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#11
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![]() Cecil Moore wrote: Jim Kelley wrote: I now acknowledge knowing of two such people who believe in energy in nonexistent waves. Your attempt at obfuscation is well known to all, Jim. It is your propensity for baseless accusation that is well known around here, Cecil. Two canceled waves cease to exist but the energy in the two waves that canceled cannot cease to exist. I'm sorry you're having so much trouble understanding such a simple idea. It really does turn you surly. The waves don't 'stop existing'. Given the conditions, they can never exist. In the steady state, things don't first do one thing, and then some time later do something else. ac6xg |
#12
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Jim Kelley wrote:
Two canceled waves cease to exist but the energy in the two waves that canceled cannot cease to exist. I'm sorry you're having so much trouble understanding such a simple idea. The idea that canceled reflections never existed in the first place is not a simple one. If they never existed in the first place, there is no reason to ever try to cancel them because there was never anything to cancel. In effect, you are saying the lack of reflections causes the reflections never to have existed. Not only is that confusing cause and effect but it also introduces time travel. "If you went back in time and killed your grandfather before you were born, you would cease to exist." But if you never existed, who killed your grandfather? That's the exact logic that you are using. It really does turn you surly. The waves don't 'stop existing'. Yes, they do. They stop existing in their original direction of travel. A reflected power meter proves it. A forward power meter proves that the energy that existed in the canceled waves joined the forward wave. What is it about the Melles- Groit and FSU redistribution of energy explainations that you don't understand? Given the conditions, they can never exist. If reflections never exist, there is no need for a non- reflective coating, is there? People who buy non-reflective picture frames are wasting their money since the reflections never exist. What is it about the Melles-Groit and FSU explainations about redistribution of energy from the canceled waves that you don't understand? In the steady state, things don't first do one thing, and then some time later do something else. I've explained this before. Wave cancellation is a continuous steady-state process. Ptot = P1 + P2 - 2*SQRT(P1*P2) = 0 is a continuous process. Every dt, waves P1 and P2 are in the process of canceling each other during steady-state. -- 73, Cecil http://www.w5dxp.com |
#13
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Richard Clark wrote:
"Perhaps others will join in." Haven`t read all the postings and don`t propose to contradict anyone. Radio waves are energy in motion. They continue so long as their supply does. The same energy can`t be in two places at once. Energy can be redirected. Practical antennas are an example. The only non-directional antenna is the imaginary isotropic radiator which if it were constructed would by definition produce waves of equal strength in all directions. Terman says on page 871 of his 1955 opus: "Thus a gain of 4 (or 6dB) means that the power intensity is 4 times as great (field intensity twice as great) as would be the case if the radiator in question were an isotropic antenna radiating the same total power." The foregoing tells us power phased-out in some directions is redirected to a direction of maximum radiation. Constructive interference exactly equals destructive interference because a fixed amount of power is available and conservation of erergy must be satisfied. The same is true on a transmission line whose only possible directions are forward and reverse. Best regards, Richard Harrison, KB5WZI |
#14
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![]() Cecil Moore wrote: Jim Kelley wrote: I'm sorry you're having so much trouble understanding such a simple idea. The idea that canceled reflections never existed in the first place is not a simple one. Just cut the BS, Cecil. In order to prove your assertion you must first be able to describe how two co-linear, coherent waves that are 180 degrees out of phase at every point along their path and traveling in the same direction can under those circumstances at any time produce measureable energy. In addition, you must be able to measure it. Let me know when you do. ac6xg PS - I'd like to suggest that you ask Dr. Barrans to explain to you what 'Up + Down = Nothing' means. |
#15
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Jim Kelley wrote:
Just cut the BS, Cecil. In order to prove your assertion you must first be able to describe how two co-linear, coherent waves that are 180 degrees out of phase at every point along their path and traveling in the same direction can under those circumstances at any time produce measureable energy. In addition, you must be able to measure it. Let me know when you do. It is an indirect measurement, Jim. Given the s-parameter equation, b1 = s11*a1 + s12*a2 = 0, s11 is not zero, a1 is not zero, s12 is not zero, and a2 is not zero. Although HP cannot measure those quantities either, they tell us that |s11*a1|^2 is in watts, e.g. 100 watts. They tell us that |s12*a2|^2 is in watts, e.g. 100 watts. When all energy is accounted for, it is obvious that those 200 watts are no longer in the direction of the source but have changed direction toward the load. This ain't rocket science. If reflections are eliminated toward the source by wave cancellation, the reflected energy is redistributed back toward the load just as explained on the Melles-Groit and FSU web pages. If it weren't headed for the source in the first place, they wouldn't say it was "REDISTRIBUTED". If 200 joules/sec disappear toward the source and there are only two directions in a transmission line, do you really want to tell us that you can't figure out in which direction those joules go? Do you need help from my 10 year old grandson? You clearly fail to understand the process defined by the wave reflection distributed network model. Until you are in a position to discredit that model, you are just blowing smoke. -- 73, Cecil http://www.w5dxp.com |
#16
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![]() Cecil Moore wrote: Jim Kelley wrote: Just cut the BS, Cecil. In order to prove your assertion you must first be able to describe how two co-linear, coherent waves that are 180 degrees out of phase at every point along their path and traveling in the same direction can under those circumstances at any time produce measureable energy. In addition, you must be able to measure it. Let me know when you do. It is an indirect measurement, Jim. :-) Sure thing. Like I said, let me know when you measure energy in the canceled waves. ac6xg |
#17
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Jim Kelley wrote:
Cecil Moore wrote: It is an indirect measurement, Jim. :-) Sure thing. Like I said, let me know when you measure energy in the canceled waves. Let me know when you figure out an explanation for the reversal of momentum in those reflected waves. So far, you have absolutely refused to provide any explanation. -- 73, Cecil http://www.w5dxp.com |
#18
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![]() Cecil Moore wrote: Jim Kelley wrote: Cecil Moore wrote: It is an indirect measurement, Jim. :-) Sure thing. Like I said, let me know when you measure energy in the canceled waves. Let me know when you figure out an explanation for the reversal of momentum in those reflected waves. So far, you have absolutely refused to provide any explanation. The momentum in reflected waves changes direction upon reflection. What part of that do you need to have explained? So, back to you. Let's hear more about your measurement of canceled waves. ac6xg |
#19
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Jim Kelley wrote:
The momentum in reflected waves changes direction upon reflection. What part of that do you need to have explained? What causes 100% reflection when the power reflection coefficient (reflectance) is only 0.5? -- 73, Cecil http://www.w5dxp.com |
#20
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Jim Kelley wrote:
Cecil Moore wrote: Jim Kelley wrote: Just cut the BS, Cecil. In order to prove your assertion you must first be able to describe how two co-linear, coherent waves that are 180 degrees out of phase at every point along their path and traveling in the same direction can under those circumstances at any time produce measureable energy. In addition, you must be able to measure it. Let me know when you do. It is an indirect measurement, Jim. :-) Sure thing. Like I said, let me know when you measure energy in the canceled waves. At the risk of being both a dullard and messing up all the fun, does not every destructive interference have to be balanced by a constructive interference, which in turn leads to a condition of "Okey dokey?" A canceled wave needs a reinforced wave, and then nothing is lost, nothing is gained. - 73 de Mike N3LI - |
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