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"Waves of Average Power"
On 29 Oct, 09:32, wrote:
On Oct 29, 8:31 am, art wrote: Cecil, people have stopped calling me a blithering idiot! After a while it gets boring... :/ MK Stick to making loads and top hats for mobile anttenas. You are out of your league on this one Art |
"Waves of Average Power"
On 29 Oct, 08:45, "Dave" wrote:
"art" wrote in message ups.com... On 29 Oct, 08:08, "Dave" wrote: "art" wrote in message roups.com... The DC blast removes the surface particles and in this moment where equilibrium does not exist the static particles are projected beyond the boundary before the boundary shape is repaired. Have you got your mind in the thinking mode yet?Now what does the blast consist of when energy is released nfrom a capacitor bearing in mind that the capacitor plates are made of a diagmatic material? Remember that for this method of deduction all "flux" must pass thru the field so what is it that is stored on the surface plates on the capacitor? Sice some particles are ejected from the field it must bve the same type particles that leave a capacitor where some replace those that are ejected. Art Unwin KB9MZ....XG ah, a blast removes the particles... you know how much of a 'blast' is required to create corona on a wire the way you describe? what electric field strength at the surface of a conductor is required to create that type of breakdown in air? A battery, a flyback transformer etc etc how much in vaccuum? Does not require a vacuum. Remember the old days of spark plug transmissions? define your terms and show all work or you will lose points on the final grade. what happens if i build a capacitor with ferromagnetic material??? does it not work? No what about if I use paramagnetic material? Yes David turn your attention to antenna computor programs When made they made assumptions which is a no, no with laws. The same computor program produces verification of the model! So why not think about whether computor programs are incorrectly based or Maxwells laws has some errors. Start your investigation from a rock hard surface and not sand which has a habit of drifting in time and determine or verify again Maxwells laws and computor programming basics. Is science back to the poll taking days for verification? Stop floundaring and get down to serious thinking since memorising stuff is not getting the job done as it did in college. Art KB9MZ.....XG why should i believe you, you just said that a capacitor with iron plates can't work which is provably wrong. David you have now found something to invest in With the sky rocketing costs of aluminium and copper e.t.c now is the time to get in on ferrite capacitors. Now that you have approved of its use for capacitor you can reap your just rewards your understanding of computer modeling of antennas is similarly flawed.- Hide quoted text - I just buy the commercial programs on the assumption they are not selling me junk. If the results are in accordance with Maxwells laws then that is fineby me. Art KB9MZ......XG - Show quoted text - |
"Waves of Average Power"
"art" wrote in message ups.com... On 29 Oct, 08:45, "Dave" wrote: "art" wrote in message ups.com... On 29 Oct, 08:08, "Dave" wrote: "art" wrote in message roups.com... The DC blast removes the surface particles and in this moment where equilibrium does not exist the static particles are projected beyond the boundary before the boundary shape is repaired. Have you got your mind in the thinking mode yet?Now what does the blast consist of when energy is released nfrom a capacitor bearing in mind that the capacitor plates are made of a diagmatic material? Remember that for this method of deduction all "flux" must pass thru the field so what is it that is stored on the surface plates on the capacitor? Sice some particles are ejected from the field it must bve the same type particles that leave a capacitor where some replace those that are ejected. Art Unwin KB9MZ....XG ah, a blast removes the particles... you know how much of a 'blast' is required to create corona on a wire the way you describe? what electric field strength at the surface of a conductor is required to create that type of breakdown in air? A battery, a flyback transformer etc etc how much in vaccuum? Does not require a vacuum. Remember the old days of spark plug transmissions? define your terms and show all work or you will lose points on the final grade. what happens if i build a capacitor with ferromagnetic material??? does it not work? No what about if I use paramagnetic material? Yes David turn your attention to antenna computor programs When made they made assumptions which is a no, no with laws. The same computor program produces verification of the model! So why not think about whether computor programs are incorrectly based or Maxwells laws has some errors. Start your investigation from a rock hard surface and not sand which has a habit of drifting in time and determine or verify again Maxwells laws and computor programming basics. Is science back to the poll taking days for verification? Stop floundaring and get down to serious thinking since memorising stuff is not getting the job done as it did in college. Art KB9MZ.....XG why should i believe you, you just said that a capacitor with iron plates can't work which is provably wrong. David you have now found something to invest in With the sky rocketing costs of aluminium and copper e.t.c now is the time to get in on ferrite capacitors. Now that you have approved of its use for capacitor you can reap your just rewards your understanding of computer modeling of antennas is similarly flawed.- Hide quoted text - I just buy the commercial programs on the assumption they are not selling me junk. If the results are in accordance with Maxwells laws then that is fineby me. Art KB9MZ......XG - Show quoted text - ok, so where in maxwells laws does the magnetic properties of the capacitor plates affect how it works? |
