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#1
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Coils and Transmission Lines.
To satisfy demands for disclosure of the source code of my programs I
have made the source code of program TRANCO_1 available from my website. It may be of interest to antagonists in the "current through coils" civil war. The source code text, which is almost readable using non-proportional spaced text readers, can be found in "Download Pascal source code from here" section on the Index page. ---- .................................................. .......... Regards from Reg, G4FGQ For Free Radio Design Software go to http://www.btinternet.com/~g4fgq.regp .................................................. .......... |
#2
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Coils and Transmission Lines.
Reg Edwards wrote:
It may be of interest to antagonists in the "current through coils" civil war. The nature of traveling wave current and standing wave current is different. Does your program take that into account? The "current through coils" argument boils down to the ones who understand standing wave currents in a standing wave antenna and those who refuse to take the time to understand. Quoting "Optics", by Hecht: "E(x,t) = 2Eo*sin(kx)*cos(wt) This is the equation for a STANDING or STATIONARY WAVE, as opposed to a traveling wave (Fig. 7.10). Its profile does not move through space. ... [The phase] doesn't rotate at all, and the resultant wave it represents doesn't progress through space - it's a standing wave." Until the gurus take the time to understand the nature of standing waves in standing waves antennas, they will keep committing the same mental blunders over and over. -- 73, Cecil http://www.qsl.net/w5dxp |
#3
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Coils and Transmission Lines.
Cecil Moore wrote:
Reg Edwards wrote: It may be of interest to antagonists in the "current through coils" civil war. The nature of traveling wave current and standing wave current is different. Does your program take that into account? The "current through coils" argument boils down to the ones who understand standing wave currents in a standing wave antenna and those who refuse to take the time to understand. Quoting "Optics", by Hecht: "E(x,t) = 2Eo*sin(kx)*cos(wt) This is the equation for a STANDING or STATIONARY WAVE, as opposed to a traveling wave (Fig. 7.10). Its profile does not move through space. ... [The phase] doesn't rotate at all, and the resultant wave it represents doesn't progress through space - it's a standing wave." Until the gurus take the time to understand the nature of standing waves in standing waves antennas, they will keep committing the same mental blunders over and over. Hecht forgot to put the phase difference in his formula. It's no wonder there's no phase information in your standing waves, Cecil, Hecht left it out. Not only that, but where did he get the idea that it was sin(kx) instead of cos(kx). I understand Hecht is a good old boy, but I'd like to see his derivations. 73, Tom Donaly, KA6RUH |
#4
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Coils and Transmission Lines.
Tom Donaly wrote:
Hecht forgot to put the phase difference in his formula. It's no wonder there's no phase information in your standing waves, Cecil, Hecht left it out. You are mistaken. If Hecht left it out then so did Gene Fuller. I suggest you listen to Gene when he says: Regarding the cos(kz)*cos(wt) terms in the standing wave equation: Gene Fuller, W4SZ wrote: In a standing wave antenna problem, such as the one you describe, there is no remaining phase information. Any specific phase characteristics of the traveling waves died out when the startup transients died out. Phase is gone. Kaput. Vanished. Cannot be recovered. Never to be seen again. The only "phase" remaining is the cos (kz) term, which is really an amplitude description, not a phase. Not only that, but where did he get the idea that it was sin(kx) instead of cos(kx). I understand Hecht is a good old boy, but I'd like to see his derivations. Apparently, you are ignorant of the difference in conventions between optics and RF engineering. In optics, there is no current so there is no current changing phase at an open circuit. In optics, the M-field changes directions but not phase. In RF engineering, a change in direction of the H-field is considered to be a 180 degree phase shift. Both conventions are correct as long as one understands them. Your strange statement about Hecht above just proves your ignorance. -- 73, Cecil http://www.qsl.net/w5dxp |
#5
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Coils and Transmission Lines.
Cecil Moore wrote:
Tom Donaly wrote: Hecht forgot to put the phase difference in his formula. It's no wonder there's no phase information in your standing waves, Cecil, Hecht left it out. You are mistaken. If Hecht left it out then so did Gene Fuller. I suggest you listen to Gene when he says: Regarding the cos(kz)*cos(wt) terms in the standing wave equation: Gene Fuller, W4SZ wrote: In a standing wave antenna problem, such as the one you describe, there is no remaining phase information. Any specific phase characteristics of the traveling waves died out when the startup transients died out. Phase is gone. Kaput. Vanished. Cannot be recovered. Never to be seen again. The only "phase" remaining is the cos (kz) term, which is really an amplitude description, not a phase. Not only that, but where did he get the idea that it was sin(kx) instead of cos(kx). I understand Hecht is a good old boy, but I'd like to see his derivations. Apparently, you are ignorant of the difference in conventions between optics and RF engineering. In optics, there is no current so there is no current changing phase at an open circuit. In optics, the M-field changes directions but not phase. In RF engineering, a change in direction of the H-field is considered to be a 180 degree phase shift. Both conventions are correct as long as one understands them. Your strange statement about Hecht above just proves your ignorance. Whatever. I'd still like to see his derivations. In your case, you're using the wrong equation anyway. What you really want is Beta*l, or the radian length of your transmission line. You can get that if you know, or can measure the usual parameters in the transmission line impedance equation, using that equation to solve for Beta*l. That won't prove your theory because you still haven't shown that any one transmission line model is unique in terms of substituting for your coil, but at least it'll give you something to do. 73, Tom Donaly, KA6RUH |
#6
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Coils and Transmission Lines.
