story you like Eddy, that's what most people do.  
:) Read the fine print though. N6LF, whose study is one of the most 
comprehensive is a good source for that particular test condition. 
Most people seem to miss this:


http://www.antennasbyn6lf.com/2012/02/elevated-radial-ground-systems-some-cautions.html 



What he writes isn't often what people actually paraphrase.

73 Tom
_
Topband Reflector



_
Topband Reflector

Re: Topband: Elevated Radials EPILOGUE

[Eddy Swynar]

Good Day All,

Well, after sifting through all of the responses to my original posting, and 
reviewing the different sites recommended by specific denizens of Topband, I've 
come to the conclusion that I will have to stick to my current design of 24 
radials, each 1/8-wave long, per L...

I believe that a minimum of two elevated radials would be the absolute minimum 
that I would have liked to try at my location---unfortunately, physical 
limitations of the property here would allow extended radials (i.e. going off 
in opposite directions to one another) beneath just one element in my 3-element 
array: the other 2 elements would benefit from a fully extended ( elevated, of 
course) single radial only, with the other twin being meandered about the 
property lines of the real estate that is available here...

While this arrangement might prove to be an effective compromise of 
sorts---compared to the questionable system that I currently employ---I don't 
know that I'd want to commit next year's Topband DX season to an arrangement 
that might be grossly inferior to what I now have, as tempting as any elevated 
set-up might be...and the current ground system has carried me through some 7 
years of reasonably reliable  faithful service to date...

So---bad knees notwithstanding!---I guess I'll have to stick to the tried  
true here,  hope that the propagation gods might render me better assistance 
next season, than they have this year.

Thanks again for all of the input that I received from everyone...

~73!~ de Eddy VE3CUI - VE3XZ
_
Topband Reflector

Re: Topband: Elevated Radials EPILOGUE

[Buck wh7dx]

I can't believe that no one has put this really important question to bed 
already.

If I had the land and an existing vertical with a large buried radial system 
and another tower available.. I would try it out for the sake of Ham Radio :-))

Put up another 160M vertical..   contact a few friends from around North 
America or International and take some notes.

Put 2  1/4 wave elevated radials up in the air.. 10ft.   Then try 30ft..  take 
some notes.   How did the control sample compare (buried radials).   Should 
give you an idea of propagation and changes.

Put 4  1/4 wave in the air..  (if you noticed a difference with 10ft and 30ft - 
don't bother with the weaker one)   any difference with 4 versus 2? - I'd 
bet there is...

Put 12  1/4 wave in the air...how does that compare?   Pretty close to 
Control Sample??What are the real world results.   If it's one S unit and 
I don't need to lay a mile-plus of wire buried in the ground.. that might be 
enough.

I don't think people want to have a ton of elevated radials in the air either - 
and I'm reading that you don't need to.

If you don't want to go with elevated - then bury as many in the ground as you 
can - have fun... 

Surely, someone has the room and energy (friends) to give us all the final 
answer to this question.   It would be a blast to do.   We'll all pitch in some 
beer money.

Please post the results..   :-)


P.S. Can someone with a tower also test out a low dipole around 30 ft and then 
go to 60, 90 and 120 and post the results.   I'm thinking a pulley and rope and 
some quick 10 minutes adjustments for real world results...  that one's easy.

Bryan
WH7DX


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_
Topband Reflector

Re: Topband: Elevated Radials

[Richard Fry]

(C) How many elevated radials are just enough...?



Depends on how many dB you want to throw away.  If you can, do 12 to

16. 32 is the kill-the-loss, never-look-back number.


The link below leads to a detailed post on this topic by William Culpepper, 
a broadcast consulting engineer.


Here is a relevant quote from W. Culppeper's post:

The result was an RMS value of the eight radials of 302.7 mV/m/kW at one
kilometer.  This compares with the FCC Figure 8 value of 307.8 mV/m/kW for a
93 degree tower with 120 ninety degree buried radials, however, a tower 87.2
degrees (the height of the WPCI tower above the four horizontal radials) has
an FCC rated efficiency of 303.7 mV/m/kW, one mV/m more than our measured
value.

The system using four elevated radials produced an accurately measured field 
that was 0.029 dB below the FCC theoretical field for the height of the 
monopole above the elevated radials.  Not much performance thrown away, 
there!


http://lists.contesting.com/archives//html/Topband/2007-11/msg00248.html

RF 


_
Topband Reflector

Re: Topband: Elevated Radials

[Eddy Swynar]

Good Day All,

Wow...!

I received well over TWENTY responses from the Topband crowd in the matter of 
elevated radials vs. those simply laid atop the ground---many thanks to all for 
sharing your insight  personal experiences with me.

For benefit of the curious who asked, as well as for my own benefit here, I 
shall attempt later to summarize everyones' answers, and condense them in a 
presentable way that may (or may not!) be a good source of reference material 
for possible future use...

Stay tuned---and many thanks again to all who took the time to write...

~73!~ de Eddy VE3CUI - VE3XZ
_
Topband Reflector

Re: Topband: Elevated Radials

[Tom W8JI]

Forgive me, please, if I'm re-hashing a bit of the ...same-old, same-old 
here, but I am really curious as to any real world experiences that 
might be out there in the matter of elevated radials, vs. those that are 
simply laid atop the ground...


(A) Is it true that a couple of elevated radials are just as effective as 
the optimum amount of buried ones...?


Probably not a couple, but almost certainly in small systems a few 
elevated radials are better than the same number of buried radials.


Everyone would like this to be a cookie cutter answer, but the actual 
results depend heavily on the soil and installation. Even N6LF warns over 
and over that his data only applies for conditions like his.



(B) What is the ideal number of elevated radials that one should use...?


As many as you can. More never hurts the signal, it just is more work.


(C) How many elevated radials are just enough...?


It depends on the soil, the height, the antenna, and what you want.


