Reflector mesh surface
 

On Dec 4, 12:14*pm, Cecil Moore wrote:
John Smith wrote:
Cecil Moore wrote:
Rumors are that California is in a different universe.
Guess that "477 ohms" proves it. :-)

Your point being well taken, I can only reply, "477 ohms can ONLY be as
important as the equations which depend upon it to function."

Dang John, you missed the point. In the free space
that exists in my universe in Texas that figure is
376.73031346177... ohms.

Is 477 ohms the Z0 of free space in the land of
fruits and nuts? :-)
--
73, Cecil *http://www.w5dxp.com

"Fruits and Nuts" whow that is really taboo

Reflector mesh surface
 

Art Unwin wrote:

...
John,
my first point was the 477 error but you didn't catch on.No problem
...
My very best regards
Art Unwin KB9MZ.......xg

Yes, both you and Cecil were kind enough to point it out ... hey, what
can I say? I was an idiot and slow on the uptake. I will attempt to be
more observant, but hey, I make such mistakes, now and then ...

Not 477 ohms but 377 ohms, not 477 ohms but 377 ohms ... now, writing
that another 98 times and I may have it! :-)

Regards,
JS

Reflector mesh surface
 

Art Unwin wrote:
"Fruits and Nuts" whow that is really taboo

Not in Texas. :-)
--
73, Cecil http://www.w5dxp.com

Reflector mesh surface
 

Art Unwin wrote:

...
"Fruits and Nuts" whow that is really taboo

You and Cecil, both, have my location in error ... I DON'T live in the
Gay Bay! (i.e., San Francisco) :-)

Personally, I am attempting to get my representatives to sponsor a bill
to give every documented gay person $100,000 to move to Texas!!!! evil
grin

Regards,
JS

Reflector mesh surface
 

Art wrote:
"With inter coupling of elments you only get approximations as the last
element of any array radiates half of that which it receives."

That might be true if the final element in the array is exactly matched
to a load. If the element is lossless and perfectly mismatched, i.e. its
load is a short-circuit, 100% of its received energy can be reradiated.

I choose to respond to Art on this thread and not to start another to
contradict his prior art.

Best regards, Richard Harrison, KB5WZI

Reflector mesh surface
 

John Smith wrote:
You and Cecil, both, have my location in error ... I DON'T live in the
Gay Bay! (i.e., San Francisco) :-)

Yep, when I lived there, the characteristic impedance
of free space was still 377 ohms. :-)

Personally, I am attempting to get my representatives to sponsor a bill
to give every documented gay person $100,000 to move to Texas!!!! evil
grin

The climate in Texas is not very good for gays. Texas
is the only state that still has the legal right to
secede from the Union. Don't be surprised if it happens
under Obama's "rule". One of his transition staff actually
asserted that he would be "READY TO *RULE* FROM DAY ONE".
--
73, Cecil http://www.w5dxp.com

Reflector mesh surface
 

Cecil Moore wrote:

...
The climate in Texas is not very good for gays. Texas
is the only state that still has the legal right to
secede from the Union. Don't be surprised if it happens
under Obama's "rule". One of his transition staff actually
asserted that he would be "READY TO *RULE* FROM DAY ONE".

Don't think that you will be alone. Although, "they" attempt to paint
my state as a bunch of gay-pinko-commies, some of us don't think so ...

However, given the "last eight" and the party which got us here, I am
willing to see what happens first (Bush NEVER lifted a finger to repair
the criminal actions of Clinton--NAFTA is only one example.) And, IMHO,
printing 850 billion dollars and giving it away to those using practices
which got us here in the first place is NO ANSWER ... I'd say the fox
already runs the hen-house.

