On Fri, 4 Sep 2009 00:56:39 -0700 (PDT), wrote:

Sure, you can get fairly close to isotropic with the right
system, but how are you going to do it by tipping a
vertical? The likely results do not fit my idea of isotropic.

I forgot to connect my comments to the original question. Sorry(tm).
You're correct. There's no way to get a good isotropic radiator
pattern with a simple vertical radiator. However, you can still get
fairly close if you make the antenna sufficiently small relative to
the operating wavelength. As the physical antenna size approaches a
point radiator, the pattern starts to look rather spherical.
Unfortunately, the gain drops, efficiency drops, and feed point
impedance drops, resulting in a rather inferior antenna.

There's also a question of how close to perfection does the spherical
pattern need to become? Within 0.1dB, 1dB, 3dB, etc???? Offhand, I
would guess anything within a few dB of spherical could be considered
isotropic, as in all the patents I noted.

--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

wrote in message
...
On Sep 3, 10:33 am, Art Unwin wrote:
And I imagine that there are still many readers world wide
who are still wondering what constitutes "equilibrium" in
an antenna system.

not any more, he defined it just the other day, equilibrium==isotropic.

"Szczepan Bialek" wrote in message
...

"An isotropic radiator is a theoretical point source of waves which
exhibits the same magnitude or properties when measured in all
directions".
The only way to make the real point source is the proper tipping. Of
course it must be a monopole.

another blabbering idiot chiming in... a monopole can't have the same
properties in all directions since it is linear, no matter how much you tip
it!

"Art Unwin" wrote in message
...
On Sep 3, 6:14 pm, "Dave" wrote:
David, you can find the famous "exclusion principle" by Wolfgang Pauli
in any book on Quantum Mechanics.

ah, bringing the Pauli Exclusion Principle in on the discusion now, that is
a new one i think... can we now not have any of your magical levitating
diamagnetic neutrinos on an antenna in the same quantum states??

Dave wrote:

"Art Unwin" wrote in message
...
On Sep 3, 6:14 pm, "Dave" wrote:
David, you can find the famous "exclusion principle" by Wolfgang Pauli
in any book on Quantum Mechanics.

ah, bringing the Pauli Exclusion Principle in on the discusion now, that
is a new one i think... can we now not have any of your magical
levitating diamagnetic neutrinos on an antenna in the same quantum states??

Drum roll........

From the department of everything you knew about physics is wrong
department......


The Coriolis effect upon RF radiation has some interesting other
ramifications.
Since Coriolis affects radio waves, it follows that gravity also affects
radio waves. This bring up a new and much simplified explanation for
radio propagation. As the RF spins away from the antenna, the coriolis
effect and gravity eventually pull the signal back to earth far away
from the originating point. I always thought that that silly stuff about
atmospheric layers and ionization was kind of dum anyhow.

Each time the RF hits the earth, a new point of reference is made, and
the signal bounces up with a new twist to it.

We're still working on why UHF + signals don't do this. Maybe their
twist is going the other way, so instead of coming back down, they spin
upwards never to be seen again.


- 73 de Mike N3LI -

On Sep 4, 3:37Â*am, Szczepan BiaÅ‚ek wrote:
U¿ytkownik napisa³ w ...
On Sep 3, 10:29 pm, Jeff Liebermann wrote:



On Thu, 3 Sep 2009 19:11:42 -0700 (PDT), wrote:
How in the heck are you going to
get **ANY** vertical radiator to have a truly isotropic pattern?
It's impossible. An isotropic pattern is a theoretical pattern
in which radiation is equal in all directions. Such a pattern
does not exist with real antennas.

A real isotropic radiator may not exist, but one can get fairly close.
If you believe the model, the total error is 0.44 db. See:
http://802.11junk.com/jeffl/antennas/isotropic/index.html
The NEC2 deck is under the photo labeled "main".

I once built one of these antennas on roughly 444MHz out of cardboard
and magnet wire. The oscillator was a small crystal can oscillator
running from a 9V battery to avoid having the feed coax wrecking the
pattern. The impedance was nowhere near 50 ohms and required a bit of
matching to get the VSWR down. I'm now digging for the photos.

I used a piece of string to maintain a constant radius, a tiny pickup
loop at the end of a length of coax cable running inline with the
string, and eventually going to my antique HP spectrum analyzer. On
the 2dB/div scale, it was a fairly good approximation of an isotropic
radiator with errors mostly caused by indoor reflections and
interference with the bench.