(D) How high should these radials be...?


It depends on the antenna, soil, and installation. Radial height takes away 
from the effective antenna height. Certainly the safest thing is about .05 
WL , unless the antenna is really short and that takes away significant 
radiator height.



(E) Would it be a requirement that I raise the feedpoints of my L's to 
the same height as the elevated radials, or can I simply leave the bases 
where they are now (at ground level)  simply slant the radials upward 
with no effect upon performance...?




It probably doesn't make much difference.



(F) Is it OK to bend the elevated radials to fit property allotments...?


It depends on where they are bent. The best practice is straight and 
symmetrical.




(G) What is the desirable length of an elevated radial...?


1/4 wave resonant length.

(H) Should any existing connections to real earth at the base of the L's 
(i.e. a ground pipe) be completed severed with a system of elevated 
radials...?


If the resonant radials are grounded to an earth ground, the system will 
lose efficiency. This much is always the case.


Pick the particular story you like Eddy, that's what most people do.  :) 
Read the fine print though. N6LF, whose study is one of the most 
comprehensive is a good source for that particular test condition. Most 
people seem to miss this:


http://www.antennasbyn6lf.com/2012/02/elevated-radial-ground-systems-some-cautions.html

What he writes isn't often what people actually paraphrase.

73 Tom 


_
Topband Reflector

Re: Topband: Elevated Radials

[Paul Christensen]

This white paper, written by Clarence Beverage may be of interest to the 
discussion:


http://www.commtechrf.com/documents/nab1995.pdf

Paul, W9AC


- Original Message - 
From: ZR z...@jeremy.mv.com
To: Guy Olinger K2AV olin...@bellsouth.net; Eddy Swynar 
deswy...@xplornet.ca

Cc: topband@contesting.com
Sent: Friday, March 01, 2013 9:53 PM
Subject: Re: Topband: Elevated Radials





Elevated radials avoid a collection of lossy mistakes that one finds
in less than optimal buried/on ground radials.  If a full size radial
system is done properly, dense, uniform all around, you will not be
able to tell the difference.  If there were huge efficiency issues
with buried radials never seen with elevated, you would be seeing
elevated radials at AM BC stations all over the place.

24 radials on the ground is not optimal unless you are over midwest
USA flat-land black super-dirt.

73, Guy.



Ahh, but the BCB folks have been using elevated radials mostly in rebuilds 
of failed buried systems as new station construction is at a 
minimumthere aint no more room unless they get rid of one sideband or 
run real QRP at night high up the band. One of the locals here runs 2.5W 
at night but being in a salt water marsh they do cover their assigned in 
town area well.


Carl
KM1H


_
Topband Reflector 


_
Topband Reflector

Re: Topband: Elevated Radials

[Eddy Swynar]

Good Day Again All,

Well, I've done my best to summarize all the respondents' comments in the 
matter of elevated vs. ground-mounted radials---and I'll try now to summarize 
these in a single-page format for benefit of all to see...

The results are certainly interesting, and some are as different from one 
another as we might be physically! 

In any event---and FWIW---here goes:


(A) Is it true that a couple of elevated radials are just as effective as the 
optimum amount of buried ones...?

-It depends.
-Don't know.
-Don't know.
-If 2 or more are used, maybe.
-It depends.


(B) What is the ideal number of elevated radials that one should use...?

-It depends upon their height.
-2.
-2 to 4.
-7 to 8.
-1 to 5.
-2.
-8.
-1 to 2.
-16 to 32.
-16 to 32.
-The more the better.
-Any amount, but use pairs (ex. 2 to 4, 6 to 8, etc.).


(C) How many elevated radials are just enough...?

-Enough to overcome ground losses  establish resonance.
-2.
-2
-2.
-2.
-4.
-4 (8 is overkill).
-1.
-32.
-8.
-Depends upon soil quality


(D) How high should these radials be...?

-The higher the better to clear pedestrians, animals, etc.
-10'.
-6' to 8'.-6' to 8'.
-12' to 14'.
-7' to 8'.
-6' to 15'.
-20'.
-6' to 10'.
-8'.
-10' to 12'.
-20'.
-1' to 10' (but the higher the better).


(E) Would it be a requirement that I raise the feedpoints of my L's to the 
same height as the elevated radials, or can I simply leave the bases where they 
are now (at ground level)  simply slant the radials upward with no effect upon 
performance...?

-Gull wing arrangement OK.
-Feed point should be 8' high.
-Not sure.
-Makes no difference.
-Gull wing OK.
-Gull wing OK.
-Not sure.
-Same height as radials (to minimize ground loss).
-Makes no difference.
-Optional.


(F) Is it OK to bend the elevated radials to fit property allotments...?

-Slight bends OK.
-Yes.
-Yes.
-Yes.
-Not sure.
-Not sure.
-OK, but gradual bends only.
-No.
-Yes.
-Best kept straight.


(G) What is the desirable length of an elevated radial...?

-Quarter wave.
-Quarter wave.
-Quarter wave.
-Quarter wave.
-Quarter wave.
-Quarter wave.
-Quarter wave.
-Quarter wave.
-Quarter wave.
-Quarter wave.
-Use short radials with a common coil.
-Quarter wave + height above ground.


(H) Should any existing connections to real earth at the base of the L's 
(i.e. a ground pipe) be completed severed with a system of elevated radials...?

-If radials one quarter wave long, makes no difference.
-No ground.
-No ground.
-With a ground, there'll be noise on receive.
-NEVER ground.
-No ground.
-No ground.
-No ground.
-No ground.
-No ground.


Additionally, four respondents recommended using a choke balun at the 
feedpoint...one person avowed that a single elevated radial was the equivalent 
of 30 ground radials...another stated that 8 elevated radials were super 
good, but that even 1 to 2 would be good...another affirms that one simply can 
not beat the optimal number of buried radials...