Keep your finger on the trigger, but don't fire until you see the whites
of their eyes ... :-)

Regards,
JS

Reflector mesh surface
 

Cecil Moore wrote:
John Smith wrote:
You and Cecil, both, have my location in error ... I DON'T live in the
Gay Bay! (i.e., San Francisco) :-)

Yep, when I lived there, the characteristic impedance
of free space was still 377 ohms. :-)

Personally, I am attempting to get my representatives to sponsor a
bill to give every documented gay person $100,000 to move to
Texas!!!! evil grin

The climate in Texas is not very good for gays. Texas
is the only state that still has the legal right to
secede from the Union. Don't be surprised if it happens
under Obama's "rule". One of his transition staff actually
asserted that he would be "READY TO *RULE* FROM DAY ONE".

Texans are too chicken to secede from anything, but it's a nice thought.
If Texas were to secede, the rest of us could say, (stealing from Dr.
Martin Luther King) "Free! Free, at last!"
73,
Tom Donaly, KA6RUH

Reflector mesh surface
 

Art Unwin wrote:

I am aware of that. One person once said the world was round!


Actually most learned people knew the world was round since before
Christ. The circumference was measured to something better than 10%
accuracy using only sticks and shadows.


If one was persuasive enough at the beginninghundred years or so later
if one said
the world was flat he would be called delusional.
If one was very persuasive in the first place he would be rediculed as
it was so obvious to all in the first place.
I hope you get to live another hundred years so that you can meld into
the new crowd of lemmings
Regards
Art

And delusional you are. No doubt about it.

tom
K0TAR

Reflector mesh surface
 

Tom Ring wrote:

...
Actually most learned people knew the world was round since before
Christ. The circumference was measured to something better than 10%
accuracy using only sticks and shadows.

tom
K0TAR

Actually, "sticks and shadows" is nice, for emphasis ... "wells and
shadows" would be a bit more accurate:

http://www.madsci.org/posts/archives...4968.Sh.r.html

Regards,
JS

Reflector mesh surface
 

"Art Unwin" wrote in message
...
Since we are at the low sun cycle I shoose
1" hexigon poultry wire for the mash on my 3 metre dish
At what frequency will there be a noticable effect on aperture
starting with top band?
Many thanks
Art KB9MZ...,XG

where did art go??? i need a good laugh!

Reflector mesh surface
 

Dave wrote:

"Art Unwin" wrote in message
...
Since we are at the low sun cycle I shoose
1" hexigon poultry wire for the mash on my 3 metre dish
At what frequency will there be a noticable effect on aperture
starting with top band?
Many thanks
Art KB9MZ...,XG

where did art go??? i need a good laugh!


Hopefully for treatment.



--
Jim Pennino

Remove .spam.sux to reply.

Reflector mesh surface
 

Dave wrote:

where did art go??? i need a good laugh!


Co-dependent, eh?

- 73 de Mike N3LI -

Reflector mesh surface
 

"Dave" wrote in message
...

"Art Unwin" wrote in message
...
Since we are at the low sun cycle I shoose
1" hexigon poultry wire for the mash on my 3 metre dish
At what frequency will there be a noticable effect on aperture
starting with top band?
Many thanks
Art KB9MZ...,XG

where did art go??? i need a good laugh!

art deco?

mary xmas

Reflector mesh surface
 

On Dec 25, 10:58*am, "KC8QJP" wrote:
"Dave" wrote in message

...

"Art Unwin" wrote in message
...
Since we are at the low sun cycle I shoose
1" hexigon poultry wire for the mash on my 3 metre dish
At what frequency will there be a noticable effect on aperture
starting with top band?
Many thanks
Art KB9MZ...,XG

where did art go??? *i need a good laugh!

art deco?