Tom Donaly wrote:
Whatever. I'd still like to see his derivations. "Optics", by Hecht, 4th edition, page 289. The intensity of a light beam is associated with the E-field so Hecht's equations are in relation to the E-field. Speaking of the light standing wave: "The composite disturbance is then: E = Eo[sin(kt+wt) + sin(kt-wt)] Applying the indentity sin A + sin B = 2 sin 1/2(A+B)*cos 1/2(A-B) E(x,t) = 2*Eo*sin(kx)*cos(wt)" Hecht says the standing wave "profile does not move through space". I have said the RF standing wave current profile does not move through a wire. Hecht says the standing wave phasor "doesn't rotate at all, and the resultant wave it represents doesn't progress through space - it's a standing wave." I have said the same thing about the RF standing wave current phasor. Hecht says the standing wave transfers zero net energy. I have said the same thing about RF standing waves. -- 73, Cecil http://www.qsl.net/w5dxp |
#7
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Coils and Transmission Lines.
Cecil Moore wrote:
Tom Donaly wrote: Whatever. I'd still like to see his derivations. "Optics", by Hecht, 4th edition, page 289. The intensity of a light beam is associated with the E-field so Hecht's equations are in relation to the E-field. Speaking of the light standing wave: "The composite disturbance is then: E = Eo[sin(kt+wt) + sin(kt-wt)] Applying the indentity sin A + sin B = 2 sin 1/2(A+B)*cos 1/2(A-B) E(x,t) = 2*Eo*sin(kx)*cos(wt)" Hecht says the standing wave "profile does not move through space". I have said the RF standing wave current profile does not move through a wire. Hecht says the standing wave phasor "doesn't rotate at all, and the resultant wave it represents doesn't progress through space - it's a standing wave." I have said the same thing about the RF standing wave current phasor. Hecht says the standing wave transfers zero net energy. I have said the same thing about RF standing waves. If it's a solution to the wave equation it's o.k., Cecil, but Hecht is still not using the case where there is a phase difference between the two waves. If it isn't in the original equation it won't be in the final version since they're just two ways of saying the same thing. That's fine because it's the wrong equation anyway for what you want, which involves impedances and length, which you probably don't want to deal with because you're probably under the impression they're just virtual and not real, and so not worthy of inclusion in your theory. 73, Tom Donaly, KA6RUH |
#8
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Coils and Transmission Lines.
"Cecil Moore" wrote in message
Until the gurus take the time to understand the nature of standing waves in standing waves antennas, they will keep committing the same mental blunders over and over. -- 73, Cecil http://www.qsl.net/w5dxp More astonishing than that, Until the "gurus" put their finger on the coil, or aquarium thermometer, or RF ammeter, or infrared scope and see that the loading coil (in a typical quarter wave resonant whip) is heating up at the bottom, being the reality that defies their "scientwific theories why it shouldn't" - they will keep committing the same mental blunders over and over. What's next? There is less current in a wire (coil) where wire (coil) gets hotter? Let the games begin! Thermometers don't lie, meters don't lie, even EZNEC shows it! So wasaaaaap? Yuri, K3BU |
#9
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Coils and Transmission Lines.
Yuri Blanarovich wrote: More astonishing than that, Until the "gurus" put their finger on the coil, or aquarium thermometer, or RF ammeter, or infrared scope and see that the loading coil (in a typical quarter wave resonant whip) is heating up at the bottom, being the reality that defies their "scientwific theories why it shouldn't" - they will keep committing the same mental blunders over and over. Yuri, No one I have seen has every said one tuern can't get hotter than another turn in a loading coil. For example, I can take a piece of airdux and short a single turn anywhere in the coil. That turn and the turns around it will get very hot, often even melting the form and discoloring the wire, even with modest power applied in a resoant circuit. I had my 75 watt Novice rig melt miniductor in certain spots way back in the very early 60's. The problem is wild theories are created from small grains of truth or factoids. It is the wild theories that people question. In an effort to support the wild claims, there seems to be an effort to dismiss anything but the wild theories. Here is how it goes: 1.) My Hustler antenna loading coil (known to be a poor electrical design) melted the heatshrink at the bottom 2.) This must be becuase there is only high current at the bottom of every loading coil. 3.) This must be because the standing waves on the antenna all wind up in the loading coil. 4.) This must mean all loading coils act just like they are the x degrees of antenna they replace. 5.) This is why, no matter what we do with loading coil Q, efficiency doesn't change much. 6.) We will write a IEEE paper about this astounding fact, since all the texbooks about loading coils or inductors in general must be wrong 7.) Anyone who point out it is imperfections in the design of the system that cause this must be wrong, since I saw the coil get hot 8.) Anyone who disagrees with me must think himself a guru, and be incapable of learning or understanding how things work 9.) I know all this because the bottom of the coil gets hot in my antenna What's next? There is less current in a wire (coil) where wire (coil) gets hotter? Thermometers don't lie, meters don't lie, even EZNEC shows it! So wasaaaaap? It's all been explained over and over again. If the termination impedance of the coil is very high compared to shunting impedances inside the coil to the outside world, a coil can have phase shift in current at each terminal and it can have uneven current distribution. This is not caused by standing waves or "electrical degrees" the coil replaces, but rather by the displacement currents which can provide a path for the through currents. Reg actually explained this very well, as has Roy, Tom D, Gene, Tom ITM, Ian, and a half dozen others. The reason you keep beating your head against the wall is you want to think the conclusions you formed were correct. If I wanted to design a loading coil that has virtually 100% current taper, I could. If I wanted to design one with virtually no taper, I could. I could actually have an antenna of a fixed height and by making various styles of loading coils go anywhere from nearly uniform distribution at each end of the coil to some significant taper. The problem is Cecil attributes it all to standing waves, and not to the inductor's design. You seem to be doing the same. Since we won't agree with your wrong theories, you then conclude we are saying step one is wrong and you never saw what you saw. Step one is fine. Step two is where everything you say falls apart. 73 Tom |
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