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-   -   Current in antenna loading coils controversy (https://www.radiobanter.com/antenna/670-current-antenna-loading-coils-controversy.html)

Mark Keith November 15th 03 03:33 AM
(Richard Harrison) wrote in message ...
Mark Keith wrote:
"But I still feel I`m already building mine as well as they can be."

Close the patent office!

Best regards, Richard Harrison, KB5WZI

Nothing to patent. I didn't invent them. I think I see now why Roy
bailed out.
It's starting to get silly.
We are talking about something that is already very well known. Or at
least when applied to mobile antennas. There is nothing new about
optimizing the coil location to improve current distribution. The
various heights above the base have been hashed out and tested
ad-nausium till the cows come home. There is nothing new about using
a top hat to improve current distribution. Ditto on the
testing...There is nothing new about ground losses usually
overshadowing coil losses with most mobile setups. Yuri tells me to go
back to my rubber room, but read his previous post first,and I did.
But I see nothing there that is new as far as pertaining to mobile
antenna design. Not a single thing. Now if it's proven that errors
could been seen when modeling arrays, or whatever, I can see that as
useful. Not that I'm convinced it's a major problem yet mind you...But
I could see finding usable modeling improvement with complex arrays
much more likely than the lowly whip and coil.
When it comes to mobile antennas, I think they have pretty much
reached the state of the art as far as the design of a coil loaded
short antenna goes. All variations of loading positions have already
been tested virtually non stop since at the very least the 50's, when
bugcatchers became very common. I've got a 1935 QST with a mobile on
the front, but he's not using a bugcatcher. Crap, what more can you
do with a simple whip and coil....:/ They have been beat to death
looking for the very last drop for 50 solid years. I've personally
beat them to death myself looking for the last drop since at least
1988-89 or so when I got my first mobile radio. Trust me, I can't
really improve over what I have now without getting ridiculous or
undrivable or too heavy. I'm already over the legal 13.6 ft height
limit as it is. My coil is already elevated from the base 50% when
driving, "10 ft antenna, with the base 4.5 ft off the ground" 62% up
when parked with the lower mast. "13 ft antenna" With the 13 ft
version, my coil is higher than some peoples whole antenna. Appx 12.5
ft off the ground.
I can't physically install the coil any higher than that due to the
fiberglass mast I use for the lower main section. I installed the coil
at the very top, and use a 5ft thin stinger whip above the coil. It
wouldn't help a whole lot more anyway. It's better to keep the same
longer stinger length and add mast below the coil. Heck, I agree with
almost everthing he promotes as far as mobile antenna design as far as
coil placement, hats, etc. But it's sure nothing new or earthshaking.
I've seen nothing so far to indicate we are designing in gross error
or even noticable error. I've seen nothing to indicate that any new
data gleaned from his tests will improve mobile antenna design enough
to notice in FS measurements. He suggests nothing new that already
isn't being utilized. Where's the all important beef?
I'm not trying to be difficult, I'm just asking the fairly obvious. I
ask very simple questions and what do I get? Bafflegab deflection
tactics, rehashes of past social dilemmas, or just vague, totally
useless comments from one. I think I'm gonna bail on this thread also.
I have better things to do than chase my tail and bark at the moon. My
position on the current state of mobile antenna design is fairly well
known at this point. I'll just leave it at that. MK

Richard Harrison November 15th 03 03:58 PM
Mark Keith wrote:
"I`ve seen nothing so far to indicate we are designing in gross error or
even noticible error."

Neither have I. But, I`ve read several stimulating perceptions which
were new to me and motivated me to investigate and improve my
understanding.

I am sorry My statement, "Close the patent office!" offended Mark. I
have no doubt that Mark has optimized his mobil antennas.

Forty years after Faraday suggested the existence of electric fields in
about 1842,
Heinrich Hertz built a spark transmitter and receiver. The receiver was
just a loop with a gap which sparked when Hertz keyed his transmitter.
It was resonant at 53 MHz or near the frequencies now assigned as TV
Channel 2 in the USA. Hertz optimized his antennas for maximum
transmission distance and achieved about 30 feet.

