On Mar 31, 7:52 pm, Jim Lux wrote:
wrote:
I find this topic very interesting, including the mandrill part

We all want to have small, broadband, eficient antennas. I believe Art
is right in his original post, today we can have all these
characteristics in the same package. There is no law of physics
forbidding that.

Uhhh. actually there ARE laws of physics putting some pretty severe
constraints on it, if not actually forbidding it, if you also accept the
constraint that the material of which you make the antenna has finite
resistance.

Through advances in computation power we can achieve

today in months what took decades in the past and there is much
research directed at these kinds of new antennas. Eventually
everyone will be able to choose and model his own antenna based on the
characteristics one wants, but without the cumbersome dimensions,
without significant bandwith limitations, without major efficiency
compromises. I believe the tradeoff (for it has to exist one) will be
ease of manufacturing.

Where ease might be defined in terms of being able to be made of
actually realizable materials?



Incidentally these new antennas have a lot to do with what Art
defines as equilibrium although I don't think he has a clear enough
definition. But it's all related to patterns, patterns which can be
found everywhere in nature an which can be expressed almost entirely
through matemathical formulas. Scaling of antennas is clearly
possible, despite of what the Chu-Harrington limit states ( or to be
fair, by applying them in a new way ).

Chu and, later, Harrington said nothing about bandwidth, by the way.
They were more concerned with directivity and size and stored energy
(the latter of which ties to efficiency and bandwidth).

Also, even if you created a very small antenna with high efficiency
(e.g. with superconductors), the fields around such an antenna will be
quite intense, so while the antenna may be small, its near field will be
pretty much the same size as the dipole it replaces, so you'll need to
put that tiny antenna way up in the air with a non-conductive, non-lossy
support to get it away from everything else. Finding a feedline might be
a bit of a challenge. One has to be careful when one draws "the
boundary" of the antenna.

In practical terms, the size of an antenna isn't just the dimensions of
the metal, but the "keepout" area within which you can't tolerate any
intrusions and still keep the same antenna performance (i.e. a 40m
dipole laying on the ground doesn't work nearly as well as a dipole
suspended 10 feet off the ground)

For that matter, avoiding the breakdown of air might be a problem.
Consider a tesla coil, which is basically a fairly inefficient (in terms
of radiated power for RF input power) small antenna for 100 kHz or so.
The limit on performance for the tesla coil isn't thermal heating of the
coil, but HV breakdown. Even a few hundred watts into a "shoebox" sized
coil will have breakdown problems (and this is fully predicted by Chu's
analysis... it's that "energy stored in the field" problem)

I eagerly await the day when the 80 meter dipole will be replace by a
small device the size of a shoe box ( although it might be a bit
larger in the beginning ).

Regards,
Robert

When the air breaks down around an antenna it is because the antenna
is not in a state of equilibrium. When a dipole is replaced by a quad
ala
a series circuit is replaced by a tank circuit it clearly shows that
the latter
is more efficient.This was firmly proven in Quito.Maximum radiation
efficiency requires equilibrium. Period
Art

On Apr 1, 9:18 am, Art Unwin wrote:


When the air breaks down around an antenna it is because the antenna
is not in a state of equilibrium. When a dipole is replaced by a quad
ala
a series circuit is replaced by a tank circuit it clearly shows that
the latter
is more efficient.This was firmly proven in Quito.Maximum radiation
efficiency requires equilibrium. Period
Art

If you don't quit spewing all this blatant horse crap, I will be going
into
talking head mode again.
BTW, I'm younger than you are. So your claims of age affecting
vulnerability to the effects of constant bafflegab and horse caca
will
tested at great lengths in such an endeavor.
The change of the fabled antenna at HCJB had nothing to do with
efficiency. Period.

