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#61
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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 |
#62
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![]() "Dan Richardson wrote wrote: What's the matter with 3, equi-spaced radials? Be economical. Save a radial! It looks better too. And there are no arguments about directionality. ---- Reg. Modeling such an arrangement gave no real noticeable difference between using three or four radials. ========================================= Of course it didn't. That's the point I was making. The number of radials, from 1 to N, is immaterial. As N increases there will be a slight improvement in radiating efficiency. The N loss resistances are all in parallel as seen by the feedline. ---- Reg. |
#63
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Tom Donaly wrote:
Besides, you said, yourself, that Cecil is always right. False. Reg didn't say that. -- 73, Cecil http://www.qsl.net/w5dxp |
#64
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On Tue, 11 Jul 2006 11:06:19 -0400, John Popelish
wrote: By the way, I am having second thoughts as to whether or not there should be a 2*pi factor in there, since most physics formulas deal with frequency in radians per second, not cycles per second. But the photon energy formulas usually deal with wavelength, and I have never seen one that assumes a wavelength is a radian of a cycle, rather that a full cycle, so, perhaps Hz is the correct unit. If anyone can clear this up for me, I would appreciate it. Hi John, That would be 2 pi radians per second as frequency - same thing as a cycle. For photonic interactions the classic treatment is usually with wavenumber as frequency not cycles nor radians. However, the 2 pi difference is the difference between the Planck constant represented as h, and its rational equivalent (with 2 pi divided out) of h-bar. 73's Richard Clark, KB7QHC |
#65
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John Popelish wrote:
Cecil Moore wrote: I don't demand agreement, John, just resolution. Resolution in who's mind? In mine, of course. I am obsessive-compulsive that way. Sorry about that - it's probably a character flaw. -- 73, Cecil http://www.qsl.net/w5dxp |
#66
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Reg Edwards wrote:
Of course it didn't. That's the point I was making. The number of radials, from 1 to N, is immaterial. Guess it depends upon one's definition of "immaterial". One horizontal radial will certainly radiate more horizontal radiation than two opposing horizontal radials. -- 73, Cecil http://www.qsl.net/w5dxp |
#67
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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. |
#68
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Cecil Moore wrote:
Tom Donaly wrote: Besides, you said, yourself, that Cecil is always right. False. Reg didn't say that. He said it under his breath as he was writing it to this newsgroup. 73, Tom Donaly, KA6RUH |
#69
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Richard Clark wrote:
On Tue, 11 Jul 2006 11:06:19 -0400, John Popelish wrote: By the way, I am having second thoughts as to whether or not there should be a 2*pi factor in there, since most physics formulas deal with frequency in radians per second, not cycles per second. But the photon energy formulas usually deal with wavelength, and I have never seen one that assumes a wavelength is a radian of a cycle, rather that a full cycle, so, perhaps Hz is the correct unit. If anyone can clear this up for me, I would appreciate it. Hi John, That would be 2 pi radians per second as frequency - same thing as a cycle. For photonic interactions the classic treatment is usually with wavenumber as frequency not cycles nor radians. However, the 2 pi difference is the difference between the Planck constant represented as h, and its rational equivalent (with 2 pi divided out) of h-bar. Thank you. Makes good sense. |
#70
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Cecil Moore wrote:
John Popelish wrote: Cecil Moore wrote: I don't demand agreement, John, just resolution. Resolution in who's mind? In mine, of course. I am obsessive-compulsive that way. Sorry about that - it's probably a character flaw. Then you also probably believe that a character flaw is an absolute, as are and evil. |
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