mary xmas

Update
I have made the dish using 1 inch poultry fencing.
The outline of the dish encloses the backfire antenna i.e. the
antenna finishes at the same datum line
as the periphery of the dish. The reason for this is that I am trying
to obtain a zero plus take off angle or
something less than normal with respect to frequency and height using
a planar design
Placed dish on ground with beam pointing upwards and did a swr graph
from 2 to 20 mhz
Repeated above except dish placed at right angles to earth.
Swr for 14 meg hz rose from 2:1 to 3: 1 but both arrangements followed
the same oscillation of SWR.
Difference probably due to variation in dish efficiency.i.e the first
set up was augmented by the ground surface.,
Haven't added the band frequency selection points as yet.
With the graphed impedance curves being similar I am anticipating a
TOA of around
5 degrees when antenna is raised to around 30 feet
Antenna polarisation is horizontal, verticle and cw cwith respect to
gain polarization all being equal in gain, with total gain
being close to 2.5 db in excess of the other polarizations.
As I stated ,the idea is to lower the TOA from that of a normal planar
design.
Comments welcome as well as thrown rocks and sarcasm. I have modeled
this type of antenna pointing straight up
but not in a horizontal plane which is why I was able to sugest gain
comparables.
Regards
Art

Reflector mesh surface
 

"Art Unwin" wrote in message
...

totally worthless bull snipped

thanks art, i needed that. i'd like to see how you do running qrp in the
stew perry contest this weekend.

Reflector mesh surface
 

On Dec 27, 5:14*am, "Dave" wrote:
"Art Unwin" wrote in message

...

totally worthless bull snipped

thanks art, i needed that. *i'd like to see how you do running qrp in the
stew perry contest this weekend.

Well the idea of 1 inch mesh was a bum idea. I should have kept to my
own thinking.
When transmitters have holes in the casing of 1 inch diameter will be
the time I will use such large holes.
Will now have to take it of and replace with aluminum window mesh.
The present mesh has no idication of working in any sence of the word
Art

Reflector mesh surface
 

"Art Unwin" wrote in message
...

Well the idea of 1 inch mesh was a bum idea. I should have kept to my
own thinking.
When transmitters have holes in the casing of 1 inch diameter will be
the time I will use such large holes.
Will now have to take it of and replace with aluminum window mesh.
The present mesh has no idication of working in any sence of the word
Art

let me give you a hint... its not the mesh that is the problem.

Reflector mesh surface
 

"Dave" wrote in message
...

"Art Unwin" wrote in message
...

Well the idea of 1 inch mesh was a bum idea. I should have kept to my
own thinking.
When transmitters have holes in the casing of 1 inch diameter will be
the time I will use such large holes.
Will now have to take it of and replace with aluminum window mesh.
The present mesh has no idication of working in any sence of the word
Art

let me give you a hint... its not the mesh that is the problem.


The theoretical gain of a dish is expressed as (9.87 times D-squared) /
(wavelength-squared), where D is the dish diameter. If you have a 3 meter
dish and you're working 10m, I calculate the gain as less than unity. Ref:
http://en.wikipedia.org/wiki/Parabolic_antenna

Even then, the efficiency of the dish is assumed to be 100% -- which it
never is. One limitation is the effectiveness of illuminating the entire
surface of the dish uniformly. How can you do that at HF? You need a
compact illuminator at the focal point of the dish but HF doesn't lend
itself to such gyrations.

I think you should not consider a dish for HF. It works only for
wavelengths that are small, compared to the dish size. Don't fight the
math.

Reflector mesh surface
 

"Sal M. Onella" wrote in message
...

"Dave" wrote in message
...

"Art Unwin" wrote in message
...

Well the idea of 1 inch mesh was a bum idea. I should have kept to my
own thinking.
When transmitters have holes in the casing of 1 inch diameter will be
the time I will use such large holes.
Will now have to take it of and replace with aluminum window mesh.
The present mesh has no idication of working in any sence of the word
Art

let me give you a hint... its not the mesh that is the problem.


The theoretical gain of a dish is expressed as (9.87 times D-squared) /
(wavelength-squared), where D is the dish diameter. If you have a 3 meter
dish and you're working 10m, I calculate the gain as less than unity.
Ref:
http://en.wikipedia.org/wiki/Parabolic_antenna

Even then, the efficiency of the dish is assumed to be 100% -- which it
never is. One limitation is the effectiveness of illuminating the entire
surface of the dish uniformly. How can you do that at HF? You need a
compact illuminator at the focal point of the dish but HF doesn't lend
itself to such gyrations.