On Apr 1, 12:57 pm, wrote:
On Apr 1, 9:18 am, Art Unwin wrote:



When the air breaks down around an antenna it is because the antenna
is not in a state of equilibrium. When a dipole is replaced by a quad
ala
a series circuit is replaced by a tank circuit it clearly shows that
the latter
is more efficient.This was firmly proven in Quito.Maximum radiation
efficiency requires equilibrium. Period
Art

If you don't quit spewing all this blatant horse crap, I will be going
into
talking head mode again.
BTW, I'm younger than you are. So your claims of age affecting
vulnerability to the effects of constant bafflegab and horse caca
will
tested at great lengths in such an endeavor.
The change of the fabled antenna at HCJB had nothing to do with
efficiency. Period.

You my friend are a good example of what a redneck thinks.
In the past you have bragged about your lack of schooling
spouting about the times you didn't go to school. Now you have a
license
to operate a radio where you can excercise your freedom of speech at
will.
Unfortunately, as soon as you start vibrating you vocal cords you
instantly
reveal who and what you are. This is of immense inportance to the
rest of us
when considering whether to use our precious time to your utterings.
Go ahead and be a talking head but you will find that your audio lacks
propagation
in the subject of antennas
Have a happy day and be nice to those around you. You will never know
when
that last day of yours comes around despite your youthful age.
Art Unwin

On Apr 1, 12:32 pm, Art Unwin wrote:
On Apr 1, 12:57 pm, wrote:



On Apr 1, 9:18 am, Art Unwin wrote:

When the air breaks down around an antenna it is because the antenna
is not in a state of equilibrium. When a dipole is replaced by a quad
ala
a series circuit is replaced by a tank circuit it clearly shows that
the latter
is more efficient.This was firmly proven in Quito.Maximum radiation
efficiency requires equilibrium. Period
Art

If you don't quit spewing all this blatant horse crap, I will be going
into
talking head mode again.
BTW, I'm younger than you are. So your claims of age affecting
vulnerability to the effects of constant bafflegab and horse caca
will
tested at great lengths in such an endeavor.
The change of the fabled antenna at HCJB had nothing to do with
efficiency. Period.

You my friend are a good example of what a redneck thinks.
In the past you have bragged about your lack of schooling
spouting about the times you didn't go to school. Now you have a
license
to operate a radio where you can excercise your freedom of speech at
will.
Unfortunately, as soon as you start vibrating you vocal cords you
instantly
reveal who and what you are. This is of immense inportance to the
rest of us
when considering whether to use our precious time to your utterings.
Go ahead and be a talking head but you will find that your audio lacks
propagation
in the subject of antennas
Have a happy day and be nice to those around you. You will never know
when
that last day of yours comes around despite your youthful age.
Art Unwin

Prior Art... I have never "bragged" about not going to school.
I was expelled from school. Which means I really didn't have a
whole lot of choice in the matter past that stage.
But in the general scheme of things this means little, as most
schools don't teach antenna theory unless it's a specific college
course.
You have never heard my vocal cords vibrate, as you have never
talked to me. I doubt if you have even heard me on the air.

Being you are so highly educated, why is your spelling
so bad?
Seems to me you went to school, but either slept through
it, or had other things to think about.
In any case, you are the last horses ass that should be
braying about my education.
I educate myself, and have plenty of books laying around.
It's funny, I am self educated and oft speak about antennas,
but few people have any problems with what I write about.
If they do, it's usually some fairly minor detail.
You on the other hand, claim to be well educated, but
almost everything you spout is challenged as bafflegab,
pure untruth, or just plain horse crap.
What is wrong with this picture?
Prior Art, you make me feel gifted, being I seem to be
ahead of you as far as antenna theory, and I didn't
take *any* scholarly courses for it.
I think you should learn to write and spell a little better
if you are going to whine about other peoples lack of
education. Your "Queens English" is a mess.
What is your excuse for this problem?
I absolutely hated English when in school, yet I seem
to be doing a bit better writing it than you, even with my
sub par education. At least I have an excuse though.
Again, you make me feel downright gifted to be on par
with such a highly educated man such as yourself. :/
MK

On Apr 1, 5:15 pm, wrote:
On Apr 1, 12:32 pm, Art Unwin wrote:



On Apr 1, 12:57 pm, wrote:

On Apr 1, 9:18 am, Art Unwin wrote:

When the air breaks down around an antenna it is because the antenna
is not in a state of equilibrium. When a dipole is replaced by a quad
ala
a series circuit is replaced by a tank circuit it clearly shows that
the latter
is more efficient.This was firmly proven in Quito.Maximum radiation
efficiency requires equilibrium. Period
Art

If you don't quit spewing all this blatant horse crap, I will be going
into
talking head mode again.
BTW, I'm younger than you are. So your claims of age affecting
vulnerability to the effects of constant bafflegab and horse caca
will
tested at great lengths in such an endeavor.
The change of the fabled antenna at HCJB had nothing to do with
efficiency. Period.

You my friend are a good example of what a redneck thinks.
In the past you have bragged about your lack of schooling
spouting about the times you didn't go to school. Now you have a
license
to operate a radio where you can excercise your freedom of speech at
will.
Unfortunately, as soon as you start vibrating you vocal cords you
instantly
reveal who and what you are. This is of immense inportance to the
rest of us
when considering whether to use our precious time to your utterings.
Go ahead and be a talking head but you will find that your audio lacks
propagation
in the subject of antennas
Have a happy day and be nice to those around you. You will never know
when
that last day of yours comes around despite your youthful age.
Art Unwin

Prior Art... I have never "bragged" about not going to school.
I was expelled from school. Which means I really didn't have a
whole lot of choice in the matter past that stage.
But in the general scheme of things this means little, as most
schools don't teach antenna theory unless it's a specific college
course.
You have never heard my vocal cords vibrate, as you have never
talked to me. I doubt if you have even heard me on the air.

Being you are so highly educated, why is your spelling
so bad?
Seems to me you went to school, but either slept through
it, or had other things to think about.
In any case, you are the last horses ass that should be
braying about my education.
I educate myself, and have plenty of books laying around.
It's funny, I am self educated and oft speak about antennas,
but few people have any problems with what I write about.
If they do, it's usually some fairly minor detail.
You on the other hand, claim to be well educated, but
almost everything you spout is challenged as bafflegab,
pure untruth, or just plain horse crap.
What is wrong with this picture?
Prior Art, you make me feel gifted, being I seem to be
ahead of you as far as antenna theory, and I didn't
take *any* scholarly courses for it.
I think you should learn to write and spell a little better
if you are going to whine about other peoples lack of
education. Your "Queens English" is a mess.
What is your excuse for this problem?
I absolutely hated English when in school, yet I seem
to be doing a bit better writing it than you, even with my
sub par education. At least I have an excuse though.
Again, you make me feel downright gifted to be on par
with such a highly educated man such as yourself. :/
MK

Pray tell me then why I am incorrect. You can salvage the
answer from your own mind or even from a book.
If you are going to decry my explanation you must have the reason at
your finger tips.
You heard mention of the Tesla coil earlier as a posters sample with
respect to a particular point.
What the poster did not state was that a Tesla coil is NOT in a state
of equilibrium even tho it may be resonant!
Why else would energy break out from a circuit in the form of a spark
if there was more freedom to travel else where?l
Same goes for the old spark plug system, it is not in equilibrium. So
go ahead supply an educated reason
as to why the sparks emminated from the dipole in Quito and why the
closed circuit of a quad pushed the
particular problem away. On the other hand give an educated answer to
the direction of the three vectors
involved in radiation that Harrison cannot give. You say you have
books then go a head with
respect to these two questions that nobody on this group has been able
to resolve.
With all the books you say you have then I would agree with you that
even a high school drop out
can knock hell out of me with respect to antennas.
Have a happy day and smile
Art.
Ps. When younger I passed the Oxford and Cambridge entrance test on
English but old age has taken its toll.

On Apr 2, 1:41 pm, Art Unwin wrote:


Pray tell me then why I am incorrect. You can salvage the
answer from your own mind or even from a book.

When the air breaks down around an antenna it is because the antenna
is not in a state of equilibrium.