Sure, you can get fairly close to isotropic with the right

system, but how are you going to do it by tipping a
vertical? Â*The likely results do not fit my idea of isotropic.

"An isotropic radiator is a theoretical point source of waves which exhibits
the same magnitude or properties when measured in all directions".
The only way to make the real point source is the proper tipping. Of course
it must be a monopole.
S*

Excellent. I am so happy that somebody out there is not following the
pied pipers of denial.
Thanks for your input.

"Jeff Liebermann" wrote in message
...
On Fri, 4 Sep 2009 00:56:39 -0700 (PDT), wrote:

Sure, you can get fairly close to isotropic with the right
system, but how are you going to do it by tipping a
vertical? The likely results do not fit my idea of isotropic.

I forgot to connect my comments to the original question. Sorry(tm).
You're correct. There's no way to get a good isotropic radiator
pattern with a simple vertical radiator. However, you can still get
fairly close if you make the antenna sufficiently small relative to
the operating wavelength. As the physical antenna size approaches a
point radiator, the pattern starts to look rather spherical.


That doesn't sound right. The directivity gain of an infinitesimal electric
doublet (i.e. a dipole with infinitesimal length) is about 0.4 dB less than
that of a half-wave dipole. Its similar lemniscate-of-rotation radiation
pattern results from the symmetry about its axis. The results for monopoles
derived from these forms of dipole won't be too different. It is rather
obvious that a receiving dipole of any polarisation won't receive much
signal from the end of a transmitting dipole or monopole, however it's
oriented - there's no apparent length over which unopposed current is
flowing so there's no 'moment' in that direction.

One solution to spherical radiation is the Lindenblad array (and variants
that others have chosen to re-name) which presents finite resolved
components of the lengths of some of its dipoles in all directions ... but
the tilt of the elements has nothing at all to do with Art Unwin's 'theory',
it's simply a matter of making sure there's a resolved component in each
direction. Of course, a Lindenblad designed for a near-omni pattern
achieves this in respect of circular polarisation so it would be
ineffiecient in a system where a linearly polarised antenna is used at the
other end of the link.

I was once told a true isotropic radiator would have to be circularly
polarised because it would be so small that it could contain nothing with a
defined axis of symmetry ... that is, the antenna would have the form of an
infinitesimal sphere. The question then is 'which sense of circular
polarisation' ... which undoubtedly has nothing at all to do with Coriolis
force! The real answer is that it doesn't matter because, as you mentioned
(below) such an antenna has an infinitesimally small radiation resistance
and cannot be made to radiate.

Chris



Unfortunately, the gain drops, efficiency drops, and feed point
impedance drops, resulting in a rather inferior antenna.

There's also a question of how close to perfection does the spherical
pattern need to become? Within 0.1dB, 1dB, 3dB, etc???? Offhand, I
would guess anything within a few dB of spherical could be considered
isotropic, as in all the patents I noted.

--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

On Sep 4, 9:33*am, Michael Coslo wrote:
Dave wrote:

"Art Unwin" wrote in message
....
On Sep 3, 6:14 pm, "Dave" wrote:
David, you can find the famous "exclusion principle" by Wolfgang Pauli
in any book on Quantum Mechanics.

ah, bringing the Pauli Exclusion Principle in on the discusion now, that
is a new one i think... can we now not have any of your magical
levitating diamagnetic neutrinos on an antenna in the same quantum states??

Drum roll........

*From the department of everything you knew about physics is wrong
department......

The Coriolis effect upon RF radiation has some interesting other
ramifications.
Since Coriolis affects radio waves, it follows that gravity also affects
radio waves. This bring up a new and much simplified explanation for
radio propagation. As the RF spins away from the antenna, the coriolis
effect and gravity eventually pull the signal back to earth far away
from the originating point. I always thought that that silly stuff about
atmospheric layers and ionization was kind of dum anyhow.

Each time the RF hits the earth, a new point of reference is made, and
the signal bounces up with a new twist to it.

We're still working on why UHF + signals don't do this. Maybe their
twist is going the other way, so instead of coming back down, they spin
upwards never to be seen again.