"Waves of Average Power"
On Oct 29, 11:20 am, art wrote:
On 29 Oct, 09:32, wrote: On Oct 29, 8:31 am, art wrote: Cecil, people have stopped calling me a blithering idiot! After a while it gets boring... :/ MK Stick to making loads and top hats for mobile anttenas. You are out of your league on this one Art You got that right... :/ MK |
"Waves of Average Power"
On 29 Oct, 11:10, "Dave" wrote:
"art" wrote in message ups.com... On 29 Oct, 08:45, "Dave" wrote: "art" wrote in message roups.com... On 29 Oct, 08:08, "Dave" wrote: "art" wrote in message roups.com... The DC blast removes the surface particles and in this moment where equilibrium does not exist the static particles are projected beyond the boundary before the boundary shape is repaired. Have you got your mind in the thinking mode yet?Now what does the blast consist of when energy is released nfrom a capacitor bearing in mind that the capacitor plates are made of a diagmatic material? Remember that for this method of deduction all "flux" must pass thru the field so what is it that is stored on the surface plates on the capacitor? Sice some particles are ejected from the field it must bve the same type particles that leave a capacitor where some replace those that are ejected. Art Unwin KB9MZ....XG ah, a blast removes the particles... you know how much of a 'blast' is required to create corona on a wire the way you describe? what electric field strength at the surface of a conductor is required to create that type of breakdown in air? A battery, a flyback transformer etc etc how much in vaccuum? Does not require a vacuum. Remember the old days of spark plug transmissions? define your terms and show all work or you will lose points on the final grade. what happens if i build a capacitor with ferromagnetic material??? does it not work? No what about if I use paramagnetic material? Yes David turn your attention to antenna computor programs When made they made assumptions which is a no, no with laws. The same computor program produces verification of the model! So why not think about whether computor programs are incorrectly based or Maxwells laws has some errors. Start your investigation from a rock hard surface and not sand which has a habit of drifting in time and determine or verify again Maxwells laws and computor programming basics. Is science back to the poll taking days for verification? Stop floundaring and get down to serious thinking since memorising stuff is not getting the job done as it did in college. Art KB9MZ.....XG why should i believe you, you just said that a capacitor with iron plates can't work which is provably wrong. David you have now found something to invest in With the sky rocketing costs of aluminium and copper e.t.c now is the time to get in on ferrite capacitors. Now that you have approved of its use for capacitor you can reap your just rewards your understanding of computer modeling of antennas is similarly flawed.- Hide quoted text - I just buy the commercial programs on the assumption they are not selling me junk. If the results are in accordance with Maxwells laws then that is fineby me. Art KB9MZ......XG - Show quoted text - ok, so where in maxwells laws does the magnetic properties of the capacitor plates affect how it works?- Hide quoted text - - Show quoted text - David, Your questions go on and on as if you have never taken physics! To get up to speed you need to take some classes and maybe ask your lecturer some of the questions that you are asking of me. Until then start a business making ferrite capacitors which you say work instead of high priced aluminum. Perhaps start an IPO and get your money up front since you have proof you can make it work.Why not join your buddy KB9.... and get on his thread then overnight you will become an expert, relative that is to those that you join Art Unwin KB9MZ...xg |
"Waves of Average Power"
"art" wrote (but not to me):
Your questions go on and on as if you have never taken physics! To get up to speed you need to take some classes and maybe ask your lecturer some of the questions that you are asking of me. __________ Art -- If you believe that either physics or accumulated field experience supports your belief that "efficient" antennas need to be "tank circuits" where "The DC blast removes the surface particles and in this moment where equilibrium does not exist the static particles are projected beyond the boundary before the boundary shape is repaired," etc etc, then please post proven mathematical support for your concepts -- whether your own, or that of others. Your intuition alone is not sufficient. And if you can't, then would you not agree that you should NOT be posting such concepts as proven reality, whilst abusing others who doubt and/or ask for proof of your concepts, and misleading those who might believe what you post, without proof of its accuracy? RF |
"Waves of Average Power"
On 29 Oct, 15:10, "Richard Fry" wrote:
"art" wrote (but not to me): Your questions go on and on as if you have never taken physics! To get up to speed you need to take some classes and maybe ask your lecturer some of the questions that you are asking of me. __________ Art -- If you believe that either physics or accumulated field experience supports your belief that "efficient" antennas need to be "tank circuits" where "The DC blast removes the surface particles and in this moment where equilibrium does not exist the static particles are projected beyond the boundary before the boundary shape is repaired," etc etc, then please post proven mathematical support for your concepts -- whether your own, or that of others. Your intuition alone is not sufficient. And if you can't, then would you not agree that you should NOT be posting such concepts as proven reality, whilst abusing others who doubt and/or ask for proof of your concepts, and misleading those who might believe what you post, without proof of its accuracy? RF Just read the archives to get what you want instead of getting personal attention. I am certainly not going to start at the beginning again just for you. The mathematical support is all there. If you don't understand the math then you should not jump to conclusions about who is misleading who. Just get off my back . |
"Waves of Average Power"
"art" wrote
in message ups.com... Just read the archives to get what you want instead of getting personal attention. I am certainly not going to start at the beginning again just for you. The mathematical support is all there. _________ Wrong. I've read your archives. The mathematical PROOFS of the beliefs you espouse are not to be found or linked there -- either from your direct efforts, or those of any other source. RF |
"Waves of Average Power"
"art" wrote in message oups.com... David, Your questions go on and on as if you have never taken physics! To get up to speed you need to take some classes and maybe ask your lecturer some of the questions that you are asking of me. Until then start a business making ferrite capacitors which you say work instead of high priced aluminum. Perhaps start an IPO and get your money up front since you have proof you can make it work.Why not join your buddy KB9.... and get on his thread then overnight you will become an expert, relative that is to those that you join Art Unwin KB9MZ...xg again you show your ignorance and try to twist words... i said nothing about 'ferrite' in capacitors, i asked you how to explain why ferromagnetic material as capacitor plates wouldn't work, then asked for the equation reference to show where that effect existed in maxwells laws... which you like to say are correct, but then insist on adding other effects to them that aren't needed nor correct. |
"Waves of Average Power"
On 29 Oct, 20:00, "Stefan Wolfe" wrote:
"art" wrote in message oups.com... On 28 Oct, 20:03, "Stefan Wolfe" wrote: Please take note that Maxwells equations verify this model I suggest you look up in the archives my research on Gauss since you are new to the group before you next want to invalidate Maxwell!! Regards Art Art, I am not certain *physically* as to what happens when the RF energy, stored as AC discreet electrons in your tank circuit, is converted to the RF wave/photon energy in the EM wave emitted from your antenna. Maxwell describes "what" happens, not physically "how" it happens. You claim to describe physically "how" it happens and claim that your theory does not disagree with Maxwell. I can say that a supreme being from Xenu causes a rock to fall when I drop it from a cliff and that may not conflict with Newton. But the emission of electrons from any antenna of whatever magnetic properties, assuming it is even a conductor, does not meet basic science unless you are referring to corona which we are not. You have probably read that one can even construct a crude transmitter by rubbing a ping-pong ball on a carpet to induce a static charge on it and then move the resulting E-field it up and down. In that case we have a non-magnetic/non-metallic antenna producing an ELF EM radiowave of about 30 millions meters in wavelength. I do know that EM waves are composed of fields, not discreet electrons moving in space (whether we describe the phenomenon in terms of waves or photons). In response to your post, Maxwells equations are all about *fields*. These EM fields move at the speed of light. Electrons do not move at c. They cannot; it is physically improssible as you know. The electrons involved in creating the EM field are hardly even displaced along the length/surface of your antenna. I submit that, when your equipment generates an EM wave, the finite number of electrons that your tank circuit can hold, although extremely high, can in no way begin to approach the infinite number of receiving "antennas" (much less the number of "electrons" they could each "receive") in the whole universe that can and do receive your signal. You have said a lot but it appears that for what ever reason you reject what I submit. So I give you one morsel to ponder upon. When you apply a time vary field to a gaussian static field the result is an equation that matches Maxwell( read archives for the discussion on that) Since static particles are in no way in planar form but it still conforms to Maxwell one should be able to insert into a antenna computor program with an optimiser a radiator of some length at an angle to the earths surface and ask for max vertical or horizontal gain. I did that and gave the optimizer response to this group for verification by any computor program they want to use. It was verified using NEC 4 and is in the archives. So disregarding any "how radiation works" I will leave you and anybody else to explain 1 When a time varying field is applied to a static field the resultant equation is the same as Maxwells 2 when a non planar radiator as in a static field is inserted in a program based on Maxwell's laws it produces a result that is not planar and verified by other antenna programs. I welcome any response that explains why such a thing could happen using established theory. Forget the hand waving and address those two basic statements in a scietific manner. For starters, all of this group stated that you cannot add time to both sides of the static equation which put them all in opposition to anything that followed, despite intervention from a Doctor at MIT showing that I was correct in detailed mathematical form Why? Well it is just because...........no reasons given, just because. Your move Art Unwin KB9MZ.....XG |