I think you should not consider a dish for HF. It works only for
wavelengths that are small, compared to the dish size. Don't fight the
math.



what do you get for gain when you use it on 160m like art is doing?

Reflector mesh surface
 

snip

.. *Ref:http://en.wikipedia.org/wiki/Parabolic_antenna

snip

Thank you so much for your input
The URL that you directed me to does not show the restrictions and
assumptions that apply
and we all know that radiation is filled with such things some of
which are not supportable.
A case in point is how reflection is shown upon the belts that
surround the earth which is shown as a curved
like particle rejection where at the same time the URL shows a
straight line reflection.
I do not accept this theory but do accept that a dish is covered with
particles at rest which will repell impinging particles with spin.
I would also point out that the design shown in the URL is based
around an antenna that is broardside where the phase angle comes into
play.
This is distinctly different to a radiator with axial flow that does
not depend on phase change as with planar design reflectors that
evolve solely around inter inductive coupling. As far as the math is
concerned I am starting a a premise that is supported by marthematics
just as one would expand all of Maxwells laws to be solely limited to
those of Ampere where I used an extended Gauss insteas all of which
are based around Newton where the term
(=) is the support for equilibrium or symmetry and where the theory of
radiation of sound and light being of a wave nature is thourouly
debunked in favor of particles.
Never the less your comments are interesting but also symbolic of the
fact that the laws of radiation sghould be thourouly reviewed in the
light of present day findings such that incorrect notions such as the
formation of waves are re examined.
Regards
Art

Reflector mesh surface
 

"Art Unwin" wrote in message
...
I do not accept this theory but do accept that a dish is covered with
particles at rest which will repell impinging particles with spin.

ah yes, don't forget the diamagnetic part... maybe your antenna didn't work
because the wire mesh you used was ferromagnetic instead of diamagnetic so
it didn't have the layer of magical mystery levitating neutrinos. or maybe
you turned it upside down so all the neutrinos ran out of the dish.

Reflector mesh surface
 

On Dec 28, 10:46*am, "Dave" wrote:
"Art Unwin" wrote in message

...

I do not accept this theory but do accept that a dish is covered with
particles at rest which will repell impinging particles with spin.

ah yes, don't forget the diamagnetic part... maybe your antenna didn't work
because the wire mesh you used was ferromagnetic instead of diamagnetic so
it didn't have the layer of magical mystery levitating neutrinos. *or maybe
you turned it upside down so all the neutrinos ran out of the dish.

Let me make this clear once and foir all. Ferromagnetic material
provides for retension of energy via
the hysterysis effect amoung other things. This detracts from energy
required for the Foucault current
which is required for the application of spin to particles. This is
not to say that some vestiges of the
eddy current is not present but it does suggest a typically reduced
radiation field.
As far as a dish reflecter is concerned that has been built around the
necessity of a focal point in the phase changing aproach provided by
inductive interactive elements and does not follow the same aproach
required by the addition of the levitating weak force known as the
Foucalt current
Art

Reflector mesh surface
 

"Art Unwin" wrote in message
...
As far as a dish reflecter is concerned that has been built around the
necessity of a focal point in the phase changing aproach provided by
inductive interactive elements and does not follow the same aproach
required by the addition of the levitating weak force known as the
Foucalt current

ah, so your old theory with the magical levitating diamagnetic neutrinos was
wrong and now you are using a phase change approach (whatever that may be)
and inductive interactions (which i thought you disliked because that is
part of how a Yagi-Uda array works). if the magical levitating diamagnetic
neutrinos is good enough for one antenna, why isn't it good enough for this
one??? or are you admitting you are totally wrong?

Reflector mesh surface
 

On Dec 28, 12:27*pm, "Dave" wrote:
"Art Unwin" wrote in message

...

