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#1
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I'm preparing an article for a local radio club magazine about the nature of
radio and electromagnetic radiation in general. While this is a non mathematical and general descriptive treatment of the subject it is a challenge to make it clear and consistent. I know this group has some expertise on this subject and would appreciate any constructive comment and suggestions regarding the attached article. http://members.optushome.com.au/vk6ysf/vk6ysf/radio.htm Thank you for your time. Regards Peter VK6YSF |
#2
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On Apr 30, 4:14*am, "Peter" wrote:
I know this group has some expertise on this subject and would appreciate any constructive comment and suggestions regarding the attached article. The two-dimensional Fig. 2-2 graph is confusing in that it could be inferred that the E and H fields are 90 degrees out of phase in time and are never zero at the same time. The E and H fields are in phase in time as demonstrated by Fig. 2-4. -- 73, Cecil, w5dxp.com |
#3
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On Fri, 30 Apr 2010 05:12:38 -0700 (PDT), Cecil Moore
wrote: On Apr 30, 4:14*am, "Peter" wrote: I know this group has some expertise on this subject and would appreciate any constructive comment and suggestions regarding the attached article. The two-dimensional Fig. 2-2 graph is confusing in that it could be inferred that the E and H fields are 90 degrees out of phase in time and are never zero at the same time. The E and H fields are in phase in time as demonstrated by Fig. 2-4. Hmmm. I'm no expert, but I thought they were 90 degrees out of phase. It's the rapidly changing H field that creates the E field and vica versa. If you look closely, Fig 2-4 also shows them 90 degrees out of phase. To the OP, heat is not electromagnetic radiation. Light and x-rays are. You can heat something by pointing em radiation at it and something that is hot gives off infra-red em radiation, but heat itself is not em radiation. Pat |
#4
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On Apr 30, 9:00*am, wrote:
On Fri, 30 Apr 2010 05:12:38 -0700 (PDT), Cecil Moore wrote: On Apr 30, 4:14*am, "Peter" wrote: I know this group has some expertise on this subject and would appreciate any constructive comment and suggestions regarding the attached article. The two-dimensional Fig. 2-2 graph is confusing in that it could be inferred that the E and H fields are 90 degrees out of phase in time and are never zero at the same time. The E and H fields are in phase in time as demonstrated by Fig. 2-4. Hmmm. *I'm no expert, but I thought they were 90 degrees out of phase. It's the rapidly changing H field that creates the E field and vica versa. *If you look closely, Fig 2-4 also shows them 90 degrees out of phase. To the OP, heat is not electromagnetic radiation. *Light and x-rays are. *You can heat something by pointing em radiation at it and something that is hot gives off infra-red em radiation, but heat itself is not em radiation. * Pat It is accepted that radiation is "an acceleration that generates or transfers a charge ". This is an empty statement if one cannot explain the mechanics of the operation.Certainly you have to determine what you have in hand to provide this action, and at the present time there is no agreement whether it is a wave flow of a constituent, what ever that may be, or a particle. Therefore one has to determine exactly what we are going to accelerate and how we are going to avoid the effects of gravity since radiation does not follow the action of a descending lob. This as yet has not been determined, so we cannot begin to understand! For me I see a wave as being an adjective and a particle as a noun. But a word of warning,physicists do not follow the same rules of the general public, so if you have a day or two to spare get a physicist to explain exactly what a 'wave' is and how does it fit with the required straight line accelerating trajectory that opposes gravity! You just cannot explain "radio" until you determine what you are accelerating and how. Sorry about that Regards Art |
#5
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![]() It is accepted that radiation is "an acceleration that generates or transfers a charge ". This is an empty statement if one cannot explain the mechanics of the operation.Certainly you have to determine what you have in hand to provide this action, and at the present time there is no agreement whether it is a wave flow of a constituent, what ever that may be, or a particle. Therefore one has to determine exactly what we are going to accelerate and how we are going to avoid the effects of gravity since radiation does not follow the action of a descending lob. This as yet has not been determined, so we cannot begin to understand! For me I see a wave as being an adjective and a particle as a noun. But a word of warning,physicists do not follow the same rules of the general public, so if you have a day or two to spare get a physicist to explain exactly what a 'wave' is and how does it fit with the required straight line accelerating trajectory that opposes gravity! You just cannot explain "radio" until you determine what you are accelerating and how. Sorry about that Regards Art You are really good, Art. How do you keep it up? You make new and fresh nonsense up with very many of your posts. Not every one, but you do have to carry on your themes after all. Still, it's quite an effort you put into it. How do you continue to make almost no sense? That's really tough. I mean, even random chance would say you occasionally have to be realistic. tom K0TAR |