"Waves of Average Power"
Christopher Cox wrote:
That would make a Yagi's behavior somewhat laser like. Photons would excite a Yagi's element which would then eventually emit its own photon. I wonder if the excited photon would be emitted in the same plane as the received one.......Nahhhhh. The energized electrons in the driven element emit coherent photons some of which are absorbed by electrons in the the parasitic elements. The energized electrons in the parasitic elements emit more coherent photons, some in phase and some out of phase with the driven element photons. Coherent photons interfere destructively in some places and constructively in other places. The result is the radiation pattern of the antenna. -- 73, Cecil http://www.w5dxp.com |
"Waves of Average Power"
Cecil Moore wrote:
Coherent photons interfere destructively in some places and constructively in other places. What can you tell us of the incoherent ones? :-) 73, ac6xg |
"Waves of Average Power"
"Cecil Moore" wrote in message
... Christopher Cox wrote: That would make a Yagi's behavior somewhat laser like. Photons would excite a Yagi's element which would then eventually emit its own photon. I wonder if the excited photon would be emitted in the same plane as the received one.......Nahhhhh. The energized electrons in the driven element emit coherent photons some of which are absorbed by electrons in the the parasitic elements. The energized electrons in the parasitic elements emit more coherent photons, some in phase and some out of phase with the driven element photons. Coherent photons interfere destructively in some places and constructively in other places. The result is the radiation pattern of the antenna. -- 73, Cecil http://www.w5dxp.com "coherent photons" It's a laser? Cool. |
"Waves of Average Power"
On Oct 30, 10:00 am, Jim Kelley wrote:
Cecil Moore wrote: Coherent photons interfere destructively in some places and constructively in other places. What can you tell us of the incoherent ones? :-) 73, ac6xg You mean the ones that have had too much cheap rum? Wait till the next day and ask them when they have a throbbing hangover. One advantage, at typical ham frequencies, is that you'll have plenty of them, though you may have a hard time distinguishing one from another. |
"Waves of Average Power"
K7ITM wrote: On Oct 30, 10:00 am, Jim Kelley wrote: Cecil Moore wrote: Coherent photons interfere destructively in some places and constructively in other places. What can you tell us of the incoherent ones? :-) 73, ac6xg You mean the ones that have had too much cheap rum? Wait till the next day and ask them when they have a throbbing hangover. One advantage, at typical ham frequencies, is that you'll have plenty of them, though you may have a hard time distinguishing one from another. It's photobigotry. That's why those coherent ones gotta 'stick together'. :-) 73, ac6xg |
"Waves of Average Power"
Jim Kelley wrote:
Cecil Moore wrote: Coherent photons interfere destructively in some places and constructively in other places. What can you tell us of the incoherent ones? :-) They are a lot like physics professors, i.e. hard to understand? :-) As far as RF goes, photons from a single source are considered to be coherent with each other but not coherent with any other photons. Photons can only interfere with other photons with which they are coherent. For two incoherent light waves, the irradiance equation is Itotal = I1 + I2, i.e. no interference term. For two coherent waves, the irradiance equation is Itotal = I1 + I2 + 2*SQRT(I1*I2)cos(A). The extra term in the coherent irradiance equation is the *interference term* where A is the phase angle between the fields. Have you figured out where the physical objects are around a free-space dipole that cause the radiation interference patterns? -- 73, Cecil http://www.w5dxp.com |
"Waves of Average Power"
H. Adam Stevens wrote:
"coherent photons" It's a laser? Cool. Surprise! Our $100 RF transmitters emit coherent photons just like a $100,000 laser. Maybe we should call them RASERs. :-) Do you remember MASERs? -- 73, Cecil http://www.w5dxp.com |
"Waves of Average Power"
Christopher Cox wrote:
Thinking from my "Imagination", it would be cool to find a way to "pump" the parasitic element to emit a companion photon much like the one emitted from a atom in a lasing medium. Are there any orbital electron energy step functions that match RF frequencies? -- 73, Cecil http://www.w5dxp.com |
"Waves of Average Power"
Cecil Moore wrote:
Have you figured out where the physical objects are around a free-space dipole that cause the radiation interference patterns? Can't say that I have. If it's not a physical object and yet it can be used to radiate electromagnetic waves, I'll have to rely on you to explain how it works. 73, ac6xg |
"Waves of Average Power"
Jim Kelley wrote:
Cecil Moore wrote: Have you figured out where the physical objects are around a free-space dipole that cause the radiation interference patterns? Can't say that I have. If it's not a physical object and yet it can be used to radiate electromagnetic waves, I'll have to rely on you to explain how it works. You didn't answer my simple question on another thread. The question is: Can interference occur in free space devoid of any of your required physical objects? Example: Given a cubic meter of free space containing no physical objects. Can interference occur within that space? Your earlier posting implied that interference could not occur in free space devoid of physical objects. -- 73, Cecil http://www.w5dxp.com |