Define equilibrium as it pertains to an antenna. Until you do, it's
fairly hard to comment on the first statement.
If you have corona discharge from an antenna, it's usually due
to sharp points when using wire or a whip with a pointed tip.
Thats why they stick round balls on whips, flagpoles, etc..

When a dipole is replaced by a quad ala
a series circuit is replaced by a tank circuit it clearly shows that
the latter is more efficient.

What clearly shows this?
This is the statement which drew my comment.
The efficiency of a 1/2 WL dipole and a 1 WL loop are so close as
to be almost unmeasurable in the real world.
But you can take this even farther. Almost *any* size dipole
or loop will radiate most all of what is fed to it.
A 1/10 WL whip radiates almost all of the power applied to
it, same as a 1/4 WL, 1/2 WL, or whatever you want to try.
This not not conjecture. This is pretty much written in stone
after many years of testing.
Why you continue to ignore this simple fact boggles my mind.
So your statement is so far from reality I would be amiss
in my "talking head" duties if I did not comment.
Don't take my word for it. Ask anyone you can think of
that has a clue. They will tell you the same thing.

What it going to spoil your "full size performance from a
dinky radiator" picnic is not the radiator and it's abilities to be
an efficient radiator.
It's going to be actually feeding the power to such a small
radiator and not turning a large amount of RF to heat in the
process. No cheating letting the feed line be the antenna..
Look at "small" HF transmitting loops. Do you see any
using 22 gauge wire? I doubt it.
They will be using the fattest or widest strip of material
they can get their hands on.
There are other issues involved also in feeding such an
antenna. Never do these small loops equal the performance
of a full size antenna. They radiate enough to maybe let
you operate, and thats about it.



This was firmly proven in Quito.Maximum radiation
efficiency requires equilibrium. Period

Again, the change to quad loops at HCJB was to
avoid the sharp points of the dipoles, yagi's, or
whatever they were using. In the high alitudes of
Quito, HV breakdown at the tips was a serious problem.
The change had absolutely nothing to do with antenna
efficiency.
Not to mention that the whole idea of a loop being
more efficient than a dipole is totally wrong.
And I don't see how equilibrium has anything to
do with it, whatever you might mean by that silly "E"
word.
Anything else you are curious about?
BTW, no grabbing of books were needed to form
this response.
Art

On Apr 2, 10:37 pm, wrote:
On Apr 2, 1:41 pm, Art Unwin wrote:



Pray tell me then why I am incorrect. You can salvage the
answer from your own mind or even from a book.
When the air breaks down around an antenna it is because the antenna
is not in a state of equilibrium.

Define equilibrium as it pertains to an antenna. Until you do, it's
fairly hard to comment on the first statement.

I don't think I can do that for you, it would take to long.

If you have corona discharge from an antenna, it's usually due
to sharp points when using wire or a whip with a pointed tip.
Thats why they stick round balls on whips, flagpoles, etc..

When you have a discharge it is a loss of energy

When a dipole is replaced by a quad ala
a series circuit is replaced by a tank circuit it clearly shows that
the latter is more efficient.

What clearly shows this?
Well there is no discharge. This is becaquse that there is a route
of a lesser impedance available

This is the statement which drew my comment.
The efficiency of a 1/2 WL dipole and a 1 WL loop are so close as
to be almost unmeasurable in the real world.
Almost doesn't count when measuring efficiency and in the real world
many CAN tell the difference
But you can take this even farther. Almost *any* size dipole
or loop will radiate most all of what is fed to it.
Again you are admitting to lower efficiency when you use the word
"most"


A 1/10 WL whip radiates almost all of the power applied to
it, same as a 1/4 WL, 1/2 WL, or whatever you want to try.
This not not conjecture. This is pretty much written in stone
after many years of testing.
Again you use the word "most" which is admitting less efficiency

Why you continue to ignore this simple fact boggles my mind.
So your statement is so far from reality I would be amiss
in my "talking head" duties if I did not comment.
Don't take my word for it. Ask anyone you can think of
that has a clue. They will tell you the same thing.