#6
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On Apr 30, 9:22*pm, tom wrote:
It is accepted that radiation is "an acceleration that generates or transfers a charge ". This is an empty statement if one cannot explain the mechanics of the operation.Certainly you have to determine what you have in hand to provide this action, and at the present time there is no agreement whether it is a wave flow of a constituent, what ever that may be, or a particle. Therefore one has to determine exactly what we are going to accelerate and how we are going to avoid the effects of gravity since radiation does not follow the action of a descending lob. * * *This as yet has not been determined, so we cannot begin to understand! For me I see a wave as being an adjective and a particle as a noun. But a word of warning,physicists do not follow the same rules of the general public, so if you have a day or two to spare get a physicist to explain exactly what a 'wave' is and how does it fit with the required straight line accelerating trajectory that opposes gravity! You just cannot explain "radio" until you determine what you are accelerating and how. Sorry about that Regards Art You are really good, Art. *How do you keep it up? You make new and fresh nonsense up with very many of your posts. *Not every one, but you do have to carry on your themes after all. Still, it's quite an effort you put into it. *How do you continue to make almost no sense? *That's really tough. *I mean, even random chance would say you occasionally have to be realistic. tom K0TAR As an engineer can't afford to act on theories alone only those that have already be established. In other words I can act on a full picture made of jigsaw parts but not a partial picture. Therefore one must deal with fully melded and interacting parts that are consistant to reality. Thus I adhere to classical physics and factual observances or laws without straying from the path I have chosen from interconnecting parts. Quantum theory is based on probabilities and associated math. Any body who has been to the race track knows that this form of thinking has its fallacies thus probabilities has moved towards string theory. I stick to classical physics as they have a history of success with the laws that they have established but unfortunately physicists have corrupted the language of observances. For instance we had a discussion on Leptons, colour etc. Physicists recognise that colour as the rest of the world knows it as a means of separation of its observed actions instead of labelling it lepton1 or lepton 2.Same goes for hadrons, they actually could be a single type particle but physicists label them by the action that they exhibit on observance. Why do you think that the idea of a mad scientist hangs on to this day. They did similar things with respect to waves which in their world has nothing to do with water, tides e.t.c. So for me there is merit in sticking to points raised by classical physics since they are tried and true under examination and have not exploded by categerizing particles by a particular observation. After all, both a dog and a cat have a tail they can wag but the real world can have the same observation of different entitiesand vica versa. What I desire the most is for somebody to challenge my statements based on documented observations and laws bearing in mind that the written word comes after factual examination and not before.As yet nobody has pointed out a fallacy that is in conflict with presently known laws, and I mean nobody. If there is a conflict then I will discard all. But remember, I do not make computer programs on radiators but they all confirm the presence of particles and equilibrium and I have had no way of manipulating that to conform to my thinking. They show that maximum radiation is obtained when material resistance drops to zero and radiation rises to a maximum via current flow outside the member to elevate particles at rest on the surface. I couldn't possibly string some thing like that as a joke or by not taking my medicine. |
#7
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#8
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Roy Lewallen wrote in
: The time phase angle between E and H is determined by the medium the wave is propagating through. The (complex) ratio of E to H is called the intrinsic impedance of the medium, and for lossless media, it's always a purely real number (about 377 ohms for air or free space), meaning that E and H are in phase. Only when propagating through a lossy medium are E and H not in time phase, and then the maximum phase difference is always less than 45 degrees. If I understand this correctly, a field arrangement with E and H in time and space quadrature is not propagating energy, but rather energy exchange. In very close to an antenna, the time phase relationship of E and H may be close to quadrature due to the inductive or reactive field close to the conductors, but that changes eventually to 'in-phase' in the far radiation field in free space (as the induction field components decay more quickly with distance than the radiation field components). If that is the case, the complex value of E/H varies from very close to the far field. I have seen plots of E/H vs distance that treated E/H as a real number, but I suspect that it is more complex when all of the components of E and H are included. Thoughts? Owen |