"Waves of Average Power"
Cecil Moore wrote: You didn't answer my simple question on another thread. I don't want to get in another silly fight with you, Cecil. I'm evacuated from my house right now, and don't have a lot of patience to expend. The question is: Can interference occur in free space devoid of any of your required physical objects? Not from one source of light without any physical objects to act as a reflecting surface. 73, ac6xg |
"Waves of Average Power"
Jim Kelley wrote:
I'm evacuated from my house right now, and don't have a lot of patience to expend. I assume that is the result of the fire storm out there in CA. The whole nation is praying for you guys. When does the wet season start? Not from one source of light without any physical objects to act as a reflecting surface. Can the physical objects be outside of the cubic meter of space that is under consideration? If so, I misunderstood your earlier posting. (If you say "yes" they could be light-years outside the cubic meter under consideration.) -- 73, Cecil http://www.w5dxp.com |
"Waves of Average Power"
Cecil Moore wrote:
Jim Kelley wrote: I'm evacuated from my house right now, and don't have a lot of patience to expend. I assume that is the result of the fire storm out there in CA. The whole nation is praying for you guys. When does the wet season start? Generally, never. We had 3 inches of rain last year. Soon though, Diane Feinstein and Barbara Boxer will introduce punitive legislation making it more difficult for people to live in (arid regions of) Southern California - ostensibly to save Snail Darters in the Sacramento delta. It's a kind of inedible fish I think. Not from one source of light without any physical objects to act as a reflecting surface. Can the physical objects be outside of the cubic meter of space that is under consideration? If so, I misunderstood your earlier posting. (If you say "yes" they could be light-years outside the cubic meter under consideration.) I don't think it matters where it is, or how much space is involved. For a single source to create an interferernce pattern, there must be a reflector somewhere. An antenna tuner for example. Interference is the result of the overlap of waves. 73, ac6xg |
"Waves of Average Power"
Jim Kelley wrote in news:fg8c3e$kbc$1
@news.service.uci.edu: I don't think it matters where it is, or how much space is involved. For a single source to create an interferernce pattern, there must be a reflector somewhere. An antenna tuner for example. Interference is the result of the overlap of waves. Jim, could a diffractor or refractor provide the physical device that might lead to interference? Owen |
"Waves of Average Power"
Owen Duffy wrote: Jim Kelley wrote in news:fg8c3e$kbc$1 @news.service.uci.edu: I don't think it matters where it is, or how much space is involved. For a single source to create an interferernce pattern, there must be a reflector somewhere. An antenna tuner for example. Interference is the result of the overlap of waves. Jim, could a diffractor or refractor provide the physical device that might lead to interference? Owen I'm am almost certain that you already know the answer to that question, so I'm left to wonder why you are asking it. Jim |
"Waves of Average Power"
Jim Kelley wrote in
: Owen Duffy wrote: Jim Kelley wrote in news:fg8c3e$kbc$1 @news.service.uci.edu: I don't think it matters where it is, or how much space is involved. For a single source to create an interferernce pattern, there must be a reflector somewhere. An antenna tuner for example. Interference is the result of the overlap of waves. Jim, could a diffractor or refractor provide the physical device that might lead to interference? Owen I'm am almost certain that you already know the answer to that question, so I'm left to wonder why you are asking it. No, I am not certain, and in the interest of learning from you I am questioning the generality of whether a reflector is the only means of creating interference from a single source. Owen |
"Waves of Average Power"
Stefan Wolfe wrote:
I see no other means this energy can be imparted other then via electrons (ON AVERAGE) exchanging orbital states in the antenna copper (etc.) atoms resulting in a release of this total energy per photon. How can photons otherwise be manufactured by passing an analog wavelike-field forcing function through another field? Above you are referring to tight-binding electrons. But Our RF antennas make use of *free electrons* which are thought to exist in the outer orbits of conductors. Instead of changing orbits within a single atom, these free electrons jump from atom to atom and from groups of atoms to other groups of atoms. When a free electron emits a photon, it is not associated with an orbit change and so is not quantized to any orbit change. The photon is instead quantized to the frequency of the energy source and is therefore coherent with that source which is our RF transmitters. -- 73, Cecil http://www.w5dxp.com |
"Waves of Average Power"
Jim Kelley wrote:
I don't think it matters where it is, or how much space is involved. For a single source to create an interferernce pattern, there must be a reflector somewhere. An antenna tuner for example. Interference is the result of the overlap of waves. Do you consider a dipole in free space to be a "single source"? There is no reflector yet there is plenty of interference. -- 73, Cecil http://www.w5dxp.com |
"Waves of Average Power"