Several recommended this site as an excellent reference as well: 
http://www.antennasbyn6lf.com/2012/02/elevated-radial-ground-systems-some-cautions.html

I personally haven't taken a look at it myself here, but it is most certainly 
on my to do list!

I hope my effort here might help dissipate some of the fog surrounding 
elevated radials, vs. ground-mounted ones---certainly there's stuff here that I 
wanna digest still...and again, I thank one  all for their feedback,  trust 
that I've done justice here to your many responses...

~73~ de Eddy VE3CUI - VE3XZ 
_
Topband Reflector

Re: Topband: Elevated Radials

[Brad Rehm]

Eddy,

If you haven't already, you might want to take a look at Rudy Severns'
site (http://www.antennasbyn6lf.com/).  A bit of reading will answer
some or most of your questions.  It's been a few years since I studied
his material--the 160m inverted-L I build then embodied many of his
findings and suggestions.  As I remember, he found very little
difference in the performance of radials an inch off of the ground and
radials 10 feet in the air.

As for the appropriate number, you can use two if you won't mind
having a less than circular pattern.  The problem with having two,
four, or even eight is that it's more difficult to distribute current
among them.  I use four radials elevated ten feet above ground.  I've
never measured current in each of them, but I have noticed that the
antenna does better in some directions than others.

As for the optimum height...  I've built elevated radial antennas with
the radials 15 feet above ground.  My minimun height would be 10 feet,
which is high enough to avoid garroting my XYL when she mows the field
with our tractor.  The one inch height that Rudy mentions resolves a
technical issue, but it's impractical from the point of view of the
guy who has to maintain them.

I don't connect the ground rod to the base of the antenna, because I
understand that an earth ground at this point would affect the pattern
and make it change behavior seasonally.  The antenna's fed with a
2.23:1 balun, which provides a near 1:1 match to 50 Ohm coax and a DC
connection from the vertical element to the coax shield.  The ground
rod wire comes up the post on which it's mounted and extends to within
1/16th of an inch of the 4-gauge wire ring to which the radials are
connected.  The coax is connected to the antenna switch about 200 ft
away and attached to the ground system there.  (The entire run of coax
is buried in PVC conduit.)

Just a few thoughts

Brad
KV5V

On Fri, Mar 1, 2013 at 8:51 AM, Eddy Swynar deswy...@xplornet.ca wrote:
 Hi Guys,

 Forgive me, please, if I'm re-hashing a bit of the ...same-old, same-old 
 here, but I am really curious as to any real world experiences that might 
 be out there in the matter of elevated radials, vs. those that are simply 
 laid atop the ground...

 My arthritic knees here are making the chore of rolling,  unrolling, my 
 seasonal 24-radials-per-L-element radials (I have THREE of them here!) just 
 that, i.e. a VERY painful chore...and barring the possibility of there being 
 a new bionic knee replacement(s) in my future, pray tell me:

 (A) Is it true that a couple of elevated radials are just as effective as the 
 optimum amount of buried ones...?

 (B) What is the ideal number of elevated radials that one should use...?

 (C) How many elevated radials are just enough...?

 (D) How high should these radials be...?

 (E) Would it be a requirement that I raise the feedpoints of my L's to the 
 same height as the elevated radials, or can I simply leave the bases where 
 they are now (at ground level)  simply slant the radials upward with no 
 effect upon performance...?

 (F) Is it OK to bend the elevated radials to fit property allotments...?

 (G) What is the desirable length of an elevated radial...?

 (H) Should any existing connections to real earth at the base of the L's 
 (i.e. a ground pipe) be completed severed with a system of elevated 
 radials...?

 This morning I happened to work a NJ station with elevated radials that 
 almost pegged the S-meter on my 751A---the short distance between us 
 notwithstanding, obviously something was working very well for him there!

 Thanks in advance  my vy

 ~73!~ de Eddy VE3CUI - VE3XZ


 _
 Topband Reflector
_
Topband Reflector

Re: Topband: Elevated Radials

[Charles W. Shaw]

Eddy,
I've been using a 85-foot high T-Top vertical with four 
elevated radials (about 19 feet high) sloped up from the ground level 
feed point, since the fall of 1994.  This antenna is supported by a 
wood pole for the radiator and with a pair of steel pipes for each of 
the radials; however the outer pipes are 60 feet from the end of the 
radial wires.  I offer these answers based only on my observations/experience.


(A) Is it true that a couple of elevated radials are just as 
effective as the optimum amount of buried ones...?

I very much doubt it.  More than 2 elevated radials--perhaps so.


(B) What is the ideal number of elevated radials that one should use...?

I have heard that some say about eight.


(C) How many elevated radials are just enough...?

Probably my four.  I wish I had eight!


(D) How high should these radials be...?

I believe higher is better--like most ground plane antennas.

(E) Would it be a requirement that I raise the feedpoints of my 
L's to the same height as the elevated radials, or can I simply 
leave the bases where they are now (at ground level)  simply slant 
the radials upward with no effect upon performance...?
You can slant them up (gull wing) as I do.  Mine are slanted 
at about 45 degrees.  I wish the slant was much more gradual, but it 
wasn't possible.  [Less interaction/cancellation with the radiating 
part.]  I think mine hurt the desired signal to a small(?) 
degree.  Some articles below indicate that performance can  be affected.



(F) Is it OK to bend the elevated radials to fit property allotments...?

No experience here.   I would guess it is largely a matter of degree.


(G) What is the desirable length of an elevated radial...?
According to an article by Al Christman [More on Elevated 
Radials, QST, March 1993, page 72]:  1/4 wave plus the height of the 
radial above ground.  This is what I have used.


(H) Should any existing connections to real earth at the base of the 
L's (i.e. a ground pipe) be completed severed with a system of 
elevated radials...?

I firmly believe that elevated radials should never be grounded.

