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John KD5YI wrote:
"Cecil Moore" wrote in message ... John KD5YI wrote: I think any inductor with the same inductance, Q, and self-resonant frequency will give the same velocity factor and delay as your Bugcatcher. That may or may not be true - I don't have an opinion one way or another - and it is NOT part of my argument. My argument deals only with 75m Texas Bugcatcher coils and other large air- core loading coils used on 75m. If it IS true, then the point I tried to make that you are making a distributed component from a lumped one is valid. That's what caused me to object to your earlier post. And, by the way, I feel the same way you do except about people who are afraid to consider lumped components. Perhaps they do not have what it takes to judge when a proper substitution can be made. John Anyone can take a small inductor, such as Roy described, and try to analyze all the currents and such in it using a distributed model at low or moderate frequencies. If they do, though, they'll just come up with what they'd have come up with treating their small inductor as a lumped element. Cecil has distributed elements on the brain. It's what comes of falling in love with your own theories. 73, Tom Donaly, KA6RUH |
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Jim Kelley wrote:
Presumably there is a lower limit to the number of turns the coil would have to have, or an upper limit to the pitch angle, in order to behave as described - a helical sheath. Tesla coils usually have at least a few hundred turns wound closely together, and often operate at wavelengths considerably longer that 75 meters. One could easily argue that 30 turns do not a Tesla coil make, in which case Eq. 32 would not apply. Dr. Corum says that it behaves as a helical sheath when it is electrically longer than 15 degrees (0.04WL). The frequency doesn't matter - just the electrical length. Of course, it takes more turns at a lower frequency since the reactance is proportional to frequency. Eq. 32 is not concerned with the number of turns, just that the coil is electrically longer than 15 degrees and is therefore outside the range for which the lumped-circuit model is valid. Note that the title of the paper is: "RF Coils, Helical Resonators and Voltage Magnification by Coherent Spatial Modes". "Tesla coil" does not even appear in the title. A Tesla coil can be 1/4WL self-resonant all by itself. Thus, 30 turns could easily be a Tesla coil over a certain range of HF frequencies. Some Tesla coils have a top hat and are operated below their 1/4WL self-resonant frequency. In Dr. Corum's paper, take a look at "Figure 2, A capacitively tuned distributed resonator" and tell us how it differs from a 75m mobile antenna with a top hat. The 1/4WL self-resonant frequency for a 75m Texas Bugcatcher coil has been measured at ~6.5 MHz where it is known to be electrically 90 degrees long. Why does anyone have a problem with it being electrically 40 degrees long on 4 MHz? In "Fields and Waves ...", by Ramo and Whinnery, the analysis of a helical sheath assumes an infinitely long helical sheath for the purpose of eliminating reflections. Does that ring a bell? Hint: The current on a standing-wave antenna cannot be used to measure phase shift or delay. Yet, that is exactly what w8ji and w7el tried to do. I once turned my 75m mobile Texas Bugcatcher system into a Tesla coil. I had a latch to which I could connect the top ball of the antenna when I needed to lean it over for more clearence. I was at a hamfest at night and had forgotten I had the antenna latched down. I started transmitting and my friend told me I was drawing a two-inch arc from the tip of my antenna to the pickup body. It was indeed "Voltage Magnification by Coherent Spatial Modes". http://www.ttr.com/TELSIKS2001-MASTER-1.pdf -- 73, Cecil, IEEE, OOTC, http://www.w5dxp.com |
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John KD5YI wrote:
If it IS true, then the point I tried to make that you are making a distributed component from a lumped one is valid. That's what caused me to object to your earlier post. There are coils for which the lumped-circuit model is valid. There are coils for which the lumped-circuit model is not valid. I am only interested in discussing coils for which the lumped-circuit model is invalid, i.e. coils that are electrically longer than 15 degrees, e.g. a large air-core 75m Texas Bugcatcher coil which measures about 40 degrees on 4 MHz. I honestly don't know if the lumped-circuit model works for 70 uH toroidal coils. I do know it doesn't work for a 75m Texas Bugcatcher coil. The people who insist on analyzing tiny toroidal coils instead of 75m Texas Bugcatcher coils are afraid of the technical truth and it's easy to see why. -- 73, Cecil, IEEE, OOTC, http://www.w5dxp.com |
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Art Unwin wrote:
Does your photon come in different sizes, color and potential energy? It comes in different wavelengths. It certainly comes in any and all colors and frequencies outside the range of "color". All of its energy is the result of its speed of light velocity. It has zero rest mass. It has the equivalent of mass when traveling at the speed of light. m=e/c^2 -- 73, Cecil, IEEE, OOTC, http://www.w5dxp.com |
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Tom Donaly wrote:
Meaning you don't want anyone to disagree with you. What I invite is someone disagreeing with me about a 75m Texas Bugcatcher coil along with some technical proof that I am wrong. All I have gotten so far is ad hominem attacks. Where's the beef? Dr. Corum's empirically-based equations do not work for toroidal inductors so they are outside the scope of my discussion. Why not discuss the most common large air-core coils used for loading 75m mobile antennas? No he wouldn't. You don't know what he would have measured. I have exactly the same coil that Tom used for his "measurements". I have measured the traveling wave delay through the coil by loading it with a 5k resistor to eliminate reflections. I do know what he would measure if he would only run the experiment correctly. You could do it too if you so chose. x and y are the current sample points. source---x-Tom's coil-y--5k load +-------------------------+ Maxwell's equations don't say anything about "slow-wave structures." If you are saying that Maxwell's equations are invalid for slow-wave structures, your argument is with Ramo, Whinnery, and Dr. Corum, not with me. http://www.w8ji.com/agreeing_measurements.htm "As described in my posting on rraa of November 11, the inductor 'replaces' about 33 electrical degrees of the antenna." Are you sure that isn't a quote from Reg Edwards, whose ideas you stole in the first place? You are free to access the above web page to see who wrote it. If Dr. Corum stole Reg's ideas, he should have given him the credit. Dr. Corum does provide 50 references for his paper but Reg is not one of them. However, here is a partial list: 7. J. D. Kraus, "Antennas" 19. F. E. Terman, "Resonant Lines in Radio Circuits" 23. J. D. Ryder, "Networks, Lines, and Fields" 29. S. Ramo and J. R. Whinnery, "Fields and Waves in Modern Radio" 30. R. W. P. King, "Electromagnetic Engineering" 43. M. Born and E. Wolf, "Principles of Optics" -- 73, Cecil, IEEE, OOTC, http://www.w5dxp.com |