"Cecil Moore" wrote in message . net... H. Adam Stevens wrote: "coherent photons" It's a laser? Cool. Surprise! Our $100 RF transmitters emit coherent photons just like a $100,000 laser. Maybe we should call them RASERs. :-) Do you remember MASERs? -- 73, Cecil http://www.w5dxp.com "transmitters emit coherent photons " Sure Cecil. And the laser pointer I use was a bit less expensive. MASER: Microwave Amplification by Stimulated Emission of Radiation "The fundamental physical principle motivating the MASER is the concept of stimulated emission, first introduced by Einstein in 1917. Before defining it we look at two related but more familiar phenomena involving the interplay between matter and radiation, absorption and spontaneous emission." http://einstein.stanford.edu/content/faqs/maser.html "MASER. In each frame, a molecule in the upper level of the MASER transition (that is, in the high energy, excited state) is indicated by a large red circle, while one in the lower level (low energy state) is indicated by a small blue circle. (a) All of the molecules are in the upper state and a photon of wavelength l (shown in green) is incident from the left. (b) The photon l stimulates emission from the first molecule, so there are now two photons of wavelength l, in phase. (c) These photons stimulate emission from the next two molecules, resulting in four photons of wavelength l. (d) The process continues with another doubling of the number of photons." Stimulated Emission of Radiation is a quantum mechanical effect that has exactly zero to do with HF radio. For microwaves we use molecules, for light we use atoms. 73 H. NQ5H "Waves of average nausea" is more like it. |
"Waves of Average Power"
Owen Duffy wrote: Jim Kelley wrote in : Owen Duffy wrote: Jim Kelley wrote in news:fg8c3e$kbc$1 : I don't think it matters where it is, or how much space is involved. For a single source to create an interferernce pattern, there must be a reflector somewhere. An antenna tuner for example. Interference is the result of the overlap of waves. Jim, could a diffractor or refractor provide the physical device that might lead to interference? Owen I am almost certain that you already know the answer to that question, so I'm left to wonder why you are asking it. No, I am not certain, and in the interest of learning from you I am questioning the generality of whether a reflector is the only means of creating interference from a single source. Owen Fair enough, Owen. The easiest way I can think of to demonstate interference of light is with a laser and a pair of narrow, closely spaced slits. A diffration grating is essentially an array of slit-like reflectors that generates a more complex type of interference pattern. You could use one of the internal surfaces of a prism (refractor) as a reflector. Partially reflective beam splitters or mirrors are often used in interfereometers. And there are of course methods by which to create sonic interference. The simplest way is to wire a pair of stereo speakers out of phase and observe the frequency dependent phase cancellation effect by listening to music at different positions and speaker separations. There are any number of possible ways to generate interference phenomena, all of which utilize real physical objects to redirect radiation. It is the real physical objects used to create the interference pattern that redirect energy. 73, ac6xg |
"Waves of Average Power"
Cecil Moore wrote: Jim Kelley wrote: I don't think it matters where it is, or how much space is involved. For a single source to create an interferernce pattern, there must be a reflector somewhere. An antenna tuner for example. Interference is the result of the overlap of waves. Do you consider a dipole in free space to be a "single source"? There is no reflector yet there is plenty of interference. If there is no reflector and no splitter to redirect a portion of the ratiated energy, but an interference pattern still results, then there must be more than a single source. It should be fairly obvious that both parts of the antenna must be present in order to generate the dipole-type interference pattern. 73, ac6xg |
"Waves of Average Power"
On Oct 31, 12:08 pm, Jim Kelley wrote:
Owen Duffy wrote: Jim Kelley wrote in : Owen Duffy wrote: Jim Kelley wrote in news:fg8c3e$kbc$1 : I don't think it matters where it is, or how much space is involved. For a single source to create an interferernce pattern, there must be a reflector somewhere. An antenna tuner for example. Interference is the result of the overlap of waves. Jim, could a diffractor or refractor provide the physical device that might lead to interference? Owen I am almost certain that you already know the answer to that question, so I'm left to wonder why you are asking it. No, I am not certain, and in the interest of learning from you I am questioning the generality of whether a reflector is the only means of creating interference from a single source. Owen Fair enough, Owen. The easiest way I can think of to demonstate interference of light is with a laser and a pair of narrow, closely spaced slits. A diffration grating is essentially an array of slit-like reflectors that generates a more complex type of interference pattern. You could use one of the internal surfaces of a prism (refractor) as a reflector. Partially reflective beam splitters or mirrors are often used in interfereometers. And there are of course methods by which to create sonic interference. The simplest way is to wire a pair of stereo speakers out of phase and observe the frequency dependent phase cancellation effect by listening to music at different positions and speaker separations. There are any number of possible ways to generate interference phenomena, all of which utilize real physical objects to redirect radiation. It is the real physical objects used to create the interference pattern that redirect energy. 