#9
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On Apr 30, 5:05*pm, Owen Duffy wrote:
Roy Lewallen wrote om: The time phase angle between E and H is determined by the medium the wave is propagating through. The (complex) ratio of E to H is called the intrinsic impedance of the medium, and for lossless media, it's always a purely real number (about 377 ohms for air or free space), meaning that E and H are in phase. Only when propagating through a lossy medium are E and H not in time phase, and then the maximum phase difference is always less than 45 degrees. If I understand this correctly, a field arrangement with E and H in time and space quadrature is not propagating energy, but rather energy exchange. In very close to an antenna, the time phase relationship of E and H may be close to quadrature due to the inductive or reactive field close to the conductors, but that changes eventually to 'in-phase' in the far radiation field in free space (as the induction field components decay more quickly with distance than the radiation field components). If that is the case, the complex value of E/H varies from very close to the far field. I have seen plots of E/H vs distance that treated E/H as a real number, but I suspect that it is more complex when all of the components of E and H are included. Thoughts? Owen Owen By observation the E and H fields can be seen as a tank circuit where all vectors are accounted for so that one follows the notion that energy cannot be created or destroyed plus the other laws of Newton. When we stray from that scenario we get into new theories or imaginations The moment we stray from boundary laws one is coersed into thinking like somebody of a lesser nature than past masters who determine phenomina from observation that is matched by known principles. How on earth can we relate to near fields and far fields if we haven't decided what the media concists of. My approach was to stick with the laws of Maxwell which dictates static and dynamic fields where all forces are accounted for, which shows that gravity can only be negated by the use of Newton's laws. Thus my foundations were not built on a layer of sand but what is accepted via Maxwell's laws. In other words, the laws of Maxwell points to the presence of particles when dealing with fields and displacements by virtue of the units used. There are lots of things that exhibit properties of other materials and thus by observation can be compared to other things in action, but they should never be considered as one and the same unless they are matched in their entirety. Particles and waves have lurched beyond science by considering them to be one and the same purely by action and not by substance. If one is going to discuss energy exchange as with inductance and capacitance to determine relative phase angles , fields etc one cannot stray from the tank circuit observations. Regards Art |
#10
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Owen Duffy wrote:
Roy Lewallen wrote in : The time phase angle between E and H is determined by the medium the wave is propagating through. The (complex) ratio of E to H is called the intrinsic impedance of the medium, and for lossless media, it's always a purely real number (about 377 ohms for air or free space), meaning that E and H are in phase. Only when propagating through a lossy medium are E and H not in time phase, and then the maximum phase difference is always less than 45 degrees. If I understand this correctly, a field arrangement with E and H in time and space quadrature is not propagating energy, but rather energy exchange. I believe that's correct, but there's no medium in which that would take place -- with a plane wave at least. In very close to an antenna, the time phase relationship of E and H may be close to quadrature due to the inductive or reactive field close to the conductors, but that changes eventually to 'in-phase' in the far radiation field in free space (as the induction field components decay more quickly with distance than the radiation field components). If that is the case, the complex value of E/H varies from very close to the far field. I have seen plots of E/H vs distance that treated E/H as a real number, but I suspect that it is more complex when all of the components of E and H are included. Thoughts? Yes, E/H varies a great deal in both magnitude and phase in the near field. The intrinsic Z describes only the E/H ratio of a plane wave propagating in the far field. This can be easily investigated with NEC, EZNEC, or any modeling program that provides near field results. Incidentally, the physical orientation of E and H, and I believe their time phase, can be quite different when bounded by conductors as in a waveguide. Roy Lewallen, W7EL |
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