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Tom Donaly wrote:
Anyone can take a small inductor, such as Roy described, and try to analyze all the currents and such in it using a distributed model at low or moderate frequencies. If they do, though, they'll just come up with what they'd have come up with treating their small inductor as a lumped element. One wonders why some people insist on a "small toroidal inductor" which obviously agrees with the lumped-circuit model instead of analyzing a 75m Texas Bugcatcher loading coil which just as obviously violates the presuppositions of the lumped-circuit model. Instead of the "small toroidal inductor", let's discuss w8ji's 100 turn, 2" diameter, 10 inch long air-core coil through which he measured that ridiculous 3 nS delay after which w7el posted some "agreeing measurements" while asserting that the electrical length of the coil was 33 degrees. Does anyone else realize that 33 degrees in 3 nS at 4 MHz is faster than light speed? Are you guys so afraid of losing face that you are willing to post technical falsehoods? -- 73, Cecil, IEEE, OOTC, http://www.w5dxp.com |
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Cecil Moore wrote:
Tom Donaly wrote: Meaning you don't want anyone to disagree with you. What I invite is someone disagreeing with me about a 75m Texas Bugcatcher coil along with some technical proof that I am wrong. All I have gotten so far is ad hominem attacks. Where's the beef? Dr. Corum's empirically-based equations do not work for toroidal inductors so they are outside the scope of my discussion. Why not discuss the most common large air-core coils used for loading 75m mobile antennas? No he wouldn't. You don't know what he would have measured. I have exactly the same coil that Tom used for his "measurements". I have measured the traveling wave delay through the coil by loading it with a 5k resistor to eliminate reflections. I do know what he would measure if he would only run the experiment correctly. You could do it too if you so chose. x and y are the current sample points. source---x-Tom's coil-y--5k load +-------------------------+ Maxwell's equations don't say anything about "slow-wave structures." If you are saying that Maxwell's equations are invalid for slow-wave structures, your argument is with Ramo, Whinnery, and Dr. Corum, not with me. http://www.w8ji.com/agreeing_measurements.htm "As described in my posting on rraa of November 11, the inductor 'replaces' about 33 electrical degrees of the antenna." Are you sure that isn't a quote from Reg Edwards, whose ideas you stole in the first place? You are free to access the above web page to see who wrote it. If Dr. Corum stole Reg's ideas, he should have given him the credit. Dr. Corum does provide 50 references for his paper but Reg is not one of them. However, here is a partial list: 7. J. D. Kraus, "Antennas" 19. F. E. Terman, "Resonant Lines in Radio Circuits" 23. J. D. Ryder, "Networks, Lines, and Fields" 29. S. Ramo and J. R. Whinnery, "Fields and Waves in Modern Radio" 30. R. W. P. King, "Electromagnetic Engineering" 43. M. Born and E. Wolf, "Principles of Optics" I didn't write that the Corums stole Reg's ideas, I wrote that you did. You know that. Quit trying to hide behind authority. Do you really think that the people who wrote the references you cite, if they were all alive today, would agree with you? Ha, ha, ha. Nice try, Cecil. 73, Tom Donaly, KA6RUH |
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Cecil Moore wrote:
Jim Kelley wrote: Presumably there is a lower limit to the number of turns the coil would have to have, or an upper limit to the pitch angle, in order to behave as described - a helical sheath. Tesla coils usually have at least a few hundred turns wound closely together, and often operate at wavelengths considerably longer that 75 meters. One could easily argue that 30 turns do not a Tesla coil make, in which case Eq. 32 would not apply. Dr. Corum says that it behaves as a helical sheath when it is electrically longer than 15 degrees (0.04WL). The frequency doesn't matter - just the electrical length. :-) And obviously it's electrical length depends on Vp, which depends on whether it behaves as a helical sheath. Note that the title of the paper is: "RF Coils, Helical Resonators and Voltage Magnification by Coherent Spatial Modes". "Tesla coil" does not even appear in the title. Are you trying to imply that the paper isn't about Tesla coils? In Dr. Corum's paper, take a look at "Figure 2, A capacitively tuned distributed resonator" and tell us how it differs from a 75m mobile antenna with a top hat. Hopefully you're not serious. Because, borrowing from Richard Clark, it's a 'cartoon'. The 1/4WL self-resonant frequency for a 75m Texas Bugcatcher coil has been measured at ~6.5 MHz where it is known to be electrically 90 degrees long. Why does anyone have a problem with it being electrically 40 degrees long on 4 MHz? Maybe it is. I happen to think that because of its simplicity, it's an attractive notion. But it's not clear to me that the article applies to coils with these parameters, and I haven't seen any (reputable) empirical evidence to support it. In "Fields and Waves ...", by Ramo and Whinnery, the analysis of a helical sheath assumes an infinitely long helical sheath for the purpose of eliminating reflections. Does that ring a bell? Hint: The current on a standing-wave antenna cannot be used to measure phase shift or delay. Yet, that is exactly what w8ji and w7el tried to do. What do you suppose Corum^2 meant when they wrote "Experimentally, the wave velocity and velocity factor may be measured by determining the axial length of the standing wave pattern on the helical structure"? I once turned my 75m mobile Texas Bugcatcher system into a Tesla coil. I had a latch to which I could connect the top ball of the antenna when I needed to lean it over for more clearence. I was at a hamfest at night and had forgotten I had the antenna latched down. I started transmitting and my friend told me I was drawing a two-inch arc from the tip of my antenna to the pickup body. It was indeed "Voltage Magnification by Coherent Spatial Modes". No offense, but some of their work seems aimed squarely at the 'Art Bell' crowd. Describing constructive interference as "voltage magnification" is an example. It's as if they were publishing in the 19th century. ac6xg |
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Tom Donaly wrote:
I didn't write that the Corums stole Reg's ideas, I wrote that you did. But I am only quoting Drs. Corum, not Reg. If anyone stole Reg's ideas, it was Dr. Corum, not I. Do you really think that the people who wrote the references you cite, if they were all alive today, would agree with you? As a matter of fact, Dr. Balanis did agree with me when I took his antenna class at ASU in the early 90's. There were some Motorola people in the class who asked, "Why do Intel people know so much about antennas?" Dr. Balanis and I worked closely together on a joint ASU/Intel project. The complete absence of technical rebuttal in your posting is noted. I don't know much about you, Tom, but you seem to be more ad hominem than technical. -- 73, Cecil, IEEE, OOTC, http://www.w5dxp.com |
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On May 7, 7:51*am, Cecil Moore wrote:
Tom Donaly wrote: Meaning you don't want anyone to disagree with you. What I invite is someone disagreeing with me about a 75m Texas Bugcatcher coil along with some technical proof that I am wrong. All I have gotten so far is ad hominem attacks. Where's the beef? Dr. Corum's empirically-based equations do not work for toroidal inductors so they are outside the scope of my discussion. Why not discuss the most common large air-core coils used for loading 75m mobile antennas? No he wouldn't. You don't know what he would have measured. I have exactly the same coil that Tom used for his "measurements". I have measured the traveling wave delay through the coil by loading it with a 5k resistor to eliminate reflections. I do know what he would measure if he would only run the experiment correctly. You could do it too if you so chose. x and y are the current sample points. source---x-Tom's coil-y--5k load * *+-------------------------+ Maxwell's equations don't say anything about "slow-wave structures." If you are saying that Maxwell's equations are invalid for slow-wave structures, your argument is with Ramo, Whinnery, and Dr. Corum, not with me. http://www.w8ji.com/agreeing_measurements.htm "As described in my posting on rraa of November 11, the inductor 'replaces' about 33 electrical degrees of the antenna." Are you sure that isn't a quote from Reg Edwards, whose ideas you stole in the first place? You are free to access the above web page to see who wrote it. If Dr. Corum stole Reg's ideas, he should have given him the credit. Dr. Corum does provide 50 references for his paper but Reg is not one of them. However, here is a partial list: 7. J. D. Kraus, "Antennas" 19. F. E. Terman, "Resonant Lines in Radio Circuits" 23. J. D. Ryder, "Networks, Lines, and Fields" 29. S. Ramo and J. R. Whinnery, "Fields and Waves in Modern Radio" 30. R. W. P. King, "Electromagnetic Engineering" 43. M. Born and E. Wolf, "Principles of Optics" -- 73, Cecil, IEEE, OOTC, *http://www.w5dxp.com I agree whole heartedly. Maxwell never included slow waves which is a result of lumped loads. Maxwell equations studies have been rigorous with respect to accounting for all forces involved in radiation for maximum efficiency. It stands to reason then that for efficiency a load is not valid. Thus Reg was correct in seeing a transmission line as an antenna with just distributed loads when the length is in terms of a WL i.e. in equilibrium. Thus Kraus's antennas are not in equilibrium and thus deviated away from Maxwell's laws. Same goes for Corum ! And Ramo still talks of waves so he is in the same bracket. All electrical engineering turns topsey turvey when engineers are forced to consider particles instead of waves and I will be the leader of that change that will stop CERN in its tracks Art |
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Cecil Moore wrote:
Tom Donaly wrote: I didn't write that the Corums stole Reg's ideas, I wrote that you did. But I am only quoting Drs. Corum, not Reg. If anyone stole Reg's ideas, it was Dr. Corum, not I. Do you really think that the people who wrote the references you cite, if they were all alive today, would agree with you? As a matter of fact, Dr. Balanis did agree with me when I took his antenna class at ASU in the early 90's. There were some Motorola people in the class who asked, "Why do Intel people know so much about antennas?" Dr. Balanis and I worked closely together on a joint ASU/Intel project. In the early '90's you hadn't come up with your ideas yet. How could Balanis agree with you before the fact? Again, nice try. The complete absence of technical rebuttal in your posting is noted. I don't know much about you, Tom, but you seem to be more ad hominem than technical. You're being ad hominem by accusing me of being ad hominem. Come up with some evidence that makes sense concerning your ideas and we can talk. 73, Tom Donaly, KA6RUH |
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Jim Kelley wrote:
Cecil Moore wrote: :-) And obviously it's electrical length depends on Vp, which depends on whether it behaves as a helical sheath. There is a test equation in the Drs. Corum paper that indicates whether a particular coil meets the requirements for a helical sheath or not. A 75m Texas Bugcatcher coil meets the requirements. A small toroidal coil does not. If you had ever actually read the article, you would know that. Are you trying to imply that the paper isn't about Tesla coils? No, I am asserting that the paper isn't *only* about Tesla coils. It is about RF coils in general. Hint: "RF Coils" are the first two words in the title. it's a 'cartoon'. Actually, it's a graphic diagram of a Tesla coil with a top hat or a 75m Texas Bugcatcher with a top hat. There is no conceptual difference in the diagrams. The only difference is that we hams avoid arcing by running reduced power compared to Tesla coils. But it's not clear to me that the article applies to coils with these parameters, and I haven't seen any (reputable) empirical evidence to support it. Then I would suggest that you read the article. There is a test for validity on page 4. Let's see if you can use your "expertise" to locate it. Actually, I will make it easy for you. Here is an EXCEL file that I generated based on the Corum paper which includes the test for validity in red. http://www.w5dxp.com/CoilZ0VF.xls What do you suppose Corum^2 meant when they wrote "Experimentally, the wave velocity and velocity factor may be measured by determining the axial length of the standing wave pattern on the helical structure"? EZNEC can do that for us since EZNEC will display the current in each segment. I have been explaining that for five+ years. Have you not looked at any of the EZNEC results I have posted or have you just not been able to comprehend them? It can also be done, as it was for Tesla coils, by measuring the electric field along the coil. Describing constructive interference as "voltage magnification" is an example. Well, don't blame me. Drs. Corum think they are the same thing, just using different words. I understand what they mean. Obviously, the highest "voltage magnification" occurs at the point where the forward and reflected voltages are in phase, i.e. constructive interference. If you disagree, let's hear your theory on the subject. Jim, you seem to object to anyone, including Drs. Corum, choosing slightly different words from the ones you would choose. Are you actually omniscient? -- 73, Cecil, IEEE, OOTC, http://www.w5dxp.com |