73, ac6xg You can also use pure refraction--for example through multiple prisms whose output face is not parallel with the input face, to bend the light around as many total degrees as you wish (barring attenuation in the prism). You can also bend the light away, and then back, to get a displacement. But I suppose in all these, the effect depends on waves coming from what appear to be different points in space. Of course, it does not require coherent sources to see the effects of interference. Interference is an instantaneous effect, and you can take the average over a single cycle to see the power. So even with sources on slightly different frequencies, it's easy to see the pattern. However, with different frequencies, the pattern is ever- changing, repeating when the sources are all back to the starting phase. As H.A.S. says, "waves of average nausea" or maybe it's becoming intense nausea. Are we sea-sick yet? Or just sick and tired of it. Cheers, Tom |
"Waves of Average Power"
Jim Kelley wrote:
Do you consider a dipole in free space to be a "single source"? There is no reflector yet there is plenty of interference. If there is no reflector and no splitter to redirect a portion of the ratiated energy, but an interference pattern still results, then there must be more than a single source. It should be fairly obvious that both parts of the antenna must be present in order to generate the dipole-type interference pattern. Just trying to understand - are you considering the two sections of dipole to be two separate sources? -- 73, Cecil http://www.w5dxp.com |
"Waves of Average Power"
K7ITM wrote:
Of course, it does not require coherent sources to see the effects of interference. True, but it does require coherent waves to accomplish the permanent wave cancellation described at: micro.magnet.fsu.edu/primer/java/scienceopticsu/interference/waveinteractions/index.html "... when two waves of equal amplitude and wavelength that are 180-degrees ... out of phase with each other meet, they are not actually annihilated, ... All of the photon energy present in these waves must somehow be recovered or redistributed in a new direction, according to the law of energy conservation ... Instead, upon meeting, the photons are redistributed to regions that permit constructive interference, so the effect should be considered as a redistribution of light waves and photon energy rather than the spontaneous construction or destruction of light." This is what happens to the reflected waves at a Z0-match in a transmission line. -- 73, Cecil http://www.w5dxp.com |
"Waves of Average Power"
K7ITM wrote: On Oct 31, 12:08 pm, Jim Kelley wrote: Owen Duffy wrote: Jim Kelley wrote in : Owen Duffy wrote: Jim Kelley wrote in news:fg8c3e$kbc$1 : I don't think it matters where it is, or how much space is involved. For a single source to create an interferernce pattern, there must be a reflector somewhere. An antenna tuner for example. Interference is the result of the overlap of waves. Jim, could a diffractor or refractor provide the physical device that might lead to interference? Owen I am almost certain that you already know the answer to that question, so I'm left to wonder why you are asking it. No, I am not certain, and in the interest of learning from you I am questioning the generality of whether a reflector is the only means of creating interference from a single source. Owen Fair enough, Owen. The easiest way I can think of to demonstate interference of light is with a laser and a pair of narrow, closely spaced slits. A diffration grating is essentially an array of slit-like reflectors that generates a more complex type of interference pattern. You could use one of the internal surfaces of a prism (refractor) as a reflector. Partially reflective beam splitters or mirrors are often used in interfereometers. And there are of course methods by which to create sonic interference. The simplest way is to wire a pair of stereo speakers out of phase and observe the frequency dependent phase cancellation effect by listening to music at different positions and speaker separations. There are any number of possible ways to generate interference phenomena, all of which utilize real physical objects to redirect radiation. It is the real physical objects used to create the interference pattern that redirect energy. 73, ac6xg You can also use pure refraction--for example through multiple prisms whose output face is not parallel with the input face, to bend the light around as many total degrees as you wish (barring attenuation in the prism). You can also bend the light away, and then back, to get a displacement. But I suppose in all these, the effect depends on waves coming from what appear to be different points in space. Of course, it does not require coherent sources to see the effects of interference. Interference is an instantaneous effect, and you can take the average over a single cycle to see the power. So even with sources on slightly different frequencies, it's easy to see the pattern. However, with different frequencies, the pattern is ever- changing, repeating when the sources are all back to the starting phase. As H.A.S. says, "waves of average nausea" or maybe it's becoming intense nausea. Are we sea-sick yet? Or just sick and tired of it. Yes, in the future we should try to better refinine our generalizations to include any means which can be used to redirect one or more paths of radiated energy (not including particles with rest mass greater than zero) in such a way as to be coincident at some point in space. Lest we allow ourselves to stray too far from it, the only point attempting to be noticed here is that all such means must be physical objects and not photons, waves, or interference patterns created by any or all the above. Disclaimer: This is neither a new nor a unique concept. 73, ac6xg |