Here are the references I used in designing my antenna:
1.  Arch Doty, CQ, April 1984, page 24.  Mainly for his 
bibliography which is extensive.
2.  Al Christman, QST, August 1988, page 35; and the correction 
notice in QST, October 1988, page 44.
3.  Al Christman, IEEE Transactions on Broadcasting, Vol. 37. N0. 
3. September 1991.

4.  Al Christman, QST, March 1993, page 72.
5.  Paul Pagel, QST, July 1991, page 49.

See these more recent articles also:
1.  Don Nott, Radio Guide, August 2006, page 8.  Refers to 
experience with AM broadcast antennas.
2.  Rudy Severns, N6LF.  His excellent WWW 
pages  http://www.antennasbyn6lf.com/  especially hisarticles for 
QEX on his Experiments No. 3 and No. 5.


Good luck and 73,
Charles Shaw - N5UL
Hobbs, NM


 
_

Topband Reflector

Re: Topband: Elevated Radials

[Guy Olinger K2AV]

I'll try to keep this concise.

My assumption in this is that you want to do as well as possible with
the least loss possible. If instead, you are past dealing with lots of
mechanics and that's why you even dare to mention two elevated
radials, but you don't want to pick up a lot of loss, I suggest you
install FCP's and forget it **.   Otherwise, here's radials..

 (A) Is it true that a couple of elevated radials are just as effective as the 
 optimum amount of buried ones...?  If you have to ask this, you've clearly 
 never had an optimal buried radial system.

NO. An optimal buried radial system will exceed, significantly better,
or crush two elevated radials, over excellent, average or awful dirt
respectively. Two elevated was a popular scheme a decade or two ago.
Ask W3LPL this question for a brutal refutation of this urban legend.

 (B) What is the ideal number of elevated radials that one should use...?

Somewhere between 16 and 32 it gets hard to see any further change.
For commonly achievable 160m heights of radials, the degree of change
depends some on height and more on quality of ground.

 (C) How many elevated radials are just enough...?

Depends on how many dB you want to throw away.  If you can, do 12 to
16. 32 is the kill-the-loss, never-look-back number.

 (D) How high should these radials be...?

8 feet to get above antlers, hands, etc.  Given that you don't want to
garrot a neighbor, or have male deer running through take down your
radials, the height is more of a mechanical, safety issue.

 (E) Would it be a requirement that I raise the feedpoints of my L's to the 
 same height as the elevated radials, or can I simply leave the bases where 
 they are now (at ground level)  simply slant the radials upward with no 
 effect upon performance...?

First see the answer to (D), then:  Having a base-of-wire feed near
the ground puts a large RF field in the dirt that is a lot of loss and
needs dense radials to counter. Having the base of the wire up at 8
feet, and significantly reducing that field in the ground, is one of
the benefits you throw away by not going up with the feed point.
Moving fields up and away from lossy ground is a plus.  Other than
dissipating lightning energy, and giving you something to put tower
bases in, consider ground your lossy enemy that you need to evade.

 (F) Is it OK to bend the elevated radials to fit property allotments...?

Elevated radials need to carry uniform current close in to the feed so
that you get good field cancellation. Each radial in your system needs
to have the same apparent feed impedance to make sure that the current
distributes equally when you hook them together. If you have to fold
them much at all, you may need to shorten ALL of them.

 (G) What is the desirable length of an elevated radial...?

If you have the space for it all the way around, and can get up 12-16,
use the quarter wave. Use an even number of radials, and make sure
that opposite radials fed like a dipole are resonant. This is the
configuration with the least problems, that always plays and offers
few surprises.

If you are constrained in your radials, then figure the longest
possible straight radial in the most confined space and use that
length for all your radials. At the base bring all the radials
together.  This will have some amount of capacitive reactance. The
more radials, the less this reactance because the radials are in
parallel. If you need to for matching reasons, put a series inductor
to cancel the reactance between the radial tie-together and the shield
connection from the coax.

Put a 160 meter rated common mode current blocking device on the coax
right at the feed.  Get an excellent one, ACTUALLY full rating on 160.
 Just do it.  Be good to yourself.

 (H) Should any existing connections to real earth at the base of the L's 
 (i.e. a ground pipe) be completed severed with a system of elevated 
 radials...?

Ground the shield of the coax coming down from the feed at the dirt.
This will be on the shack side of the common mode current block. You
do not want the coax to see either earth ground, or the dirt as a
possible counterpoise current path.

 This morning I happened to work a NJ station with elevated radials that 
 almost pegged the S-meter on my 751A---the short distance between us 
 notwithstanding, obviously something was working very well for him there!

Elevated radials avoid a collection of lossy mistakes that one finds
in less than optimal buried/on ground radials.  If a full size radial
system is done properly, dense, uniform all around, you will not be
able to tell the difference.  If there were huge efficiency issues
with buried radials never seen with elevated, you would be seeing
elevated radials at AM BC stations all over the place.

24 radials on the ground is not optimal unless you are over midwest
USA flat-land black super-dirt.

73, Guy.

** http://www.w0uce.net/K2AVantennas.html

 Thanks in advance  my vy

 ~73!~ de Eddy VE3CUI - VE3XZ


 

Re: Topband: Elevated Radials

[Jeff Blaine]

As Brad suggests, the article by N6LF in QEX debunks a ton of traditional 
lore.  Especially regarding height above ground and length.


That article seems THE place to start for anyone considering an elevated 
vertical build now.


It should be noted that the QEX article is all about a single vertical.  The 
extension from a single vertical to arrays where fields of overlapping or 
joined elevated radials would be encountered has not been made with the same 
level of experimental confirmation.  And the usual references like ON4UN's 
book are a bit non-specific by comparison as well.


