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Old July 11th 06, 01:52 AM posted to rec.radio.amateur.antenna
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Default Quarterwave vertical with radials

Richard Clark wrote:
On Mon, 10 Jul 2006 17:57:42 -0400, John Popelish
wrote:


I meant that half as many photons
are produced, compared to the full dipole antenna that produces the
same fields above the center line.



Hi John,

So, proceeding along your avowed lines of Photons, one of several
questions:
Presuming 100W radiated, how many photons would that be so that we
can talk about them by halves.


Well, you couldn't be radiating 100 watts in both cases if the field
strength is the same above the center line, but half the field is
missing in one of the cases.

But regardless of the radiating structure, if 100 watts at 40 M is
being radiated, you are launching about 2*10^28 photons per second.

Yes, that is perhaps unfair, however it demonstrates how easily the
discussion can tumble for lack of quantifiables such as that original
offering of 100W.


Hence the stipulation that the field strength above the centerline
being constant, rather than the radiated power. I missed that we were
only talking about a case of radiating 100 watts.

Should we discuss how infinitesimal the energy is in a 40M photon?
(Easily accounts for why so many are needed for that same 100W.)


Not much to discuss. I don't do such calculations often, but I get
about 5*10^-27 joule per photon. What do you calculate their energy
to be?

No, I suppose not.


Do you have some point?

Want to get into the problems of diffraction with object lenses that
measure less than a wavelength of the photon?


Sure. That will take us back to how an elevated radial system gives a
different vertical pattern than an actual ground plane or a lossy
ground does. You go first.

Hard to escape, and makes a mess of describing mirrors too, especially
when they are skeletal approximations as well.


You have to start understanding mirrors, somewhere. Perhaps you
prefer a different starting point. There are several.

I can offer more thread-busters when it comes to photonics, but that
is a slam dunk. Get us rolling on one ace proposition, and I will get
back to you in a couple of hours.


I have no idea what you are saying with these two sentences.
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Old July 11th 06, 04:22 PM posted to rec.radio.amateur.antenna
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Default Quarterwave vertical with radials

On Mon, 10 Jul 2006 20:52:38 -0400, John Popelish
wrote:

Not much to discuss. I don't do such calculations often, but I get
about 5*10^-27 joule per photon. What do you calculate their energy
to be?


Hi John,

Closer to 4.63 · 10^-27 joule. Not enough difference to matter. So,
we are talking about a little more than 10^28 photons and when we
return to your statement (or is it twice that?)
I didn't mean that the mirror produces half of the total photons that are radiated.

or
I meant that half as many photons are produced, compared to the
full dipole antenna that produces the same fields above the center line.


I have to again exclaim:

No, I suppose not.


Further, as to your "stipulation:"
the field strength above the centerline
being constant, rather than the radiated power. I missed that we were
only talking about a case of radiating 100 watts.


It would be strange to talk about radiation without some expression of
power to the antenna. 100 watts has been a cardinal value in this
group for many years. Field strength is generally expressed in
volts/meter. Somehow, its translation into eV to follow the photon
metaphor seems rather strained. Going further with this convolution
of centerline partition that relates to same fields (same?) to explain
a difference is also quite odd. Would you care to elaborate on this
concept of the centerline?

Do you have some point?


This is odder yet, you introduce the topic and ask me what my point
is? My own separate observation is the introduction of photonics
doesn't add much does it?

Hard to escape, and makes a mess of describing mirrors too, especially
when they are skeletal approximations as well.


You have to start understanding mirrors, somewhere. Perhaps you
prefer a different starting point. There are several.


Starting with radials would seem to be in keeping with the thread.
Shifting starts when you haven't finished seems to defeat the
progression of where you were going.

I can offer more thread-busters when it comes to photonics, but that
is a slam dunk. Get us rolling on one ace proposition, and I will get
back to you in a couple of hours.


I have no idea what you are saying with these two sentences.


No doubt. I read these same admissions with some frequency. It
rarely keeps me up at nights worrying anymore.

You were going to tie this all together weren't you?

73's
Richard Clark, KB7QHC
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Old July 11th 06, 05:36 PM posted to rec.radio.amateur.antenna
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Default Quarterwave vertical with radials

Richard Clark wrote:
On Mon, 10 Jul 2006 20:52:38 -0400, John Popelish
wrote:

(snip)

I meant that half as many photons are produced, compared to the
full dipole antenna that produces the same fields above the center line.



I have to again exclaim:


No, I suppose not.



Further, as to your "stipulation:"

the field strength above the centerline
being constant, rather than the radiated power. I missed that we were
only talking about a case of radiating 100 watts.



It would be strange to talk about radiation without some expression of
power to the antenna. 100 watts has been a cardinal value in this
group for many years. Field strength is generally expressed in
volts/meter. Somehow, its translation into eV to follow the photon
metaphor seems rather strained. Going further with this convolution
of centerline partition that relates to same fields (same?) to explain
a difference is also quite odd. Would you care to elaborate on this
concept of the centerline?