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Tom Donaly wrote:
In the early '90's you hadn't come up with your ideas yet. How could Balanis agree with you before the fact? Again, nice try. On the contrary, in the early 90's I had not published my ideas yet. Dr. Balanis helped me to develop the very ideas that I have published and he agreed with them. Come up with some evidence that makes sense concerning your ideas and we can talk. I have presented my evidence long ago and you have ignored it in favor of ad hominem attacks. I cannot recall a single technical argument from you. For all I know, you are an 8 year old brat with access to his mother's computer. I would like nothing better than to engage in a real technical argument with you. You can start by producing technical arguments against the information on my web page. If you have EZNEC, you can verify everything I say by downloading the EZNEC files at: http://www.w5dxp.com/current2.htm -- 73, Cecil, IEEE, OOTC, http://www.w5dxp.com |
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On May 7, 12:43*pm, Cecil Moore wrote:
Jim Kelley wrote: Cecil Moore wrote: :-) And obviously it's electrical length depends on Vp, which depends on whether it behaves as a helical sheath. There is a test equation in the Drs. Corum paper that indicates whether a particular coil meets the requirements for a helical sheath or not. A 75m Texas Bugcatcher coil meets the requirements. A small toroidal coil does not. If you had ever actually read the article, you would know that. Are you trying to imply that the paper isn't about Tesla coils? No, I am asserting that the paper isn't *only* about Tesla coils. It is about RF coils in general. Hint: "RF Coils" are the first two words in the title. it's a 'cartoon'. Actually, it's a graphic diagram of a Tesla coil with a top hat or a 75m Texas Bugcatcher with a top hat. There is no conceptual difference in the diagrams. The only difference is that we hams avoid arcing by running reduced power compared to Tesla coils. But it's not clear to me that the article applies to coils with these parameters, and I haven't seen any (reputable) empirical evidence to support it. Then I would suggest that you read the article. There is a test for validity on page 4. Let's see if you can use your "expertise" to locate it. Actually, I will make it easy for you. Here is an EXCEL file that I generated based on the Corum paper which includes the test for validity in red. http://www.w5dxp.com/CoilZ0VF.xls What do you suppose Corum^2 meant when they wrote "Experimentally, the wave velocity and velocity factor may be measured by determining the axial length of the standing wave pattern on the helical structure"? EZNEC can do that for us since EZNEC will display the current in each segment. I have been explaining that for five+ years. Have you not looked at any of the EZNEC results I have posted or have you just not been able to comprehend them? It can also be done, as it was for Tesla coils, by measuring the electric field along the coil. Describing constructive interference as "voltage magnification" is an example. Well, don't blame me. Drs. Corum think they are the same thing, just using different words. I understand what they mean. Obviously, the highest "voltage magnification" occurs at the point where the forward and reflected voltages are in phase, i.e. constructive interference. If you disagree, let's hear your theory on the subject. Jim, you seem to object to anyone, including Drs. Corum, choosing slightly different words from the ones you would choose. Are you actually omniscient? -- 73, Cecil, IEEE, OOTC, *http://www.w5dxp.com But Cecil the Bugcatcher does not conform with Maxwell's laws and EZNEC has no provision to explain to you when you deviate from Maxwell's laws with invalid designs All Eznec does is to apply the best math available via approximations to what you direct it to do. It is not able to inform you or change the input so it does conform to Maxwell's equations. A typical description of garbage in garbage out with respect to a rigourous examination for accuracy. So to refer to Eznec as an authority of accuracy is the same as an author who details all that agree with him at the outset. This is not to say that EZNEC is not a useful tool or not close in it's approximations. It is a tool that matches the requirements of the average ham and the education given him. Art |
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Cecil Moore wrote:
Are you actually omniscient? I know bullcrap when I see it. ac6xg |
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Art Unwin wrote:
But Cecil the Bugcatcher does not conform with Maxwell's laws In what way does a Bugcatcher not conform with Maxwell's equations? In "Fields and Waves ...", Ramo and Whinnery give the actual Maxwell equations for a loading coil. -- 73, Cecil, IEEE, OOTC, http://www.w5dxp.com |
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Art Unwin wrote:
I don't know about waves but my understanding is that all colors come from the mixing of the three basic colors, or is it four? When you mix frequencies I would imagine you could arrive at all possible frequencies. I think you should drop the idea of waves with respect to frequency. If you observe a rainbow how many basic colors are there in the mix! The visible spectrum does not include "basic colors" It pretty much has all of them. Well, not Magenta. Is magenta a color? And when you talk "basic, are you talking Cyan, Magenta, Yellow, or Red, Green, Blue. It makes a difference. In a projector isn't there just three filters required for a movie in color? One thing you have to get into your mind is the idea of basic temperature and mass without energy. That would be a black body radiator at absolute 0. |
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Jim Kelley wrote:
Cecil Moore wrote: Are you actually omniscient? I know bullcrap when I see it. So you have the omniscient gift of recognizing bullcrap just by observing it with absolutely no technical rebuttal and no possibility of your being conceptually wrong? Exactly what is it about Drs. Corum paper that you don't understand? Jim, if you want to retain one iota of respect, please present a technical argument to refute what I have asserted. Your gut feelings of "bullcrap" are completely irrelevant. How about your equations that prove Dr. Corums's IEEE paper's equations are wrong? -- 73, Cecil, IEEE, OOTC, http://www.w5dxp.com |
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Michael Coslo wrote:
Art Unwin wrote: I don't know about waves but my understanding is that all colors come from the mixing of the three basic colors, or is it four? When you mix frequencies I would imagine you could arrive at all possible frequencies. I think you should drop the idea of waves with respect to frequency. If you observe a rainbow how many basic colors are there in the mix! The visible spectrum does not include "basic colors" It pretty much has all of them. Well, not Magenta. Is magenta a color? And when you talk "basic, are you talking Cyan, Magenta, Yellow, or Red, Green, Blue. It makes a difference. In a projector isn't there just three filters required for a movie in color? One thing you have to get into your mind is the idea of basic temperature and mass without energy. That would be a black body radiator at absolute 0. It's not very simple. Except for monochromatic light sources like lasers, light of any color contains multiple spectral lines. Sunlight or, for example, an incandescent bulb or red hot electric stove element contains a continuous spectrum, or effectively an infinite number of spectral lines or "colors". So you can't duplicate these with any finite number of spectral lines. The interesting thing is that with only three spectral lines (pure monochromatic colors) you can produce light that *looks* line nearly any color of light that's really made from many spectral lines. For example, (transparent) box A can contain an incandescent bulb whose light contains an infinite number of spectral lines or "colors", box B can produce light with only three spectral lines, and you won't be able to perceive the difference by eye if they're the right colors and brightnesses. This is the trick that makes color TV and color film work. It would be pretty easy to detect the difference with some simple tests, though. For example, the light from the two would look like different colors after passing through various color filters. Or pass the lights through a prism, and you'd see many more colors in the light from the incandescent bulb than the three-color source. But you can't make all perceived colors from any set of primary colors -- various choices of primary colors give you certain ranges of colors you can mimic. RGB and CMY of particular wavelengths give wide ranges, which is why they're common, but no choice can mimic all. I notice that some color printers have more ink colors, which I assume allows an even wider range. Creating light by combining colors is a different process than filtering white light by subtracting colors or letting only certain colors through. So different primary color sets are required. It's a fascinating topic, and yet another example of how our eyes deceive us. Roy Lewallen, W7EL |
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Cecil Moore wrote:
Jim, if you want to retain one iota of respect, please present a technical argument to refute what I have asserted. Sorry OM, you haven't proven your argument. You've provided no substantive data, and have shown nothing that indicates that this coil would conduct surface waves or behave as a tightly wound slow wave structure. It that's a Tesla coil, then so is any other coil. I'm just stating the obvious here. ac6xg |
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Jim Kelley wrote:
I'm just stating the obvious here. One lurker stated the obvious in an email to me. "It seems these guys will argue that black is white if it's you that is saying white is white!" The 75m Texas Bugcatcher loading coil satisfies the boundary conditions given for a slow-wave structure. What is obvious is that you and others absolutely refuse to engage in any technical argument concerning the subject. It is indeed obvious why you refuse to do so. Jim, I ask you again: How can one possibly use the following current as reported by EZNEC to measure the delay through a wire or through a loading coil? EZNEC+ ver. 4.0 1/4WL vertical 5/7/2009 5:34:16 PM --------------- CURRENT DATA --------------- Frequency = 7.29 MHz Wire No. 1: Segment Conn Magnitude (A.) Phase (Deg.) 1 Ground 1 0.00 2 .97651 -0.42 3 .93005 -0.83 4 .86159 -1.19 5 .77258 -1.50 6 .66485 -1.78 7 .54059 -2.04 8 .40213 -2.28 9 .25161 -2.50 10 Open .08883 -2.71 Your silence on the subject has so far been deafening. How do you explain Roy's (w7el) assertion at: http://www.w8ji.com/agreeing_measurements.htm "As described in my posting on rraa of November 11, the inductor "replaces" about 33 electrical degrees of the antenna." w8ji's measurement was a 3 nS delay. If an EM wave can travel through 33 degrees in 3 nS at 4 MHz, it is traveling considerably faster than the speed of light which is entirely possible with the lumped- circuit model. How do you explain that? -- 73, Cecil, IEEE, OOTC, http://www.w5dxp.com |
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Cecil Moore wrote:
Jim, I ask you again: How can one possibly use the following current as reported by EZNEC to measure the delay through a wire or through a loading coil? Ask as many times as you like. You're asking me explain how to use a printout from a computer program to measure current. The question makes no sense, Cecil. What I'd like to know is how is one supposed to respond to such nonsense. If what you want to know is how to measure current on a coil, I suggest that you need to build a current probe. Ask W8JI about it. According to your reference, the Corum paper, you would then plot current as a function of position along the axis of the helix. From that one can determine the axial length of the standing wave pattern - the length of the wave, so to speak. Given the frequency and the wavelength, one can easily arrive at the propagation velocity. If you need help with it, good luck. ac6xg |
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Jim Kelley wrote:
Cecil Moore wrote: Jim, if you want to retain one iota of respect, please present a technical argument to refute what I have asserted. Sorry OM, you haven't proven your argument. You've provided no substantive data, and have shown nothing that indicates that this coil would conduct surface waves or behave as a tightly wound slow wave structure. It that's a Tesla coil, then so is any other coil. I'm just stating the obvious here. ac6xg Cecil's using the old "You cain't prove it ain't" argument. Where has that come up before? 73, Tom Donaly, KA6RUH |
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Cecil Moore wrote:
Tom Donaly wrote: In the early '90's you hadn't come up with your ideas yet. How could Balanis agree with you before the fact? Again, nice try. On the contrary, in the early 90's I had not published my ideas yet. Dr. Balanis helped me to develop the very ideas that I have published and he agreed with them. Come up with some evidence that makes sense concerning your ideas and we can talk. I have presented my evidence long ago and you have ignored it in favor of ad hominem attacks. I cannot recall a single technical argument from you. For all I know, you are an 8 year old brat with access to his mother's computer. I would like nothing better than to engage in a real technical argument with you. You can start by producing technical arguments against the information on my web page. If you have EZNEC, you can verify everything I say by downloading the EZNEC files at: http://www.w5dxp.com/current2.htm Cecil, people have tried technical arguments on you for years, to no avail. Most have given up in disgust. Roy even plonked you. If Roy and Tom Rauch couldn't make you see reason, no one can. As for Balanis agreeing with you, that's pretty funny. 73, Tom Donaly, KA6RUH |