73/jeff/ac0c
www.ac0c.com
alpha-charlie-zero-charlie

-Original Message- 
From: Brad Rehm

Sent: Friday, March 01, 2013 11:38 AM
To: Eddy Swynar
Cc: topband@contesting.com
Subject: Re: Topband: Elevated Radials

Eddy,

If you haven't already, you might want to take a look at Rudy Severns'
site (http://www.antennasbyn6lf.com/).  A bit of reading will answer
some or most of your questions.  It's been a few years since I studied
his material--the 160m inverted-L I build then embodied many of his
findings and suggestions.  As I remember, he found very little
difference in the performance of radials an inch off of the ground and
radials 10 feet in the air.

As for the appropriate number, you can use two if you won't mind
having a less than circular pattern.  The problem with having two,
four, or even eight is that it's more difficult to distribute current
among them.  I use four radials elevated ten feet above ground.  I've
never measured current in each of them, but I have noticed that the
antenna does better in some directions than others.

As for the optimum height...  I've built elevated radial antennas with
the radials 15 feet above ground.  My minimun height would be 10 feet,
which is high enough to avoid garroting my XYL when she mows the field
with our tractor.  The one inch height that Rudy mentions resolves a
technical issue, but it's impractical from the point of view of the
guy who has to maintain them.

I don't connect the ground rod to the base of the antenna, because I
understand that an earth ground at this point would affect the pattern
and make it change behavior seasonally.  The antenna's fed with a
2.23:1 balun, which provides a near 1:1 match to 50 Ohm coax and a DC
connection from the vertical element to the coax shield.  The ground
rod wire comes up the post on which it's mounted and extends to within
1/16th of an inch of the 4-gauge wire ring to which the radials are
connected.  The coax is connected to the antenna switch about 200 ft
away and attached to the ground system there.  (The entire run of coax
is buried in PVC conduit.)

Just a few thoughts

Brad
KV5V

On Fri, Mar 1, 2013 at 8:51 AM, Eddy Swynar deswy...@xplornet.ca wrote:

Hi Guys,

Forgive me, please, if I'm re-hashing a bit of the ...same-old, same-old 
here, but I am really curious as to any real world experiences that 
might be out there in the matter of elevated radials, vs. those that are 
simply laid atop the ground...


My arthritic knees here are making the chore of rolling,  unrolling, my 
seasonal 24-radials-per-L-element radials (I have THREE of them here!) 
just that, i.e. a VERY painful chore...and barring the possibility of 
there being a new bionic knee replacement(s) in my future, pray tell me:


(A) Is it true that a couple of elevated radials are just as effective as 
the optimum amount of buried ones...?


(B) What is the ideal number of elevated radials that one should use...?

(C) How many elevated radials are just enough...?

(D) How high should these radials be...?

(E) Would it be a requirement that I raise the feedpoints of my L's to 
the same height as the elevated radials, or can I simply leave the bases 
where they are now (at ground level)  simply slant the radials upward 
with no effect upon performance...?


(F) Is it OK to bend the elevated radials to fit property allotments...?

(G) What is the desirable length of an elevated radial...?

(H) Should any existing connections to real earth at the base of the L's 
(i.e. a ground pipe) be completed severed with a system of elevated 
radials...?


This morning I happened to work a NJ station with elevated radials that 
almost pegged the S-meter on my 751A---the short distance between us 
notwithstanding, obviously something was working very well for him there!


Thanks in advance  my vy

~73!~ de Eddy VE3CUI - VE3XZ


_
Topband Reflector

_
Topband Reflector 


_
Topband Reflector

Re: Topband: Elevated Radials

[ZR]

Hi Guys,

Forgive me, please, if I'm re-hashing a bit of the ...same-old, same-old 
here, but I am really curious as to any real world experiences that 
might be out there in the matter of elevated radials, vs. those that are 
simply laid atop the ground...


My arthritic knees here are making the chore of rolling,  unrolling, my 
seasonal 24-radials-per-L-element radials (I have THREE of them here!) 
just that, i.e. a VERY painful chore...and barring the possibility of 
there being a new bionic knee replacement(s) in my future, pray tell me:


(A) Is it true that a couple of elevated radials are just as effective as 
the optimum amount of buried ones...?



** Define a couple. As Ive said on here umpteem times everyones 
soil/ground conditions are different. Im on a hilltop with solid granite no 
more than 2' down and mostly less than that, a couple defined as 2 wouldnt 
fly here very well.





(B) What is the ideal number of elevated radials that one should use...?



**  When your antenna analyzer shows no change; in my case it was somewhere 
between 16 and 32 as I simply doubled them and there was no change in 2:1 
bandwidth or the impedance display.





(C) How many elevated radials are just enough...?



** Same as B unless you dont mind seasonal changes or have great soil. I 
probably could have done OK with 8 but I believe my success was by paying 
attention to the details and not throwing away an unknown amount of power be 
it some fraction of a dB or not. Watching the bandwidth narrow is an eye 
opener.





(D) How high should these radials be...?



**  So you can drive a fire truck or 18 wheeler under them if necessary 
otherwise 10-12' as a minimum.





(E) Would it be a requirement that I raise the feedpoints of my L's to 
the same height as the elevated radials, or can I simply leave the bases 
where they are now (at ground level)  simply slant the radials upward 
with no effect upon performance...?



**  Dont know. On mine I started at 10' and slanted to about 15' at a 45 
degree angle as per Christman and then ran thru branches in the 15-20' 
range.





(F) Is it OK to bend the elevated radials to fit property allotments...?



** I did, the West antenna was about 60' from the property line.




(G) What is the desirable length of an elevated radial...?



**  Resonant if only 2-4. Mine are approximately 130' of #16 insulated 
copper but since they all go thru branches that lowers the resonance; I 
didnt bother measuring it. Ive seen some suggest tying all the ends together 
into one big loop but havent seen any model to indicate it helps.







(H) Should any existing connections to real earth at the base of the L's 
(i.e. a ground pipe) be completed severed with a system of elevated 
radials...?