The center line I am referring to is the mirror line of the ground
plane or radial group that allows a monopole to have a field pattern
(both E and H) above that mirror line, that would exist there, if the
antenna was a symmetrical dipole. Without the mirror effect, the
field pattern of the monopole depends on the path the feed line takes
away from the monopole, and any other conductive objects nearby.

Since I am talking about field patterns, it seemed natural to switch
from total radiated watts to field intensities and the photons that
field emits and where those photons head.

Do you have some point?


I see that you snipped the line of nonsense you originally posted that
prompted this question. You asked,

"Should we discuss how infinitesimal the energy is in a 40M photon?
(Easily accounts for why so many are needed for that same 100W.)

No, I suppose not. "

So I asked if asking a question and dismissing it made some point.

This is odder yet, you introduce the topic and ask me what my point
is? My own separate observation is the introduction of photonics
doesn't add much does it?


While amateurs may ultimately be interested in radiating power in
particular directions, we are discussing the physics of the radiation
process, and photonics is one way to think about that process.

Hard to escape, and makes a mess of describing mirrors too, especially
when they are skeletal approximations as well.


You have to start understanding mirrors, somewhere. Perhaps you
prefer a different starting point. There are several.



Starting with radials would seem to be in keeping with the thread.
Shifting starts when you haven't finished seems to defeat the
progression of where you were going.


The ultimate radial pattern is a solid disk. Once you understand what
that does to the field pattern, you can start toward a radial wire
layer, and see how, in important ways, like the ability to carry
radial current, it resembles a disk. Then, you can explore how
reducing the number of radials alters the approximation.

I can offer more thread-busters when it comes to photonics, but that
is a slam dunk. Get us rolling on one ace proposition, and I will get
back to you in a couple of hours.


I have no idea what you are saying with these two sentences.


No doubt. I read these same admissions with some frequency. It
rarely keeps me up at nights worrying anymore.


I find that unsurprising. Your posts do not seem addressed to me or
others, so much as to yourself.

You were going to tie this all together weren't you?


Probably not, since I am working through the process in my own mind.
I am not the teacher so much as a student trying to learn something
useful. I hope my posts generate more useful discussion from others
than I have gotten from you, so far.
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Old July 12th 06, 02:50 AM posted to rec.radio.amateur.antenna
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Default Quarterwave vertical with radials

On Tue, 11 Jul 2006 12:36:18 -0400, John Popelish
wrote:

The center line I am referring to is the mirror line of the ground
plane or radial group that allows a monopole to have a field pattern
(both E and H) above that mirror line, that would exist there, if the
antenna was a symmetrical dipole. Without the mirror effect, the
field pattern of the monopole depends on the path the feed line takes
away from the monopole, and any other conductive objects nearby.


Hi John,

This is still rather obscure. You are not talking about a line, but
yet another plane. World of difference there, but I won't dispute
semantics further.

Simply raise that monopole, complete with radial plane and the center
line (as you call it), ABOVE the ground plane. I've already analyzed
this elsewhere in conventional jargon, but here it seems Photons offer
a different conclusion. Unfortunately you aren't prepared to pursue
this as you admit later.

The conventional analysis is perfectly capable of dealing with feed
lines or by avoiding them altogether. One can certainly conspire to
fail and corrupt the analysis, so avoiding distractions and placing
the source in the model, at the feedpoint, removes a lot of
uncertainty.

Since I am talking about field patterns, it seemed natural to switch
from total radiated watts to field intensities and the photons that
field emits and where those photons head.


Photons (as any radiation in this case) are incoherent and radiate in
all directions.

While amateurs may ultimately be interested in radiating power in
particular directions, we are discussing the physics of the radiation
process, and photonics is one way to think about that process.


I am perfectly content and competent to that goal.

The ultimate radial pattern is a solid disk. Once you understand what
that does to the field pattern, you can start toward a radial wire
layer, and see how, in important ways, like the ability to carry
radial current, it resembles a disk. Then, you can explore how
reducing the number of radials alters the approximation.


I don't see a photon in this at all.

You were going to tie this all together weren't you?


Probably not, since I am working through the process in my own mind.
I am not the teacher so much as a student trying to learn something
useful. I hope my posts generate more useful discussion from others
than I have gotten from you, so far.


I have, with neutral objectivity, posed issues of diffraction. For
one, the quarterwave antenna, in close proximity to a quarterwave
mirror (those radials), does not present the characteristics of a
point source that might render attractive solutions. Further, even a
point source ray striking a quarterwave mirror suffers considerably.

The long and short of it is that Photons make for an interesting
discussion with regards to antennas. Unfortunately, and as you
obliquely observe about me writing for myself, it seems I'm the only
one willing to carry the topic.

73's
Richard Clark, KB7QHC
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