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On May 7, 2:31*pm, Cecil Moore wrote:
Art Unwin wrote: But Cecil the Bugcatcher does not conform with Maxwell's laws In what way does a Bugcatcher not conform with Maxwell's equations? In "Fields and Waves ...", Ramo and Whinnery give the actual Maxwell equations for a loading coil. -- 73, Cecil, IEEE, OOTC, *http://www.w5dxp.com I looked up the references and here are my comments 1 a helical is not in a state of equilibrium 2 A radiator that is not a WL or multiple thereof is not in equilibrium 3 It refered to boundary laws and then mis used them. 4 The beginning was littered with "assume" and terms of" Aproximation" 5 It then went on to change the configuration of a helix to a configuration that he thinks he has solved when using the approximations. He also assumed that the speed of light could be exceeded 6 I saw no evidence of accounting for the flux in a clockwise versus a counterclockwise action tho apparently he made assumptions that circular motion was zero. 7Frankly Cecil he knew what answer was to be accepted by reviwing Krauss's work and devised his mathematics accordingly 8 Krauss's work was on the subject of a helical that was not in equilibrium which thus forced him to include the helix angle which also is nowhere to be seen in Maxwells laws. The reference he used is not credible but name dropping of those that he agrees with is a confidence builder for those you judge plagurism as being with co believers. This is the same as those who defined light as a wave where academics followed with smiles and without question. It all still comes back to the fact that in boundary laws the contents must be in equilibrium and nothing about your antennamatches that requirement Sorry about that Cecil No harm meant Art |
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On May 7, 9:16*pm, Art Unwin wrote:
On May 7, 2:31*pm, Cecil Moore wrote: Art Unwin wrote: But Cecil the Bugcatcher does not conform with Maxwell's laws In what way does a Bugcatcher not conform with Maxwell's equations? In "Fields and Waves ...", Ramo and Whinnery give the actual Maxwell equations for a loading coil. -- 73, Cecil, IEEE, OOTC, *http://www.w5dxp.com I looked up the references and here are my comments 1 a helical is not in a state of equilibrium 2 A radiator that is not a WL or multiple thereof is not in equilibrium 3 It refered to boundary laws and then mis used them. 4 The beginning was littered with "assume" and terms of" Aproximation" 5 It then went on to change the configuration of a helix to a configuration that he thinks he has solved when using the approximations. He also assumed that the speed of light could be exceeded 6 I saw no evidence of accounting for the flux in a clockwise versus a counterclockwise action tho apparently he made assumptions that circular motion was zero. 7Frankly Cecil he knew what answer was to be accepted by reviwing Krauss's work and devised his mathematics accordingly 8 Krauss's work was on the subject of a helical that was not in equilibrium which thus forced him to include the helix angle which also is nowhere to be seen in Maxwells laws. The reference he used is not credible but name dropping of those that he agrees with is a confidence builder for those you judge plagurism as being with co believers. This is the same as those who defined light as a wave where academics followed with smiles and without question. It all still comes back to the fact that in boundary laws the contents must be in equilibrium and nothing about your antennamatches that requirement Sorry about that Cecil No harm meant Art Oooops, I forgot the real biggy. You mentioned that a spark was emmited from the end of your antenna. I am sure you are aware that this is symbolic of end effect. Maxwell has no equation for end effect ! Nor did he see the need to account for that force. Why? Because that is representitive of a radiator that is NOT in equilibrium. It takes a circuit of 1 WL or multiple there of to reach the state of equilibrium. This is why the radiator at Quito Equador was changed to a quad ala 1 WL just to get rid of "end effect" which is of no help in terms of drectivity just a waste of radiation energy. I will say it again, boundary laws as does all the laws of our Universe demand that a state of equilibrium is present such that it meets Newtons law that "every action has an equal and opposite reaction" which in mathematical terms for the boundary aproach is that all forces summed equals zero. I feel that this debate has now come to an end. Maxwell's laws are not applicable or valid when a radiator is not in equilibrium. And resonance does not equate to equilibrium because end effect is not present and thus not applicable with respect to Maxwell. Best regards Art' |
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On May 7, 1:35*pm, Roy Lewallen wrote:
Michael Coslo wrote: Art Unwin wrote: I don't know about waves but my understanding is that all colors come from the mixing *of the three basic colors, or is it four? When you mix frequencies I would imagine you could arrive at all possible frequencies. *I think you should drop the idea of waves with respect to frequency. If you observe a rainbow how many basic colors are there in the mix! The visible spectrum does not include "basic colors" It pretty much has all of them. Well, not Magenta. Is magenta a color? And when you talk "basic, are you talking Cyan, Magenta, Yellow, or Red, Green, Blue. It makes a difference. In a projector isn't there just three filters required for a movie in color? One thing you have to get into your mind is the idea of basic temperature and mass without energy. That would be a black body radiator at absolute 0. It's not very simple. Except for monochromatic light sources like lasers, light of any color contains multiple spectral lines. Sunlight or, for example, an incandescent bulb or red hot electric stove element contains a continuous spectrum, or effectively an infinite number of spectral lines or "colors". So you can't duplicate these with any finite number of spectral lines. The interesting thing is that with only three spectral lines (pure monochromatic colors) you can produce light that *looks* line nearly any color of light that's really made from many spectral lines. For example, (transparent) box A can contain an incandescent bulb whose light contains an infinite number of spectral lines or "colors", box B can produce light with only three spectral lines, and you won't be able to perceive the difference by eye if they're the right colors and brightnesses. This is the trick that makes color TV and color film work. It would be pretty easy to detect the difference with some simple tests, though. For example, the light from the two would look like different colors after passing through various color filters. Or pass the lights through a prism, and you'd see many more colors in the light from the incandescent bulb than the three-color