**  Yes. It helps to have a close in ground screen but not connected. For 
lightning you can connect them and a couple of rods after the ferrite 
isolation choke but be sure you have sufficient isolation to not affect the 
antenna.





This morning I happened to work a NJ station with elevated radials that 
almost pegged the S-meter on my 751A---the short distance between us 
notwithstanding, obviously something was working very well for him there!


Thanks in advance  my vy

~73!~ de Eddy VE3CUI - VE3XZ


** Ive been an elevated fan since 1990, sure beats running on the ground 
plus a screen and still not knowing if it really works as good as it could 
as I had prior to that about 5 miles away and 500' lower.


Carl
KM1H





_
Topband Reflector


-
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Checked by AVG - www.avg.com
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_
Topband Reflector

Re: Topband: Elevated Radials

[ZR]

Elevated radials avoid a collection of lossy mistakes that one finds
in less than optimal buried/on ground radials.  If a full size radial
system is done properly, dense, uniform all around, you will not be
able to tell the difference.  If there were huge efficiency issues
with buried radials never seen with elevated, you would be seeing
elevated radials at AM BC stations all over the place.

24 radials on the ground is not optimal unless you are over midwest
USA flat-land black super-dirt.

73, Guy.



Ahh, but the BCB folks have been using elevated radials mostly in rebuilds 
of failed buried systems as new station construction is at a 
minimumthere aint no more room unless they get rid of one sideband or 
run real QRP at night high up the band. One of the locals here runs 2.5W at 
night but being in a salt water marsh they do cover their assigned in town 
area well.


Carl
KM1H


_
Topband Reflector

Re: Topband: Elevated Radials Questions

[Charlie Cunningham]

Sounds like really effective approaches!  I expect that the narrowing of the
BW as you added radials was because the additional radials were reducing the
losses of the system  and therefore raising the Q. Your 130 ft radials were
fairly close to 1/4 wave resonance on 160, I would think.  I agree with you
completely about building and measurement and testing to learn the real
answers to out  antenna question,

I do have antenna modeling software that I have used very successfully on my
160 inverted Ls and various multiband antennas, including killer 5-band
quad (single feed line!) But I also take antenna analyzers, my trusty old
Millen grid-dip meter (that has retained remarkable calibration after so
MANY years) to measure what I've constructed. I'm not above taking a
receiver outdoors to ride herd on the grid-dip meter! When I was building
the 5-band quad after months of experimentation with the EZNEC programs and
carefully determining where the parasitic elements should resonate, I could
carefully put them on frequency with the dip-meter/receiver combination and
I could watch the driving-point impedance fall into line on each band as the
parasites were resonated where the model indicated.  I was rewarded with a
REMARKABLE killer  5-band antenna for 20-10 meters that was far and away
the BEST antenna that I've ever used!!  It took months of work with the
modeling program, and I learned many things about the interaction of quad
elements and developed my own means of suppressing and coping with those,
that, as  far as I know have never been really explored or published! I
suppose I should publish them some day! But I LEARNED SO MUCH!! And with
the quad I'd generally run barefoot at 100W frm the FT-1000 MP and generally
didn't wait much!! Of course, on 160, I generally turn on the 3-500
afterburner But  did work VK3 one morning with 100W to my inverted L! He
was CQ'n and I knew that a couple of other locals, including K4CIA were on
just a few KHz away, and I didn't have time to tune up the 3-500on 160, so I
just called him with what I had going at the moment!!

I should mention that I do a lot of antenna work professionally, but those
have been mostly embedded VHF and UHF antennas for electricity, gas and
water metering etc. Some other projects I have done in similar manner were a
40/30 GP for the KH1 dxpedition some  years back It was constructed from a
Radio-Shack push-up mast that we guyed, and a parallel 30 m wire and sets of
4 resonant radials for each band. We tuned and measured everyth in the
backyard of my friend, Jim, W4RS, who was up near Danville, Va at the time
We then disassembled, and packed and shipped to Howland Island by way of
Hawaii.  It was such a pleasure to be here on the receiving end in NC and
listen to  the big world-wide pile-ups on 40 and 30 fom  my home-brew
DXpedition antenna!!  Later I designed, modeled and built an 80/75 m death
-ray for Jim. It was 5 ground planes -one central driven element and four
parasitic ground plane elements  in a square around the driven element. The
parasites had shorted transmission lines of 450 ohm ladder that could be
shorted with relays and a control box in the station to switch the parasitic
ground planes from reflector to director tuning thereby enabling the array
to be steared in 8 directions aiund  the compass rose! It was a MONSTER!!  I
remember Jim calling an A61 who had a  HUGE EU pile- and on first call, the
A61 stopped and said Who's the radi0-sugar  and Jim worked him handily!
I mention that one because all of the 80m ground planes had elevated
resonant radials!

So, experience teaches me that they are worth the effort! It's worth the
effort to do the modeling and measurement and testing when doing antenna
work! :)

Regards,

Charlie, K4OTV




-Original Message-
From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of ZR
Sent: Thursday, December 13, 2012 8:51 PM
To: Grant Saviers; Dennis W0JX
Cc: topband@contesting.com
Subject: Re: Topband: Elevated Radials Questions

The only place Ive found tuned elevated radials being discussed so much is
on ham forums.

A bit over 20 years ago I installed a slanted wire 1/4 wave vertical for 160
coming off the top guy wire of a 160' tower and about 10' out.

Started with 4 radials of roughly 130', trimmed the radiator for best match
with zero reactance and measured the 2:1 bandwidth. Added 4 more radials and
the BW narrowed, added 8 more and it narrowed a bit more. Added another 16
and no change in BW so I assume the sweet spot is somewhere in the 20's at
this location and the radials starting at 12' and slowly sloping to 20' and
then thru tree branches. Just the way they were placed likely precludes any
chance of resonance. That antenna worked so well I added another, and used
nothing but coax phasing lines to switch directions or fire a figure 8
broadside. Cheap, simple and effective unless you like throwing away money
for a mailorder solution.

