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Old September 11th 09, 11:32 PM posted to rec.radio.amateur.antenna
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"Roy Lewallen" wrote in message
...
christofire wrote:

... and when you get back, let's see some proof that all this wacky
'new-age' theory is of any practical use to mankind.

I'd be willing to bet, say, 100 UK pounds that Professor Unwin can't
create an antenna in hardware that radiates isotropically, that is, over
a whole sphere within, let's say +/-1 dB with respect to any chosen (but
constant) polarisation. Anyone wish to up the ante?

Chris


I'd be glad to, but there's no way to prove it. Measurement accuracy and
repeatability just aren't that good, especially if you're trying to do a
full 3D measurement. The closest I've seen to a 3D measurement system
actually measured just one hemisphere. It was at what used to be NRAD
(Naval Research and Development center) and before that NOSC in San Diego,
consisting of a large (100 foot diameter if I recall correctly) rotating
circular platform with a semicircular arch overhead. By rotating the
platform and moving the detector along the arch, a full hemispherical
measurement could be made. The models were physical scale models of Navy
ships having appropriately scaled antennas. Even then, though, engineers
there told me that when the measured results differed from NEC computer
model results, they tended to believe the computer results. It's extremely
difficult to make highly, or even moderately, accurate field strength
measurements.

A while back I designed an antenna for a consulting job which was simply a
two-sloping-radial ground plane made with fairly wide traces on a low-loss
PC board. George Brown, the inventor of the ground plane antenna, had
observed an omnidirectional pattern in the horizontal plane with only two
radials, but the marketing department at RCA insisted on adding two more
to make it look symmetrical before selling them. Hence the ubiquitous
4-radial design. (The pattern of the 4 radial version is more circular
above and below the horizontal plane, but not by a whole lot.) Anyway, I
was concerned that maybe the PCB or the relatively wide, flat conductors
might have a detrimental impact on the pattern circularity, so I took it
to a local lab that has a high quality anechoic chamber and ran the
pattern. When the plot was finished, the lab technician muttered "Holy
$/!%", hit the print button, grabbed a camera, and ran into the chamber to
take a picture of the antenna. Then he went around to the other folks at
the lab with the picture and plot. Seems that it was circular within about
a dB, better than their $10k reference antenna. The prototype, by the way,
was made with adhesive copper tape and an X-Acto knife and looked as crude
as it was. I can't claim that the pattern was really better than their
reference antenna because small differences in positioning of the feedline
(even though decoupled), the antenna, and anything else in the chamber can
easily cause a couple of dB of pattern deviation.

Roy Lewallen, W7EL



Interesting stuff. I think one can get a good idea what's going on by
measuring in the cardinal planes and some 45 degree cuts. It would soon
become apparent whether the antenna warrants closer inspection.

I recall seeing what you describe at NRAA and NOSC also at ASWE in
Funtington, near Portsmouth GB. There they also had an aluminium 'sea' and
copper scale models of most of the British fleet for checking the ELF to HF
patterns (scaled conductivities). For the case in hand, though, there's no
requirement for a ground plane (viz. 'spherical' in the title) so the
resulting hardware antenna could be oriented in a number of different ways
and rotated about a single axis for measurement. I've had experience of
doing this with a Lindenblad array, and measuring axial ratio at the same
time. I've also been aware of someone else's model, made using flexible PCB
material formed into a cylinder, which outperformed the brass-tube-and-rod
one we were working on!

Feed-line radiation can easily be overcome by using a small oscillator and
battery: tiny, stable ones are available nowadays. I'd be convinced if the
protagonist managed a truly isotropic pattern at just one frequency.

Chris


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Old September 12th 09, 12:36 AM posted to rec.radio.amateur.antenna
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"Art Unwin" wrote in message
...
On Sep 11, 2:37 pm, Art Unwin wrote:
On Sep 11, 1:04 pm, "Dave" wrote:

David
Forgot to mention.
Current would not be applied to the radiator itself but only to the
sheathing of homogenous particles at rest.( ie neutrinos who are part of
the
family of Leptons but still remain as particles) This way with
opposing forces in shear which includes the bending moment or twist
of the Standard Force, the chemical adhesion is broken and the
particle is elevated to achieve a straight line projection with spin.
In this event all electrical laws lie
intact and where the resistance is solely of that of radiation to
which current is applied.


ahhhh, thank you for a good laugh art... now you can go enjoy your vacation.
i couldn't see you go without mentioning your magical levitating diamagnetic
neutrinos just one more time. while you are gone try to figure out how my
ferromagnetic antennas happen to work so well without your diamagnetic
neutrinos to do their magical levitating and twisting for me.