"Waves of Average Power"
Jim Kelley wrote:
Cecil Moore wrote: Jim Kelley wrote: I don't think it matters where it is, or how much space is involved. For a single source to create an interferernce pattern, there must be a reflector somewhere. An antenna tuner for example. Interference is the result of the overlap of waves. Do you consider a dipole in free space to be a "single source"? There is no reflector yet there is plenty of interference. If there is no reflector and no splitter to redirect a portion of the ratiated energy, but an interference pattern still results, then there must be more than a single source. It should be fairly obvious that both parts of the antenna must be present in order to generate the dipole-type interference pattern. 73, ac6xg A dipole is by no means a single (point) source. Each tiny part of the dipole creates a field proportional to the current at that tiny part, so in effect it behaves like an infinite number of sources which are spread out in space along the dipole conductors. Interference of all those various fields is what creates the familiar dipole radiation pattern. In fact, moment method antenna analysis programs such as NEC and EZNEC break the antenna into a finite number of segments and calculate the current (magnitude and phase) on each segment. It then calculates the field produced by each segment according to its length, orientation, and current. The sum of the fields is shown as the radiation pattern. This process can be done manually as well. The hypothetical isotropic radiator is a point source. It has a perfectly spherical pattern because there's no interference. Roy Lewallen, W7EL |
"Waves of Average Power"
Cecil Moore wrote: Jim Kelley wrote: Do you consider a dipole in free space to be a "single source"? There is no reflector yet there is plenty of interference. If there is no reflector and no splitter to redirect a portion of the ratiated energy, but an interference pattern still results, then there must be more than a single source. It should be fairly obvious that both parts of the antenna must be present in order to generate the dipole-type interference pattern. Just trying to understand - are you considering the two sections of dipole to be two separate sources? I think I know what you want me to say, but I need you to go first. How many sources is a monopole? :-) jk |
"Waves of Average Power"
Cecil Moore wrote:
K7ITM wrote: Of course, it does not require coherent sources to see the effects of interference. True, but it does require coherent waves to accomplish the permanent wave cancellation described at: micro.magnet.fsu.edu/primer/java/scienceopticsu/interference/waveinteractions/index.html "... when two waves of equal amplitude and wavelength that are 180-degrees ... out of phase with each other meet, they are not actually annihilated, ... All of the photon energy present in these waves must somehow be recovered or redistributed in a new direction, according to the law of energy conservation ... Instead, upon meeting, the photons are redistributed to regions that permit constructive interference, so the effect should be considered as a redistribution of light waves and photon energy rather than the spontaneous construction or destruction of light." This is what happens to the reflected waves at a Z0-match in a transmission line. Cecil, The FSU website you like to reference is a perfect example of the problem Jim is describing. As shown, the FSU demonstration is physically impossible. There is no way for two plane waves to be trucking along independently and then suddenly decide to interfere. There is basically nothing wrong with the demo as far as it goes; it nicely shows the effects of combined phase and amplitude on the resulting wave. However, the demo is not rigorous science or mathematics. It is not suitable as an authoritative reference. 73, Gene W4SZ |
"Waves of Average Power"
Jim Kelley wrote:
I think I know what you want me to say, but I need you to go first. How many sources is a monopole? :-) As many segments as are specified using EZNEC. Does that help? -- 73, Cecil http://www.w5dxp.com |
"Waves of Average Power"
Gene Fuller wrote:
As shown, the FSU demonstration is physically impossible. There is no way for two plane waves to be trucking along independently and then suddenly decide to interfere. They do NOT "truck along and then suddenly decide to interfere". Such nonsense is just a strawman presented for the purpose of obfuscating the technical facts. The two independent waves are generated at a physical impedance discontinuity, the Z0-match point, and are immediately canceled at that point. The energy in the canceled waves is redistributed in the only other direction possible in a one-dimensional transmission line. Exactly the same thing happens when the external reflection is canceled by the internal reflection at a non-reflective 1/4WL thin-film coating on glass. Quoting the Melles Groit web page: "In the absence of absorption or scatter, the principle of conservation of energy indicates all 'lost' reflected intensity will appear as enhanced intensity in the transmitted beam." i.e. the energy re-reflected at the Z0-match joins the forward wave toward the load. The conservation of energy principle will not allow any other result. Dr. Best's phantom waves continuing to flow toward the source with zero energy is just a wet dream. -- 73, Cecil http://www.w5dxp.com |
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