YMMV depending on ground effects

Re: Topband: Elevated Radials Questions

[Dennis W0JX]

Grant, you should consider putting in an additional 23 radials and put the 
radial system on or in the ground. This will eliminate any possible detuning by 
the big metal building and interaction with the RX 4 square. You said that your 
vertical T will go up to 85 feet. However, by elevating the radials 10 feet, 
your effective vertical distance is 75 feet which will allow you to shorten the 
top hat wires a bit. As an alternate, you could put down 1/8 wavelength radials 
on the ground but more of them and have a good system too.

If you must go with an elevated radial system, I recommend that you read the 
articles by Dick Weber, K5IU, who strongly advocated elevated radials shorter 
or longer than 1/4 wavelength. If shorter, then the radials are loaded with a 
small coil. If longer, then they are tuned out with a capacitor. W5UN uses 
shortened elevated radials on his 160 meter 4 square with great results. They 
are about 70% of a quarter-wave in length.

73, Dennis W0JX/8
Milan OH
___
Topband reflector - topband@contesting.com

Re: Topband: Elevated Radials Questions

[Grant Saviers]

Thanks for the comments and pointers.  The land around the antenna is 
mixed grass and forested islands so on the ground radials would be 
partially buried and partially on the surface.  Digging through the 
trees and clearing the brush is not something I want to do. Also, based 
on prior experience with verticals on metal roofs, I'm a real fan of 
elevated radials.


I am relying on the credibility of the N6LF QEX series for how well/not 
well elevated radials will work (Mar - June 2012).  I realize this work 
was all analysis with EZNEC PRO, but it seems to be the similar to 
results of others I've read.  Googling K5IU elevated radials I did 
find the 2008 N6LF article which has the experimental data as well.  His 
analysis shows there isn't much difference in losses with more than 4 
radials between 0.15 and 0.27 wavelengths long.  I've heard conventional 
wisdom is to tune radials for resonance, but the analysis for 4 or more 
radials elevated  than a couple of feet seems to indicate it is a lot 
of work for little benefit.


I also found the 2005 thread tuning elevated radials on this reflector 
quite informative.


One thing that stands out is that I may be better off with more than 7 
shorter than 130' radials.


Grant KZ1W


On 12/13/2012 12:06 PM, Dennis W0JX wrote:

Grant, you should consider putting in an additional 23 radials and put the 
radial system on or in the ground. This will eliminate any possible detuning by 
the big metal building and interaction with the RX 4 square. You said that your 
vertical T will go up to 85 feet. However, by elevating the radials 10 feet, 
your effective vertical distance is 75 feet which will allow you to shorten the 
top hat wires a bit. As an alternate, you could put down 1/8 wavelength radials 
on the ground but more of them and have a good system too.

If you must go with an elevated radial system, I recommend that you read the 
articles by Dick Weber, K5IU, who strongly advocated elevated radials shorter 
or longer than 1/4 wavelength. If shorter, then the radials are loaded with a 
small coil. If longer, then they are tuned out with a capacitor. W5UN uses 
shortened elevated radials on his 160 meter 4 square with great results. They 
are about 70% of a quarter-wave in length.

73, Dennis W0JX/8
Milan OH
___
Topband reflector - topband@contesting.com



___
Topband reflector - topband@contesting.com

Re: Topband: Elevated Radials Questions

[Chortek, Robert L]

Not to hijack the thread, but anyone have a general idea how much improvement 
one would get by going from 8 to 12 gull wing resonant elevated radials on  a 
60 foot base loaded vertical?

73,

Bob AA6VB
 
 N7LF's work also shows that more elevated radials are better than
 fewer.  Since the losses are a function of the square of the field
 intensity, spreading the E field more evenly over a larger area
 reduces losses by decreasing the peak field intensity.

___
Topband reflector - topband@contesting.com

Re: Topband: Elevated Radials Questions

[Charlie Cunningham]

HI, Grant!

A couple of things to think of.

First, as reported in the IEEE paper mentioned earlier, increasing the
number of elevated radials to more than four , yields a rather limited
benefit, This work was done by professional antenna engineers with plenty of
equipment  and resources. The point of the investigation was the development
of a viable replacement of degraded buried radial systems under broadcast
towers with elevated radials and did involve measurement of radiated field
intensity.

As for our 160 antenna with elevated radials - think of it as a ground-plane
antenna! In the case of the inverted-L the vertical monopole element is
simply bent at a convenient height to take advantage of available supports.
In the case of the tee, this can be very convenient for supporting the upper
end of the shortened monopole. Additionally, in the case of the TEE any
residual horizontally polarized radiation from the flat-top of the TEE will
be pretty much cancelled by the equal and opposite currents flowing in
opposite directions in the flat-top wires. 

Unless you are very space limited, the major advantages of RESONANT radials
are that the current maxima in the radials will occur at the antenna
feed-point. That allows the driving-point impedance to approach pure real in
a well-behaved manner - being something less than 70 ohms. (More like 35-50
ohms if you have a good radial system. Short radials introduce a reactive
component into the antenna feed that needs to be dealt with.  I expect that
using many short radials acts more like capacitive coupling to the
underlying soil and its losses  to provide and image for the vertical
monopole.

Dig, if you wish, but there is nothing magic about dirt! And it can be a
bit lossy!

I think you are on a good track!  I'll be interested to see how it turns
out! I'm very much in favor of your elevated resonant radial approach! It
has worked very well for me!  The closest I ever came with a direct ground
system was in another location where I had a very  tall pine on dam (that
I owned) of as good-sized lake!  I drove an 8-foot copper ground rod at the
edge of the lake, at the base of the inverted-L, and using my canoe, I ran
several quarter-wave radials out into the water. Worked pretty well! - With
a fairly well behaved driving-point impedance! I could see the drop in the
driving-point impedance when I ran the radials out into the water. (Turned
out that some copper sulfate had been added to the lake to kill off some
vegetation! I expect that helped!)