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Old September 12th 09, 01:31 AM posted to rec.radio.amateur.antenna
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On Sep 11, 6:36*pm, "Dave" wrote:
"Art Unwin" wrote in message

...
On Sep 11, 2:37 pm, Art Unwin wrote:

On Sep 11, 1:04 pm, "Dave" wrote:


David
Forgot to mention.
Current would not be applied to the radiator itself but only to the
sheathing of homogenous particles at rest.( ie *neutrinos who are part of
the
family of Leptons but still remain as particles) This way with
opposing forces in shear which includes the bending moment or twist
of the Standard Force, the chemical adhesion is broken and the
particle is elevated to achieve a straight line projection with spin.
In this event all electrical laws lie
intact and where the resistance is solely of that of radiation to
which current is applied.


ahhhh, thank you for a good laugh art... now you can go enjoy your vacation.
i couldn't see you go without mentioning your magical levitating diamagnetic
neutrinos just one more time. *while you are gone try to figure out how my
ferromagnetic antennas happen to work so well without your diamagnetic
neutrinos to do their magical levitating and twisting for me.


Maxwells laws are all about accountability for ALL forces involved. In
non diamagnetic materials one cannot account for energy that provides
hysteresis losses.
Thus equilibrium cannot be quantisized.ie balance of vectors. If the
energy movement or decay per unit of time can be resolved then
Maxwell's laws can be modified to include losses, such that all
forces are accounted for. Until then Maxwells laws are governed by
diamagnetic materials used as radiators as they do not retain
hysteresis energy. As for "magic" one only has to play with magnets to
see evidence of elevation together with the undeniability of twist. I
welcome from you an alternative action that arises with a different
application that deviates from The Standard Model per classical
physics. As for Neutrinos,
I prefer to allude to them as particles and not Leptons which
describes particles emitted from the Sun. Unlike Cecil I cannot
explain any properties that they gain or lose or what ever on their
journey from the Sun.(Protons) Thus I am comfortable with the term
"particles" which do not suggest that "neutrinos" cannot and do not
change properties during their journey.
Especially in the light of present thinking at CERN that such
particles can penetrate to the other side of Earth when they cannot
even break the glass of a CRT which they impinge upon.
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Old September 12th 09, 01:46 AM posted to rec.radio.amateur.antenna
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On Fri, 11 Sep 2009 23:32:39 +0100, "christofire"
wrote:

I'd be convinced if the
protagonist managed a truly isotropic pattern at just one frequency.


Hi Chris,

Half-Isotropic (if you allow for total field - you didn't specify and
any protoplasm could game that loose specification) at:
http://www.qsl.net/kb7qhc/antenna/In...-1%20Field.gif

The design has been kicking around for 10+ years now at that link, and
not even original when I posted it.

As for gaming the lack of polarization spec, I might simply offer that
it doesn't matter - if you use an isotropic detecting antenna to
measure the field of this antenna model in the link. For that
isotropic detecting antenna, I would offer a golf-ball lump of coal
and a thermistor.

73's
Richard Clark, KB7QHC
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Old September 12th 09, 11:56 AM posted to rec.radio.amateur.antenna
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"Richard Clark" wrote in message
news
On Fri, 11 Sep 2009 23:32:39 +0100, "christofire"
wrote:

I'd be convinced if the
protagonist managed a truly isotropic pattern at just one frequency.


Hi Chris,

Half-Isotropic (if you allow for total field - you didn't specify and
any protoplasm could game that loose specification) at:
http://www.qsl.net/kb7qhc/antenna/In...-1%20Field.gif

The design has been kicking around for 10+ years now at that link, and
not even original when I posted it.

As for gaming the lack of polarization spec, I might simply offer that
it doesn't matter - if you use an isotropic detecting antenna to
measure the field of this antenna model in the link. For that
isotropic detecting antenna, I would offer a golf-ball lump of coal
and a thermistor.

73's
Richard Clark, KB7QHC



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.

I'm not sure what you mean by 'total field' in respect of a far-field
pattern - all induction components should be insignificant including any
'cross-field' longitudinal ones. Also, my wager is in respect of a hardware
antenna being built, not an NEC model.

Regarding your lump of coal and a thermistor - how would you connect the
thermistor? Surely that would impose some kind of polarisation however it
was done ...?

Chris




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Old September 12th 09, 12:45 PM posted to rec.radio.amateur.antenna
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"christofire" wrote in message
...

"Richard Clark" wrote in message
news
On Fri, 11 Sep 2009 23:32:39 +0100, "christofire"
wrote:

I'd be convinced if the
protagonist managed a truly isotropic pattern at just one frequency.