As far as a dish reflecter is concerned that has been built around the
necessity of a focal point in the phase changing aproach provided by
inductive interactive elements and does not follow the same aproach
required by the addition of the levitating weak force known as the
Foucalt current

ah, so your old theory with the magical levitating diamagnetic neutrinos was
wrong and now you are using a phase change approach (whatever that may be)
and inductive interactions (which i thought you disliked because that is
part of how a Yagi-Uda array works). *if the magical levitating diamagnetic
neutrinos is good enough for one antenna, why isn't it good enough for this
one??? or are you admitting you are totally wrong?

David,
you are building an auguement on sand like "have you stopped beating
your wife?"
You can traverse the world with a steel antenna using less than a watt
with the same message
as a Kw from a huge antenna. The only difference is that one system
provides less samples
of communication for the ear bone requires to decifer. This being
under ideal conditions which are rarely the situation.
I have never disliked the Yagi antenna but I refuse to belief that the
gains enjoyed are absolute because they ignore
the implications of the weak force or eddy currents.They are easily
built. They give close approximations in terms of gain
But the gains supplied do not equate in absolute terms upon which
science rests.
Art

Reflector mesh surface
 

"Art Unwin" wrote in message
...
you are building an auguement on sand like "have you stopped beating
your wife?"

well, have you?

You can traverse the world with a steel antenna using less than a watt
with the same message
as a Kw from a huge antenna. The only difference is that one system
provides less samples
of communication for the ear bone requires to decifer.

now this i must hear... how do you get from steel antennas to samples in the
ear bone? is my ear bone a digital sampler now? does it somehow sample
your magical levitating diamagnetic neutrinos straight out of the aether?
There must be more to this radio stuff than meets the eye if the ear is
involved now! how does that work for transmitting video, does it change how
the eye bone works also?

I have never disliked the Yagi antenna but I refuse to belief that the
gains enjoyed are absolute because they ignore
the implications of the weak force or eddy currents.

you better believe they ignore the weak farce, that is all in your head.

Reflector mesh surface
 

On Dec 28, 1:42*pm, "Dave" wrote:
"Art Unwin" wrote in message

...

you are building an auguement on sand like "have you stopped beating
your wife?"

well, have you?

You can traverse the world with a steel antenna using less than a watt
with the same message
as a Kw from a huge antenna. The only difference is that one system
provides less samples
of communication for the ear bone requires to decifer.

now this i must hear... how do you get from steel antennas to samples in the
ear bone? *is my ear bone a digital sampler now? *does it somehow sample
your magical levitating diamagnetic neutrinos straight out of the aether?
There must be more to this radio stuff than meets the eye if the ear is
involved now! *how does that work for transmitting video, does it change how
the eye bone works also?

I have never disliked the Yagi antenna but I refuse to belief that the
gains enjoyed are absolute because they ignore
the implications of the weak force or eddy currents.

you better believe they ignore the weak farce, that is all in your head.

As a talking head there is no need for you to understand the nuances
of science.
You, like Richard have survived most of your life on unproven data so
I can understand your need to question
whether there is a need for the corrected data that science provides.
This echoes the statement for removing the patent office as "all
possible discoveries have been realized"
Remember what I told you in the past. Free speech is O.K. but the
downside is that it also shows who and what manner of man you actually
are.
From my viewpoint what you have stated so far has only reduced your
credability with respect to radiation and increased the assumption
that you are nothing but a talking head, a trail you started years ago
when denying the feasability of introducing static law with those of
Maxwell where your basis was again just words without scientific
backing.
Art

Reflector mesh surface
 

"Dave" wrote in message
...

"Sal M. Onella" wrote in message
...

"Dave" wrote in message
...

"Art Unwin" wrote in message

...