Since then, I've done quite well with elevated resonant radials and an
inverted L - Until a hurrlcane tilted the tall oak that was supporting the
far end of the inverted L and we had to have it taken down.)  My elevated
radials ran around the perimeter of my lot and had 90 degree bends in them
60-70 feet from the antenna feed point!

Good luck!!  If you  build it, they will come! :)

Regards,
Charlie, K4OTV

-Original Message-
From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of Grant
Saviers
Sent: Thursday, December 13, 2012 5:28 PM
To: Dennis W0JX
Cc: topband@contesting.com
Subject: Re: Topband: Elevated Radials Questions

Thanks for the comments and pointers.  The land around the antenna is mixed
grass and forested islands so on the ground radials would be partially
buried and partially on the surface.  Digging through the trees and clearing
the brush is not something I want to do. Also, based on prior experience
with verticals on metal roofs, I'm a real fan of elevated radials.

I am relying on the credibility of the N6LF QEX series for how well/not well
elevated radials will work (Mar - June 2012).  I realize this work was all
analysis with EZNEC PRO, but it seems to be the similar to results of others
I've read.  Googling K5IU elevated radials I did find the 2008 N6LF
article which has the experimental data as well.  His analysis shows there
isn't much difference in losses with more than 4 radials between 0.15 and
0.27 wavelengths long.  I've heard conventional wisdom is to tune radials
for resonance, but the analysis for 4 or more radials elevated  than a
couple of feet seems to indicate it is a lot of work for little benefit.

I also found the 2005 thread tuning elevated radials on this reflector
quite informative.

One thing that stands out is that I may be better off with more than 7
shorter than 130' radials.

Grant KZ1W


On 12/13/2012 12:06 PM, Dennis W0JX wrote:
 Grant, you should consider putting in an additional 23 radials and put the
radial system on or in the ground. This will eliminate any possible detuning
by the big metal building and interaction with the RX 4 square. You said
that your vertical T will go up to 85 feet. However, by elevating the
radials 10 feet, your effective vertical distance is 75 feet which will
allow you to shorten the top hat wires a bit. As an alternate, you could put
down 1/8 wavelength radials on the ground but more of them and have a good
system too

Re: Topband: Elevated Radials Questions

[ZR]

The only place Ive found tuned elevated radials being discussed so much is 
on ham forums.


A bit over 20 years ago I installed a slanted wire 1/4 wave vertical for 160 
coming off the top guy wire of a 160' tower and about 10' out.


Started with 4 radials of roughly 130', trimmed the radiator for best match 
with zero reactance and measured the 2:1 bandwidth. Added 4 more radials and 
the BW narrowed, added 8 more and it narrowed a bit more. Added another 16 
and no change in BW so I assume the sweet spot is somewhere in the 20's at 
this location and the radials starting at 12' and slowly sloping to 20' and 
then thru tree branches. Just the way they were placed likely precludes any 
chance of resonance. That antenna worked so well I added another, and used 
nothing but coax phasing lines to switch directions or fire a figure 8 
broadside. Cheap, simple and effective unless you like throwing away money 
for a mailorder solution.


YMMV depending on ground effects and surrounding objects. OTOH I believe 
people spend way too much time analyzing and relying on some questionable 
answers and too little time doing some basic construction work and testing.


Carl
KM1H





- Original Message - 



From: Grant Saviers gran...@pacbell.net
To: Dennis W0JX w...@yahoo.com
Cc: topband@contesting.com
Sent: Thursday, December 13, 2012 5:27 PM
Subject: Re: Topband: Elevated Radials Questions


Thanks for the comments and pointers.  The land around the antenna is 
mixed grass and forested islands so on the ground radials would be 
partially buried and partially on the surface.  Digging through the trees 
and clearing the brush is not something I want to do. Also, based on prior 
experience with verticals on metal roofs, I'm a real fan of elevated 
radials.


I am relying on the credibility of the N6LF QEX series for how well/not 
well elevated radials will work (Mar - June 2012).  I realize this work 
was all analysis with EZNEC PRO, but it seems to be the similar to results 
of others I've read.  Googling K5IU elevated radials I did find the 2008 
N6LF article which has the experimental data as well.  His analysis shows 
there isn't much difference in losses with more than 4 radials between 
0.15 and 0.27 wavelengths long.  I've heard conventional wisdom is to tune 
radials for resonance, but the analysis for 4 or more radials elevated  
than a couple of feet seems to indicate it is a lot of work for little 
benefit.


I also found the 2005 thread tuning elevated radials on this reflector 
quite informative.


One thing that stands out is that I may be better off with more than 7 
shorter than 130' radials.


Grant KZ1W


On 12/13/2012 12:06 PM, Dennis W0JX wrote:
Grant, you should consider putting in an additional 23 radials and put 
the radial system on or in the ground. This will eliminate any possible 
detuning by the big metal building and interaction with the RX 4 square. 
You said that your vertical T will go up to 85 feet. However, by 
elevating the radials 10 feet, your effective vertical distance is 75 
feet which will allow you to shorten the top hat wires a bit. As an 
alternate, you could put down 1/8 wavelength radials on the ground but 
more of them and have a good system too.


If you must go with an elevated radial system, I recommend that you read 
the articles by Dick Weber, K5IU, who strongly advocated elevated radials 
shorter or longer than 1/4 wavelength. If shorter, then the radials are 
loaded with a small coil. If longer, then they are tuned out with a 
capacitor. W5UN uses shortened elevated radials on his 160 meter 4 square 
with great results. They are about 70% of a quarter-wave in length.


73, Dennis W0JX/8
Milan OH
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