What it going to spoil your "full size performance from a
dinky radiator" picnic is not the radiator and it's abilities to be
an efficient radiator.
It's going to be actually feeding the power to such a small
radiator and not turning a large amount of RF to heat in the
process. No cheating letting the feed line be the antenna..

I think you are missing the point here. My antenna has a full wave
length of wire
not a fraction there of. So the radiator has the same inductance and
capacitance
that one would expect from a full wave antenna spread out in a
straight line
where the wire surface is exposed to the atmosphere, so there is no
reason
for the energy to circumvent the wire circuit as it must do for a
fractional wavelength.


Look at "small" HF transmitting loops. Do you see any
using 22 gauge wire? I doubt it.
They will be using the fattest or widest strip of material
they can get their hands on.

What you are seeing as representing a loop antenna is a fractional
wave length
Often it comes with a HV variable capacitor for tuning.

The loop that I made was a plastic loop with a full wave length of
wire wound upon it. No high voltage capacitor needed as it coveres
the whole band.
As far as 22 gauge wire being used this is because there is no
mechanical stresses
imposed on it as would be for a stretched out radiator. So the main
consideration
is to supply enough skin depth since the diameter itself
is not a factor in terms of fusing.current

There are other issues involved also in feeding such an
antenna. Never do these small loops equal the performance
of a full size antenna. They radiate enough to maybe let
you operate, and thats about it.

If the scource impedance is one that you can match efficiently
then you have at hand a efficient radiator of a wavelength where
the normal loop you are refering to uses a metal loop as the radiator
which is much shorter than a wavelength of wire wound on a plastic
loop.
The loop is now a small full wave radiator not a small fractional
small wave antenna


This was firmly proven in Quito.Maximum radiation
efficiency requires equilibrium. Period

Again, the change to quad loops at HCJB was to
avoid the sharp points of the dipoles, yagi's, or
whatever they were using. In the high alitudes of
Quito, HV breakdown at the tips was a serious problem.
The change had absolutely nothing to do with antenna
efficiency.
If the impedance is to high on the antenna compared to
discharging through air to the transmitter ground then that
is a very inefficient antenna

Not to mention that the whole idea of a loop being
more efficient than a dipole is totally wrong.
The energy travels easily along the wire circuit without
encountering a high impedance that it is forced to take a circuitous
route thru ground to the transmitter ground. When the energy
is passing thru ground it becomes a loss.

And I don't see how equilibrium has anything to
do with it, whatever you might mean by that silly "E"
word.
If a circuit is not balanced and a fractional wave length long
it is not in equilibrium!. The energy supplied to the radiator
will always encounter a energy wasting impedance in the wire itself if
is not at least a wavelength long, and of the right material
(diamagnetic)
otherwise the energy will seek a route outside the wired circuit which
can only lead to losses. Think of it this way, a fractional wave
length radiator
cannot avoid the energy taking a route thru ground and the ground is a
loss.
Hopefully you now see antennas in a different light. I do urge you to
look up
the tank circuit since it is quite an interesting circuit with its
phase changes
and effective resistances apparently changing without being diverted
from the circuit wire confines. Another place where the books are in
error
is their association with the iron filing magnet experiment at HS
which
forms a magnetic field very different from that formed from aluminum,
copper and other diamagnetic materials. When you pass a time varying
current thru
copper the magnetic field turns at right angles to the radiator axis
and in fact
compliments the electrical field vector ( they are not at right
angles)
Now you can see what lifts or ejects the static particles resting on
the surface
because they are repelled instead of bing magnetically atracted
( Static: nearly devoid of energy and of small mass)
.. So the EH antennas which supposedly combines the EH fields just
didn't
understand that with a radiator the combination of vectors is already
a given!
I think you also are making a mistake that many books make when
referring to
small antennas instead of referring to ELECTRICALLY small antennas

Anything else you are curious about?
BTW, no grabbing of books were needed to form
this response.
Art

Best regards, no offence intended
Art Unwin ......KB9MZ..(uk)