Well the idea of 1 inch mesh was a bum idea. I should have kept to my
own thinking.
When transmitters have holes in the casing of 1 inch diameter will be
the time I will use such large holes.
Will now have to take it of and replace with aluminum window mesh.
The present mesh has no idication of working in any sence of the word
Art

let me give you a hint... its not the mesh that is the problem.


The theoretical gain of a dish is expressed as (9.87 times D-squared) /
(wavelength-squared), where D is the dish diameter. If you have a 3
meter
dish and you're working 10m, I calculate the gain as less than unity.
Ref:
http://en.wikipedia.org/wiki/Parabolic_antenna

Even then, the efficiency of the dish is assumed to be 100% -- which it
never is. One limitation is the effectiveness of illuminating the
entire
surface of the dish uniformly. How can you do that at HF? You need a
compact illuminator at the focal point of the dish but HF doesn't lend
itself to such gyrations.

I think you should not consider a dish for HF. It works only for
wavelengths that are small, compared to the dish size. Don't fight the
math.



what do you get for gain when you use it on 160m like art is doing?



OK, a 3 meter dish at 160m:

Numerator is 9.87 times 3-squared = 88.83
Denominator is 160-squared = 25600

The quotient is the nominal power gain = 0.00347

In technical terms, this equals a fart in a windstorm.

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

BTW, to validate the formula for a practical dish, plug in the values for
the same 3-meter dish, but use C-band TVRO freqs around 4 GHz. Take the log
of the quotient, multiply by 10 and you get close the customary 40dB gain
associated with those backyard beauties. (I just got rid of mine this year;
the new owner wants to try EME at 1.2 GHz.)

"Sal"
(KD6VKW)

Reflector mesh surface
 

On Dec 30, 12:38*am, "Sal M. Onella"
wrote:
"Dave" wrote in message

...

"Sal M. Onella" wrote in message
...

"Dave" wrote in message
.. .

"Art Unwin" wrote in message

...





Well the idea of 1 inch mesh was a bum idea. I should have kept to my
own thinking.
When transmitters have holes in the casing of 1 inch diameter will be
the time I will use such large holes.
Will now have to take it of and replace with aluminum window mesh.
*The present mesh has no idication of working in any sence of the word
Art

let me give you a hint... its not the mesh that is the problem.

The theoretical gain of a dish is expressed as (9.87 times D-squared) /
(wavelength-squared), where D is the dish diameter. *If you have a 3
meter
dish and you're working 10m, I calculate the gain as less than unity.
Ref:
http://en.wikipedia.org/wiki/Parabolic_antenna

Even then, the efficiency of the dish is assumed to be 100% -- which it
never is. *One limitation is the effectiveness of illuminating the
entire
surface of the dish uniformly. *How can you do that at HF? *You need a
compact illuminator at the focal point of the dish but HF doesn't lend
itself to such gyrations.

I think you should not consider a dish for HF. *It works only for
wavelengths that are small, compared to the dish size. *Don't fight the
math.

what do you get for gain when you use it on 160m like art is doing?

OK, a 3 meter dish at 160m:

Numerator is 9.87 times 3-squared *= *88.83
Denominator is 160-squared *= *25600

The quotient is the nominal power gain *= *0.00347

In technical terms, this equals a fart in a windstorm.

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

BTW, to validate the formula for a practical dish, plug in the values for
the same 3-meter dish, but use C-band TVRO freqs around 4 GHz. Take the log
of the quotient, multiply by 10 and you get close the customary 40dB gain
associated with those backyard beauties. *(I just got rid of mine this year;
the new owner wants to try EME at 1.2 GHz.)

"Sal"
(KD6VKW)

Sal
Are you using formula based on phasing i.e. has a focal point?
If so that is not applicable to CP (circular polarisation) antennas
One is a broardside radiator and the other is a axial or end fire
radiator.
BIG BIG difference. If you study the use of reflectors with helix
antennas you will see that all
reflectors used are straight sided whether as a flat plate, cupped or
as in one instance
conical for the length of the antenna. The parabala is based on inter
inductive coupling
of a dipole so the parabola reflects at maximum current amplitude.,
The helix reflector is not based on
coupling but the true mechanical impact of particles which is vastly
different. It is wonderful when
you use formulas but it is always best to initial perform the
calculation from first principles
to ensure that the formula is applicable where you intend to use it
I have removed my dish and have replaced it with a sheath an aproach
that has already been used for CP
radiators.