source. But you can't make all perceived colors from any set of primary colors -- various choices of primary colors give you certain ranges of colors you can mimic. RGB and CMY of particular wavelengths give wide ranges, which is why they're common, but no choice can mimic all. I notice that some color printers have more ink colors, which I assume allows an even wider range. Creating light by combining colors is a different process than filtering white light by subtracting colors or letting only certain colors through. So different primary color sets are required. It's a fascinating topic, and yet another example of how our eyes deceive us. Roy Lewallen, W7EL Further on this topic: one of the interesting things that comes up when you look into "white" LED or fluorescent lights is that they pretty much all have "holes" in their spectra. That is, the spectrum they emit isn't continuous and the same shape as with light from an incandescent source (including sunlight). The result is that some things which reflect strongly over a narrow spectral band and much less outside that band will look funny under such an LED or fluorescent light. The light reflected by the object under such a light doesn't have the "right" spectral shape. But it's something that the lamp manufacturers are paying special attention to these days, and you can find ratings on many bulbs about how good a job they do at color rendering. Cheers, Tom |
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Jim Kelley wrote:
Ask as many times as you like. You're asking me explain how to use a printout from a computer program to measure current. The question makes no sense, Cecil. What I'd like to know is how is one supposed to respond to such nonsense. Jim, I'm sorry that you are not capable of converting the EZNEC printout into a graph. Would you like me to show you how to do it? If what you want to know is how to measure current on a coil, I suggest that you need to build a current probe. Ask W8JI about it. According to your reference, the Corum paper, you would then plot current as a function of position along the axis of the helix. From that one can determine the axial length of the standing wave pattern - the length of the wave, so to speak. Given the frequency and the wavelength, one can easily arrive at the propagation velocity. If you need help with it, good luck. You're preaching to the choir, Jim. You and I know that the phase information for a standing wave is contained in the amplitude and the phase relative to time is constant at all points on the antenna for any particular time. What you should be doing is explaining that to w7el and w8ji because they don't seem to understand that the current phase in standing wave antennas does NOT change with distance. Here's an earlier question that you guys ignored. Given a 1/2WL dipole with current probes at x and y: ---------------------------fp--------x--------y--------- points x and y are 30 degrees apart. What will be the difference between the phase of the current at x and the phase of the current at y? EZNEC says ~1 degree. How can current phase change by one degree in 30 degrees of wire? -- 73, Cecil, IEEE, OOTC, http://www.w5dxp.com |
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Tom Donaly wrote:
Cecil's using the old "You cain't prove it ain't" argument. I have presented my arguments. Nobody has refuted them technically. All the objections have been ad hominem or based on false premises. A 75m Texas Bugcatcher coil meets the Corum test for a helical sheath. That test is on page 4 of: http://www.ttr.com/TELSIKS2001-MASTER-1.pdf "... is valid for helices with 5ND^2/WLo 1 where N is the TPI and D is the diameter." That figure is 0.244 1 for the 75m Texas Bug Catcher used on 4 MHz. 5*4*6^2/2952 = 0.244 So all you guys have to do to shoot down my analysis is to prove that 0.244 is not less than one. -- 73, Cecil, IEEE, OOTC, http://www.w5dxp.com |
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Tom Donaly wrote:
If Roy and Tom Rauch couldn't make you see reason, no one can. Roy and Tom are the ones committing the technical blunder of trusting their phase measurements using a current that doesn't change phase relative to the source phase anywhere up and down the thin-wire 1/2WL dipole. Now you and others are helping them to sandbag their technical myths and hoodwink the unwashed masses. If that's what you want for a reputation, be my guest. EZNEC agrees that the relative phase of the current on a standing wave antenna doesn't change anywhere on a 1/2WL thin-wire dipole so it cannot be used to measure the phase shift through the wire. EZNEC says that the phase of the current on a standing wave antenna changes about 1 degree for every 30 degrees of antenna wire. Roy and Tom would have to admit that is considerably faster than the speed of light. Of course, that's exactly what the lumped-circuit model presupposes - instantaneous propagation through the lumped-inductor. Since that current cannot even be used to determine the phase shift through the antenna wire, how can anyone honestly assert that it can be used to determine the phase shift through a loading coil? -- 73, Cecil, IEEE, OOTC, http://www.w5dxp.com |
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"Art Unwin" wrote in message ... I feel that this debate has now come to an end. Maxwell's laws are not applicable or valid when a radiator is not in equilibrium. And resonance does not equate to equilibrium because end effect is not present and thus not applicable with respect to Maxwell. so when can we expect the publication of "art's equations" to fill this gap? |
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"Art Unwin" wrote in message ... I looked up the references and here are my comments 1 a helical is not in a state of equilibrium of course it is, there is an equals in the equation so it must be in 'equal'ibrium according to your definition. 2 A radiator that is not a WL or multiple thereof is not in equilibrium my half wave radiator, and my infinitesimal dipole both have equals signs in their equations to they must be in your state of 'equal'ibrium also! |
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Roy Lewallen wrote:
It's not very simple. Except for monochromatic light sources like lasers, light of any color contains multiple spectral lines. Sunlight or, for example, an incandescent bulb or red hot electric stove element contains a continuous spectrum, or effectively an infinite number of spectral lines or "colors". So you can't duplicate these with any finite number of spectral lines. The interesting thing is that with only three spectral lines (pure monochromatic colors) you can produce light that *looks* line nearly any color of light that's really made from many spectral lines. AHa! I was going to write about the emulation of color, but wasn't sure if I'd just confuse things. But you've done a good job describing it, so here we are. So called "Lippmann" emulsions can do color correctly, but they work on a wavefront basis instead of combining colors.(the individual particles of silver are extremely small, so they can do that) A color Lippmann image can be gorgeous, but they are really difficult to make, so are more of a curiosity than anything else. which is why they're common, but no choice can mimic all. I notice that some color printers have more ink colors, which I assume allows an even wider range. That's a big part of it. Inkjets have some mechanical issues too, such as the best looking colors might not last very long, or a good long lasting color might be hard to squeeze through the little jets. SO we get stuck with multiple color cartridges. But for the purposes at hand, the color perception issue is the big one, and the others can be ignored. - 73 de Mike N3LI - |