In the last 160 years there have been many interesting antenna
developments and more are yet to come. Most are not likely predictable.

Best regards, Richard Harrison, KB5WZI

Art Unwin KB9MZ November 15th 03 07:00 PM
(Mark Keith) wrote in message om...
 (Richard Harrison) wrote in message ...
Mark Keith wrote:
"But I still feel I`m already building mine as well as they can be."

Close the patent office!

Best regards, Richard Harrison, KB5WZI

Nothing to patent. I didn't invent them. I think I see now why Roy
bailed out.
It's starting to get silly.
We are talking about something that is already very well known. Or at
least when applied to mobile antennas. There is nothing new about
optimizing the coil location to improve current distribution. The
various heights above the base have been hashed out and tested
ad-nausium till the cows come home. There is nothing new about using
a top hat to improve current distribution. Ditto on the
testing...There is nothing new about ground losses usually
overshadowing coil losses with most mobile setups. Yuri tells me to go
back to my rubber room, but read his previous post first,and I did.
But I see nothing there that is new as far as pertaining to mobile
antenna design. Not a single thing. Now if it's proven that errors
could been seen when modeling arrays, or whatever, I can see that as
useful. Not that I'm convinced it's a major problem yet mind you...But
I could see finding usable modeling improvement with complex arrays
much more likely than the lowly whip and coil.
When it comes to mobile antennas, I think they have pretty much
reached the state of the art as far as the design of a coil loaded
short antenna goes.

Can you tell me where I can find what the orientation of coil cross
section does for efficiency ?
There are circular cross sections, edge wound cross sections and also
the ribbon type that Collins uses where the ribbon is coiled on a
adjacent coil former, why did they choose this method?
I am pursuing efficiency, reduction of losses and Collins have a great
reputation so which form is the state of the art especially with
corner flux density.
Another question is that if we split up an inductance into two parts
does the form factor include the summation of inductances or does the
distance inbetween
where coil linkage is not fully formed affect efficiency for the
worse.
Discussion like this thread hopefully will enlarge our education to
see if such things matter . Another question I struggle with is to put
another element inside the coil where there is max flux density but
again it can't be resolved by modeling. With the multi antenna experts
onboard it is always a possibility that a modicom of information will
be provided that will benefit all.
As far as inductances, all is not known to my mind and I always would
like to be privy to more information, and not because I want to build
a whip






All variations of loading positions have already
been tested virtually non stop since at the very least the 50's, when
bugcatchers became very common. I've got a 1935 QST with a mobile on
snipThey have been beat to death
looking for the very last drop for 50 solid years. I've personally
beat them to death myself looking for the last drop since at least
snip Where's the all important beef?
I'm not trying to be difficult, I'm just asking the fairly obvious. I
ask very simple questions and what do I get? Bafflegab deflection
tactics, rehashes of past social dilemmas, or just vague, totally
useless comments from one. I think I'm gonna bail on this thread also.
I have better things to do than chase my tail and bark at the moon. My
position on the current state of mobile antenna design is fairly well
known at this point. I'll just leave it at that. MK

Regards
Art

Wes Stewart November 16th 03 05:49 AM
On 15 Nov 2003 11:00:19 -0800, (Art Unwin KB9MZ)
wrote:


|Can you tell me where I can find what the orientation of coil cross
|section does for efficiency ?

Michaels ("Loading Coils for 160-Meter Antennas", QST, April 1990, pp
28-31) might help.

|There are circular cross sections, edge wound cross sections and also
|the ribbon type that Collins uses where the ribbon is coiled on a
|adjacent coil former, why did they choose this method?