Art

Reflector mesh surface
 

On Dec 28, 1:42*pm, "Dave" wrote:
"Art Unwin" wrote in message

...

you are building an auguement on sand like "have you stopped beating
your wife?"

well, have you?

Absolutely not!
I am working from first principles starting with the mathematics of
the Gauss/
Maxwell comparison which was mathematically shown on this newsgroup
by Doctor Davis of M.I.T. provided., This clearly shows the connection
of .
particles as opposed to waves with respect to radiation . This is a
confirming proof of my
aproach I have taken with respect to first principles. Nobody but
nobody has pointed out any error in this aproach.,
For years you have asked for the mathematics and now you have it. If
you can't break the
mathematics then you do not have a platform. It has been quite a
while since the math was provided
and no faults have been provided, the silence has been deafining.
It is because of this finding in my work I am forced to proceed via
first principles since our ancient books
follow a contrary aproach






snip

you better believe they ignore the weak farce, that is all in your head.

The whole world supports the CERN project which costs billions, which
is based on the existence of the four forces. If you are not aware the
weak force is one of the four stated.

Art

Reflector mesh surface
 

"Art Unwin" wrote in message
...

The parabala [sic] is based on inter
inductive coupling
of a dipole so the parabola reflects at maximum current amplitude.

Plane wave reflection from a parabola doesn't have a discrete current
maximum, per se. You are not describing an antenna element whose current is
maximum at the feed point, etc, etc.

The helix reflector is not based on
coupling but the true mechanical impact of particles which is vastly
different.

Maybe true, maybe not. Irrelevant either way. No 160m helix antennas.

... it is always best to initial perform the calculation
from first principles to ensure that the formula is applicable
where you intend to use it.

I did that, it was, and I'm grateful to have your support.

"Sal"

Reflector mesh surface
 

On Dec 30, 9:41*pm, "Sal M. Onella"
wrote:
"Art Unwin" wrote in message

...

The parabala [sic] is based on inter
inductive coupling
of a dipole so the parabola reflects at maximum current amplitude.

Plane wave reflection from a parabola doesn't have a discrete current
maximum, per se. *You are not describing an antenna element whose current is
maximum at the feed point, etc, etc.

That was not my intention. I am pointing to the use of a parabola
reflector as used
with a planar design such as a dipole placed at the focal point to
provide the required phase change
for reflection. ala best possible coupling to achiev e desired effect


The helix reflector is not based on
coupling but the true mechanical impact of particles which is vastly
different.

Maybe true, maybe not. *Irrelevant either way. *No 160m helix antennas.
If you review the works of Kraus and written thesis on different types
of helix
design including the addition of multiple studs you will note that
all reflector surface are linear
and where the sheath style reflector provided maximum gain.
Because of the condensed volume of designs based upon equilibrium
top band frequencies as well as broadcast and below frequences are
available
in a rotatable manner for directivity.
By the way my antenna is based on equilibrium
( how many times have I stated that on this newsgroup?)
which ruled out the standard helical design as it is NOT in
equilibrium




... it is always best to initial perform the calculation
from first principles *to ensure that the formula is applicable
where you intend to use it.

I did that, it was, and I'm grateful to have your support.

Sal
I don't think you did that
The parabolic reflector
is a design to be used in concert with planar designs only.
I used a parabolic initially for temporary experimental purposes only
as I did not find any data of it's use. As cup style reflectors have
proven gain figures for NON planar axial radiation radiators that
would seem
the obvious way to go at the moment



"Sal"
Interesting thoughts tho
Regards
Art