* * * * - 73 de Mike N3LI -

Mike you forget.
I do not subscribe to the wave theory over the particle aproach.
I cannot see any other way to fit that "radiation is from the
acceleration of a charge". And I can not find any explanation of this
in any books. Only mass is able to have spin and at the same time
transport energy, at least to my mind. Therefore accelaration is the
creation of two forces that are not in the same plain ala a shear
action where the combination of gravity and the Coriolis force are the
weakest forces known in the std model. I would remind you that spin is
a result of a force applied where the reaction force is not in the
same plane, otherwise referred to as torque ala force times distance.
It is quite easy to show that current flow consists of a direct vector
and a circular vector
within a boundary and where a direct vector and a circular vector on
the outside of the boundary creats a condition of equilibrium. This is
just physics per our Universe and now many want to deny physics by
intuition alone. I would also remind everybody that engineering,
electrical, mechanical or what ever is a subset of the subject of
physics where concentration of learning is of a niche of the physics .

In article
, Art
Unwin wrote:

It seems that some do not understand what the Corriolis force is so
here goes
When the Big Bang ocurred all energy was in an arbitrary boundary
just like the Sun is. When the forces ( four forces of the Standard
model) could not be contained with in the boundary the boundary broke
which as scientists state was the begining of our Universe. Before the
arbitrary boundary broke it is a state of equilibrium ( This is also
duplicated by the Sun) You can visualize a ball which contains all
energy by placing vectors all around the inside where for every vector
on the inside there is an equal and opposite on the outside. Tho
energy cannot be created or destroyed, kinetic energy can occur at the
expense of potential energy such that the outside vectors are over
come. The boundary breaks and the excess forces are released until
the boundary is able to return to a state of equilibrium. Now when the
break occurs it is at the point of a particular vector such that the
breakage is created by a shearing action, as the forces in question
was not aligned, with spin. Thus when any energy,particles etc they
escaped with a spin action which force forces to balance requires an
equal and opposite reaction and the Corriolis force is that component.
Without the Corriolis component we could not remain on this Earth and
gravity could not exist. Thus to state spin or torque is not a force
is truly rediculous. Let the insults come.

Art,

Since there is no "" on the subject line I assume you are the initiator
of this post and I have to ask how it's relevant to this newsgroup. You
have also attempted to initiate other off-topic threads. Can't you find a
more appropriate ng or forum for these posts rather than show a disregard
for those coming here to seek info on ham antennas and related issues? At
the very least I would appreciate including the standard "OT:" prefix on
the subject lines of off-topic posts. These kinds of posts illustrate why
moderated newsgroups become necessary. Sincerely, and 73s from N4GGO,

John Wood (Code 5550) e-mail:
Naval Research Laboratory
4555 Overlook Avenue, SW
Washington, DC 20375-5337

On Sep 4, 2:49*am, Jeff Liebermann wrote:
On Thu, 3 Sep 2009 21:09:37 -0700 (PDT), Art Unwin

wrote:
You cannot assume that one who makes an accusation has the status of
education to match his veracity. The person who stated that it is an
impossibility does not even posses a high school diploma. Climbing on
the back of his statements puts you back on the stage again!

Hint: *Please feel free to attack a persons ideas, logic, conclusions,
data, information, assertions, assumptions, pontifications, judgment,
and numbers. *This is proper for a technical discussion. *However,
attacking a persons background, education, personality, appearance,
and wallpaper is little better than a character assassination and
should be avoided. *Discuss the ideas, not the person.

That being said, I've learned as much from those without the proper
credentials, than from those with the requisite degrees and
certifications. *Hands on experience and Learn By Destroying(tm) are
amazingly good teachers.

Also, I judge people mostly by their willingness and ability to learn.
When learning stops, one rots in place and eventually withers. *What
have you learned from this discussion on your Gaussian Radiative
Cluster?

--
Jeff Liebermann * *
150 Felker St #D * *http://www.LearnByDestroying.com
Santa Cruz CA 95060http://802.11junk.com
Skype: JeffLiebermann * * AE6KS * *831-336-2558

I replied to the assertion that my homeland was guilty of embarassment
or shame.

What sort of man is one who does not stand up on behalf of his
homeland where presently their soldiers are standing and dying along
side ours of the U.S.
I am attacked personally daily, but to attack the U.K and the
Commonwealth for declaring war on the German menace, a consequence of
which many gave their lives, is a totally different situation to me.
Hopefully you can understand that and thus allow the matter to drop
without loss of stature
Regards
Art