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Old September 12th 09, 05:28 PM posted to rec.radio.amateur.antenna
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Default Spherical radiation pattern

On Sat, 12 Sep 2009 12:45:28 +0100, "christofire"
wrote:


Well the title of the thread is 'Spherical radiation pattern' and I
interpret that as meaning a far-field pattern that is uniform (within the
2 dB margin I offered) in respect of the transverse electric, or
transverse magnetic, field strength, or the resulting power-flux density,
over a whole sphere.


Hi Chris,

Well, simply put this antenna with its mirror image elements into free
space and it accomplishes that quite easily.

What is the red line in the pattern to which you gave the link?


XYZ Axis.

73's
Richard Clark, KB7QHC
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Old September 12th 09, 05:40 PM posted to rec.radio.amateur.antenna
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On Sat, 12 Sep 2009 08:23:17 -0700 (PDT), Art Unwin
wrote:

Google... small efficient antenna steven best


http://www.cst.com/Content/Applications/Article/A+Small,+Efficient,+Linear-polarized+Omni-directional+Antenna
The antenna fits inside a sphere of radius 0.0415 wavelengths.
However, the antenna pattern is not spherical and more closely
resembles the torus produced by a dipole than of an isotropic antenna.
http://www.cst.com/CMS/images/article105/CPU05_047_600_481.jpg

An isotropic approximation, which doesn't really qualify for the prize
because the pattern is not polarization and phase insensitive.
http://802.11junk.com/jeffl/antennas/isotropic/index.html


--
Jeff Liebermann
150 Felker St #D
http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558
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Old September 12th 09, 05:50 PM posted to rec.radio.amateur.antenna
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Default Spherical radiation pattern


"Richard Clark" wrote in message
...
On Sat, 12 Sep 2009 12:45:28 +0100, "christofire"
wrote:


Well the title of the thread is 'Spherical radiation pattern' and I
interpret that as meaning a far-field pattern that is uniform (within
the
2 dB margin I offered) in respect of the transverse electric, or
transverse magnetic, field strength, or the resulting power-flux
density,
over a whole sphere.


Hi Chris,

Well, simply put this antenna with its mirror image elements into free
space and it accomplishes that quite easily.


Have you ever built one and measured its radiation pattern?

Chris


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Old September 12th 09, 06:11 PM posted to rec.radio.amateur.antenna
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Default Spherical radiation pattern

On Sat, 12 Sep 2009 17:50:52 +0100, "christofire"
wrote:

Have you ever built one and measured its radiation pattern?


Hi Chris,

Others have - the design is not unique to me and has been around for
years. I modeled it to merely confirm those reports and that was
rather simply accomplished. I have reported these results to
interested parties here for the last 10 to 15 years. I am under no
illusion that Art has ever used that data as a resource, otherwise it
would undercut his claim of novelty.

I've no doubt that other designs meeting your terse requirements could
be rummaged up. I have no presumption that NEC fails for this one
specific design that is ordinary in every regard to conventional
modeling. At a minimum this is only 4 wires. As such, I am
satisfied.

73's
Richard Clark, KB7QHC
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Old September 12th 09, 07:25 PM posted to rec.radio.amateur.antenna
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Default Spherical radiation pattern


"Richard Clark" wrote in message
...
On Sat, 12 Sep 2009 17:50:52 +0100, "christofire"
wrote:

Have you ever built one and measured its radiation pattern?


Hi Chris,

Others have - the design is not unique to me and has been around for
years. I modeled it to merely confirm those reports and that was
rather simply accomplished. I have reported these results to
interested parties here for the last 10 to 15 years. I am under no
illusion that Art has ever used that data as a resource, otherwise it
would undercut his claim of novelty.

I've no doubt that other designs meeting your terse requirements could
be rummaged up. I have no presumption that NEC fails for this one
specific design that is ordinary in every regard to conventional
modeling. At a minimum this is only 4 wires. As such, I am
satisfied.

73's
Richard Clark, KB7QHC



Good. Maybe this will encourage Art to have a go at my challenge by
applying his own theories then.

I had seen papers about inverted F antennas before (at an IEE or IET
symposium some ten years ago), and I vaguely recall hearing that some
manufacturers use them in mobile phones, but I'd never seen a pattern as
uniform as the result of your simulation.

Chris




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Old September 12th 09, 07:37 PM posted to rec.radio.amateur.antenna
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Default Spherical radiation pattern


"christofire" wrote in message
news

"Richard Clark" wrote in message
...
On Sat, 12 Sep 2009 17:50:52 +0100, "christofire"
wrote:

Have you ever built one and measured its radiation pattern?


Hi Chris,

Others have - the design is not unique to me and has been around for
years. I modeled it to merely confirm those reports and that was
rather simply accomplished. I have reported these results to
interested parties here for the last 10 to 15 years. I am under no
illusion that Art has ever used that data as a resource, otherwise it
would undercut his claim of novelty.

I've no doubt that other designs meeting your terse requirements could
be rummaged up. I have no presumption that NEC fails for this one
specific design that is ordinary in every regard to conventional
modeling. At a minimum this is only 4 wires. As such, I am
satisfied.

73's
Richard Clark, KB7QHC



Good. Maybe this will encourage Art to have a go at my challenge by
applying his own theories then.

I had seen papers about inverted F antennas before (at an IEE or IET
symposium some ten years ago), and I vaguely recall hearing that some
manufacturers use them in mobile phones, but I'd never seen a pattern as
uniform as the result of your simulation.