I believe the Collins ribbon inductors were designed for variability,
i.e., tunable without any sliding contacts as in roller inductors.

|I am pursuing efficiency, reduction of losses and Collins have a great
|reputation so which form is the state of the art especially with
|corner flux density.
|Another question is that if we split up an inductance into two parts
|does the form factor include the summation of inductances or does the
|distance inbetween
|where coil linkage is not fully formed affect efficiency for the
|worse.
|Discussion like this thread hopefully will enlarge our education to
|see if such things matter . Another question I struggle with is to put
|another element inside the coil where there is max flux density but
|again it can't be resolved by modeling. With the multi antenna experts
|onboard it is always a possibility that a modicom of information will
|be provided that will benefit all.
|As far as inductances, all is not known to my mind and I always would
|like to be privy to more information, and not because I want to build
|a whip

Another interesting reference is Rhea ("Filters and an Oscillator
Using a New Solenoid Model", Applied Microwave & Wireless, November
2000, pp 30-42) In a nutshell, his premise is that the classic
inductor model is in error, particularly with respect interwinding
capacitance.

Some other articles that should be read by all participating in this
thread are by Cebik.

http://www.cebik.com/amod/amod13.html

http://www.cebik.com/amod/amod14.html

Art Unwin KB9MZ November 16th 03 06:12 PM
Wes Stewart wrote in message . ..
On 15 Nov 2003 11:00:19 -0800, (Art Unwin KB9MZ)
wrote:


|Can you tell me where I can find what the orientation of coil cross
|section does for efficiency ?

Michaels ("Loading Coils for 160-Meter Antennas", QST, April 1990, pp
28-31) might help.

|There are circular cross sections, edge wound cross sections and also
|the ribbon type that Collins uses where the ribbon is coiled on a
|adjacent coil former, why did they choose this method?

I believe the Collins ribbon inductors were designed for variability,
i.e., tunable without any sliding contacts as in roller inductors.

|I am pursuing efficiency, reduction of losses and Collins have a great
|reputation so which form is the state of the art especially with
|corner flux density.
|Another question is that if we split up an inductance into two parts
|does the form factor include the summation of inductances or does the
|distance inbetween
|where coil linkage is not fully formed affect efficiency for the
|worse.
|Discussion like this thread hopefully will enlarge our education to
|see if such things matter . Another question I struggle with is to put
|another element inside the coil where there is max flux density but
|again it can't be resolved by modeling. With the multi antenna experts
|onboard it is always a possibility that a modicom of information will
|be provided that will benefit all.
|As far as inductances, all is not known to my mind and I always would
|like to be privy to more information, and not because I want to build
|a whip

Another interesting reference is Rhea ("Filters and an Oscillator
Using a New Solenoid Model", Applied Microwave & Wireless, November
2000, pp 30-42) In a nutshell, his premise is that the classic
inductor model is in error, particularly with respect interwinding
capacitance.

Some other articles that should be read by all participating in this
thread are by Cebik.

http://www.cebik.com/amod/amod13.html

http://www.cebik.com/amod/amod14.html

Thank you for those references Wes. I really didn't expect to hear
from you again. I now have the computor program to simulate my actual
antenna so efficiency is now of major importance ,I can up my
efficiency to 50 per cent
by hanging a wire down from the dipole ends which I am not comfortable
about
and would rather aproach the coil for loss reduction and go for a beam
setup
by using the radiation efficiently by making it fully directional
stead of figure 8 form
and hopefully I can get those extracts

Reg I tried to enter your page once but I am so computor incompetant.
Looked at a tank circuit today and it was wound flat ribbon form!

Looking forward to looking at this fresh info
Many thanks to both of you
Art

Richard Harrison November 17th 03 02:17 AM
Art, KB9MZ wrote:
"I can up my efficiency to 50 per cent by hanging a wire down from the
dipole ends which I am not comfortable about---."

Why would Art be uncomfortable about improving efficiency by hanging a
wire down?
Maybe he does not believe his model is correct. Maybe he doesn`t want
some directivity change that comes with hanging a wire down. Maybe there
is some physical problem with hanging a wire down.

The problem with a loading coil is increased loss. Capacitance is
usually low loss.

As Yuri, K3BU has noted, there is much to be learned from reading
ON4UN`s Chapter 9 about antenna loading even though everything regarding
vertical antennas doesn`t translate readily to horizontal antennas.

ON4UN includes horizontally polarized antennas in "Low-Band DXing". It`s
easy to read, well illustrated, and full of good references. It helps if
you want to design your own antenna because it tells why as well as how.