Hi Chris,

Half-Isotropic (if you allow for total field - you didn't specify and
any protoplasm could game that loose specification) at:
http://www.qsl.net/kb7qhc/antenna/In...-1%20Field.gif

The design has been kicking around for 10+ years now at that link, and
not even original when I posted it.

As for gaming the lack of polarization spec, I might simply offer that
it doesn't matter - if you use an isotropic detecting antenna to
measure the field of this antenna model in the link. For that
isotropic detecting antenna, I would offer a golf-ball lump of coal
and a thermistor.

73's
Richard Clark, KB7QHC



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.

I'm not sure what you mean by 'total field' in respect of a far-field
pattern - all induction components should be insignificant including any
'cross-field' longitudinal ones. Also, my wager is in respect of a
hardware antenna being built, not an NEC model.

Regarding your lump of coal and a thermistor - how would you connect the
thermistor? Surely that would impose some kind of polarisation however it
was done ...?

Chris



.... Oops, scratch that last bit - my mind must have been elsewhere! Of
course you'd just drill a hole in it.

Thinking about your lump of coal reminded me about the kinds of antenna used
in radiation hazard meters, often three short dipoles mounted mutually
perpendicularly, each with some kind of bolometer element at its centre. If
one didn't care about polarisation then perhaps a similar arrangement could
be used to transmit with a near-isotropic pattern, but that wouldn't be an
efficient solution for communication. No, the challenge for Art Unwin,
should he wish to put his money where his mouth (keyboard) is, is create and
demonstrate a hardware antenna that exhibits a spherical radiation pattern
in respect of a single polarisation. That would be useful.

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

Chris


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Old September 12th 09, 01:51 PM posted to rec.radio.amateur.antenna
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christofire wrote:
I'd be willing to bet, say, 100 UK pounds that Professor Unwin can't create
an antenna in hardware that radiates isotropically, ...


For those types of proof, it is impossible to prove a
negative. It would be akin to the police knocking
on your door and demanding that you prove that you
are not a terrorist. The onus of logical proof is
upon the one who makes the positive assertion.
--
73, Cecil, IEEE, OOTC, http://www.w5dxp.com
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Old September 12th 09, 02:25 PM posted to rec.radio.amateur.antenna
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"Cecil Moore" wrote in message
...
christofire wrote:
I'd be willing to bet, say, 100 UK pounds that Professor Unwin can't
create an antenna in hardware that radiates isotropically, ...


For those types of proof, it is impossible to prove a
negative. It would be akin to the police knocking
on your door and demanding that you prove that you
are not a terrorist. The onus of logical proof is
upon the one who makes the positive assertion.
--
73, Cecil, IEEE, OOTC, http://www.w5dxp.com



The one who has made the positive assertion is the one who has claimed that
by his new theory an antenna can be made that has a spherical radiation
pattern. I don't believe in the theory as he has laid out and I don't
believe that such an antenna can be built and demonstrated. My wager is in
respect of whether or not the protagonist can build and demonstrate such an
antenna to back up his own positive assertion.

It is in the nature of a challenge for him to take up if he wishes, and if
he does then his bet will be in respect of his positive assertion, but, of
course, he hasn't taken it up yet. If he doesn't take up the challenge then
nothing new is proved - whichever way you care to interpret that.

Chris


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Old September 12th 09, 04:23 PM posted to rec.radio.amateur.antenna
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On Sep 12, 8:25*am, "christofire" wrote:
"Cecil Moore" wrote in message

...

christofire wrote:
I'd be willing to bet, say, 100 UK pounds that Professor Unwin can't
create an antenna in hardware that radiates isotropically, ...


For those types of proof, it is impossible to prove a
negative. It would be akin to the police knocking
on your door and demanding that you prove that you
are not a terrorist. The onus of logical proof is
upon the one who makes the positive assertion.
--
73, Cecil, IEEE, OOTC, *http://www.w5dxp.com


The one who has made the positive assertion is the one who has claimed that
by his new theory an antenna can be made that has a spherical radiation
pattern. *I don't believe in the theory as he has laid out and I don't
believe that such an antenna can be built and demonstrated. *My wager is in
respect of whether or not the protagonist can build and demonstrate such an
antenna to back up his own positive assertion.

It is in the nature of a challenge for him to take up if he wishes, and if
he does then his bet will be in respect of his positive assertion, but, of
course, he hasn't taken it up yet. *If he doesn't take up the challenge then
nothing new is proved - whichever way you care to interpret that.

Chris


Google... small efficient antenna steven best
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Old September 12th 09, 05:14 PM posted to rec.radio.amateur.antenna
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"Art Unwin" wrote in message
...

Google... small efficient antenna steven best


and just what are we supposed to get out of all the links that it returns?
that someone else built some other kinds of antennas that actually work? or
that Dr Best knows more than you do?

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