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On May 8, 7:34*am, "Dave" wrote:
"Art Unwin" wrote in message ... I feel that this debate has now come to an end. Maxwell's laws are not applicable or valid when a radiator is not in equilibrium. And resonance does not equate to equilibrium because *end effect is not present and thus not applicable with respect to Maxwell. so when can we expect the publication of "art's equations" to fill this gap? David All hams armed with the above fact can now pursue experimentation with abandon for themselves. It will be decades before science can accept change. So for those hams willing to accept change and become do'ers, that is very important to me, the lack of sun spots will not push them away from the hobby. I am old and not good looking but like Susan Boyle what I am sharing with all will last a life time. For the "gurus" the next challenge is to devise an equation that will account for all forces involved in the production of "end effect" that will withstand rigourous examination. In other words David, nasty words with contempt have soured my desire to share for the moment Regards Art...,..xg In the corner of every battle field there lies a piece of England But for me life, which is good, goes on |
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"Art Unwin" wrote in message ... In other words David, nasty words with contempt have soured my desire to share for the moment I don't know weather to be sad that i'll miss your great words of wisdom, or happy that your gibberish may be quelled for a while. Spring is here, so i have my own REAL antenna work to do, so i guess i really don't need your imaginary stuff anyway. |
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On May 8, 11:59*am, "Dave" wrote:
"Art Unwin" wrote in message ... In other words David, nasty words with contempt have soured my desire to share for the moment I don't know weather to be sad that i'll miss your great words of wisdom, or happy that your gibberish may be quelled for a while. *Spring is here, so i have my own REAL antenna work to do, so i guess i really don't need your imaginary stuff anyway. Atta boy, Keep using that slide rule from your school days, there is absolutely no reason why you should change and update |
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Still here, and still trying to strip away the personal attacks to try
to understand the various underlying technical opinions! When I model a "bugcatcher" plus stinger using EZNEC, I see significantly less current at the top of the coil compared with the bottom of the coil. I also see a slight increase in current part way up the coil before it then decreases towards the top. In reply to an earlier question of mine, Roy assured me that this current distribution was "real" and not some problem that EZNEC has modelling this arrangement. I have two questions if I may: 1) Cecil: I believe I understand how the Corum transmission line model accounts nicely for the reduced current at the top of the coil. Does it also account for the slight increase in current a short way from the bottom? 2) Jim, Tom, Roy (and any others): It appears you think the Corum model is flawed, or not appropriate to the "bugcatcher". What I've not yet understood is what alternative model you are advocating which would match the EZNEC results more closely than the Corum model. I've heard at least Roy say that a lumped-inductor model is inappropriate, but I don't think I've yet heard any other model proposed. Perhaps I missed it? Regards, Steve G3TXQ |
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On May 8, 9:01*am, Michael Coslo wrote:
Roy Lewallen wrote: It's not very simple. Except for monochromatic light sources like lasers, light of any color contains multiple spectral lines. Sunlight or, for example, an incandescent bulb or red hot electric stove element contains a continuous spectrum, or effectively an infinite number of spectral lines or "colors". So you can't duplicate these with any finite number of spectral lines. The interesting thing is that with only three spectral lines (pure monochromatic colors) you can produce light that *looks* line nearly any color of light that's really made from many spectral lines. * * * * AHa! I was going to write about the emulation of color, but wasn't sure if I'd just confuse things. But you've done a good job describing it, so here we are. * * * * So called "Lippmann" emulsions can do color correctly, but they work on a wavefront basis instead of combining colors.(the individual particles of silver are extremely small, so they can do that) A color Lippmann image can be gorgeous, but they are really difficult to make, so are more of a curiosity than anything else. which is why they're common, but no choice can mimic all. I notice that some color printers have more ink colors, which I assume allows an even wider range. That's a big part of it. Inkjets have some mechanical issues too, such as the best looking colors might not last very long, or a good long lasting color might be hard to squeeze through the little jets. SO we get stuck with multiple color cartridges. But for the purposes at hand, the color perception issue is the big one, and the others can be ignored. * * * * - 73 de Mike N3LI - But guys you are jumping to fast with your statements and conclusions. Go back to the basics and start afresh. Remember we are seeing color as representitive of temperature and the mass and potential energy that is affected by a particles passage thru a medium. Thus the temperature spectrum compares with the total color spectrum which covers all the frequencies involved. Thus a clump or cluster of particles entering a different medium represents all frequencies and dependent on the dispelled kinetic energy of each with respect to their mass covers all the colors possible. In other words a single particle disposed to the red spectrum can supply all the different hues of red all of which are dependent on the mass, expended kinetic energy, and the ratio of expended energy to potential energy when encountering a change of medium. A blacksmith does this all the time when reviewing color on the impact of his hammer without thinking. Even the X ray frequencies have color Art |
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