Best regards, Richard Harrison, KB5WZI

Reg Edwards November 17th 03 03:07 AM
Reg I tried to enter your page once but I am so computor incompetant.

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

Art, I'm afraid there's not much hope for you then.

Why not try keeping tropical fish ? It's very relaxing although it can be
livened up by introducing just one pirana to the tank. ;o)
----
Yours, Reg

Cecil Moore November 17th 03 05:20 PM
David J. Windisch wrote:
Speaking of pirhanas in the tank, this humble lurker and scribe takes this
opportunity to thank and congratulate you pirhanas posting here for driving
the likes of ... et al., right off this reflector with your feeding frenzies
over triviae, minutiae, and inconsequential stuff.

A larger question might be: Why do some (not all) of those guys stake their
reputations and egos on that very "triviae, minutiae, and inconsequential stuff"?

Some of those guys on your list disagree loud and long with each other, both
sides determined never to admit a mistake of any kind. Many list their degrees
and accomplishments as if those things are a vaccination against mistakes.

Driving a person off a public unmoderated newsgroup is impossible. What causes
people to leave this newsgroup under pressure is pride plus the heat in the kitchen.

Do you think we really need a newsgroup guru upper class whose assertions are
immune from other questioning minds?
--
73, Cecil http://www.qsl.net/w5dxp



-----= Posted via Newsfeeds.Com, Uncensored Usenet News =-----
http://www.newsfeeds.com - The #1 Newsgroup Service in the World!
-----== Over 100,000 Newsgroups - 19 Different Servers! =-----

Wes Stewart November 17th 03 05:25 PM
On Mon, 17 Nov 2003 05:56:29 -0500, "David J. Windisch"
wrote:

|Speaking of pirhanas in the tank, this humble lurker and scribe takes this
|opportunity to thank and congratulate you pirhanas posting here for driving
|the likes of Gary Coffman, Tom Rauch, Tom Bruhns, Bart Rowlett, Steve Best,
|Bob Haviland, Roy Lewallen, Wes Stewart, Ian White, Walt Maxwell, Joe
|Reisert .... et al., right off this reflector with your feeding frenzies
|over triviae, minutiae, and inconsequential stuff.


While I'm honored to be counted among the others you speak of Dave, I
think you're not lurking often enough g.

I must say that some of us on the list are still here. I don't know
the reasons why some of the others are not regulars anymore; it could
be what you cite or it could just be the press of other things in
life. I too miss their contributions.

Nevertheless, it's just usenet and not something to be taken very
seriously or to get upset about. The thin skinned should not apply
g.

Actually, I think some of the participants in the latest thread might
be off dreaming up some experiments or new models to bring back to the
discussion. Notwithstanding the bullheadedness and wacky thinking of
some of the usual suspects, there has been some thought provoking
discussion.

Regards,

Wes N7WS

Art Unwin KB9MZ November 18th 03 12:45 AM
(Richard Harrison) wrote in message ...
Art, KB9MZ wrote:
"I can up my efficiency to 50 per cent by hanging a wire down from the
dipole ends which I am not comfortable about---."

Why would Art be uncomfortable about improving efficiency by hanging a
wire down?
Maybe he does not believe his model is correct. Maybe he doesn`t want
some directivity change that comes with hanging a wire down. Maybe there
is some physical problem with hanging a wire down.

The problem with a loading coil is increased loss. Capacitance is
usually low loss.

Richard
seem like a sentence got dropped,
What is it that you want to know ?
Are you suggesting using a capacitive coupling instead of
the use of an inductor.........
I think you need to rewrite the post so I can see what your needs are
Regards
Art



As Yuri, K3BU has noted, there is much to be learned from reading
ON4UN`s Chapter 9 about antenna loading even though everything regarding
vertical antennas doesn`t translate readily to horizontal antennas.

ON4UN includes horizontally polarized antennas in "Low-Band DXing". It`s
easy to read, well illustrated, and full of good references. It helps if
you want to design your own antenna because it tells why as well as how.

Best regards, Richard Harrison, KB5WZI


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