Chris

art will never accept your challenge. its up to you to prove that his
assertions are incorrect... and then get ignored as he continues to state
the same things in many different forms. unless you can capture one of his
diamagnetic levitating solar neutrinos and show that it doesn't sit on the
antenna element and jump off when a pulse of current hits it you will never
be believed... and even if you did capture one he would tell you it changed
in flight from the sun.

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Old September 12th 09, 08:13 PM posted to rec.radio.amateur.antenna
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Default Spherical radiation pattern

On Sat, 12 Sep 2009 19:25:16 +0100, "christofire"
wrote:

I had seen papers about inverted F antennas before (at an IEE or IET
symposium some ten years ago), and I vaguely recall hearing that some
manufacturers use them in mobile phones, but I'd never seen a pattern as
uniform as the result of your simulation.


Hi Chris,

For a more academic treatment, the antenna is also known as the
"U-Shaped Antenna of Shtrikman." His has three wires, my fourth wire
is much like the J-Pole feed point attachment.

Now, one proviso: this is not an isotropic in the sense of providing
equal polarization at any angle. Nothing can accomplish that due to
that requirement being impossible to meet (the so-called "hairy ball"
problem). So, I simply resolved that with my carbon golf ball with
its thermistor for detecting the Inverted F's total field to within
the degree of less than 2dB variation over the shell surrounding the
antenna.

Good. Maybe this will encourage Art to have a go at my challenge by
applying his own theories then.


As I've shown, they are not his theories. Art doesn't have theories,
they are illusions. Shtrikman's antenna has a model and a practical,
real example that agree with one another in performance. The design
is revealed and can be reproduced by anyone. No advanced math is
demanded to perfect the results. No allusion to nuclear forces is
required to explain any principle. Anyone can, and HAS built an
antenna that Art can only mumble about. Perhaps I am mislead about
this mumble, having kill-filed him, as I see his contribution (sic)
only through other's quotes; few of which are full quotes (I can
understand why).

This last week in my driving through rain city, I've seen a street
corner beggar who has worked one particular intersection for a couple
of years now. He has a weather protected laminated board describing
his plea, and he wears goretex weather gear that I couldn't afford. He
does have this hang-dog appearance and shambling shuffle tho'. What is
one to believe when it comes to claims? Clearly money talks. Who
knows? He may have a patented system and sells franchises.

73's
Richard Clark, KB7QHC
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Old September 13th 09, 02:08 AM posted to rec.radio.amateur.antenna
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Default Spherical radiation pattern


"Richard Clark" wrote in message
...
On Sat, 12 Sep 2009 19:25:16 +0100, "christofire"
wrote:

I had seen papers about inverted F antennas before (at an IEE or IET
symposium some ten years ago), and I vaguely recall hearing that some
manufacturers use them in mobile phones, but I'd never seen a pattern as
uniform as the result of your simulation.


Hi Chris,

For a more academic treatment, the antenna is also known as the
"U-Shaped Antenna of Shtrikman." His has three wires, my fourth wire
is much like the J-Pole feed point attachment.

Now, one proviso: this is not an isotropic in the sense of providing
equal polarization at any angle. Nothing can accomplish that due to
that requirement being impossible to meet (the so-called "hairy ball"
problem).


I had understood it to be impossible on the basis of normal physics but Art
Unwin's claim wasn't clear in respect of polarisation.


So, I simply resolved that with my carbon golf ball with
its thermistor for detecting the Inverted F's total field to within
the degree of less than 2dB variation over the shell surrounding the
antenna.


Now I understand what you meant by 'total field' - sum of powers of
components in all polarisations.


Good. Maybe this will encourage Art to have a go at my challenge by
applying his own theories then.


As I've shown, they are not his theories. Art doesn't have theories,
they are illusions. Shtrikman's antenna has a model and a practical,
real example that agree with one another in performance. The design
is revealed and can be reproduced by anyone. No advanced math is
demanded to perfect the results. No allusion to nuclear forces is
required to explain any principle. Anyone can, and HAS built an
antenna that Art can only mumble about. Perhaps I am mislead about
this mumble, having kill-filed him, as I see his contribution (sic)
only through other's quotes; few of which are full quotes (I can
understand why).


Shtrikman's antenna sounds interesting. I will look up references.


This last week in my driving through rain city, I've seen a street
corner beggar who has worked one particular intersection for a couple
of years now. He has a weather protected laminated board describing
his plea, and he wears goretex weather gear that I couldn't afford. He
does have this hang-dog appearance and shambling shuffle tho'. What is
one to believe when it comes to claims? Clearly money talks. Who
knows? He may have a patented system and sells franchises.

73's
Richard Clark, KB7QHC


Over here we've recently been subjected to the phenomenon of 'Seasick
Steve' - who 'started out with nothing and still has most of it left' but
also has a substantial recording contract. What is one to believe, as you
so rightly say?

Chris


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Old September 13th 09, 07:20 AM posted to rec.radio.amateur.antenna
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On Sun, 13 Sep 2009 02:08:20 +0100, "christofire"
wrote:

I had understood it to be impossible on the basis of normal physics but Art
Unwin's claim wasn't clear in respect of polarisation.


Hi Chris,

Black body radiators do qualify as Isotropic; and as Art has claimed
high efficiencies for RF impracticalities, it must be for efficient
Infrared emission.

73's
Richard Clark, KB7QHC
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Old September 13th 09, 10:37 AM posted to rec.radio.amateur.antenna
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"christofire" wrote
...


Now I understand what you meant by 'total field' - sum of powers of
components in all polarisations.


Does one wave has many polarizations, or one antenna has many polarizations?
Which one: transmitter or receiver? Could you teach me?
A*

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