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#421
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Current across the antenna loading coil - from scratch
On Wed, 12 Apr 2006 19:04:18 GMT, Cecil Moore
wrote: Richard Clark wrote: Cecil Moore wrote: When trimming one line attributes the posting to a completely different person, that is a clear violation. Is that an RMS Net violation of the superposition of all violations considererd? Tsk, tsk, Richard, are you defending false attributions? Tsk Tsk? to what accuracy ±59%? |
#422
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Current across the antenna loading coil - from scratch
On Wed, 12 Apr 2006 19:02:56 GMT, Cecil Moore
wrote: Richard Clark wrote: Cecil Moore wrote: That's a legal term under Texas law. Oh, must be Phil then, Herr Doktor never explains anything. I thought the explanation was obvious. If I am going to get sued because of false attributions, I need a paper trail and proof that I objected to those false attributions. Paper trail? Phil, push over those stacks of "research" and fire up the Xerox! |
#423
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Current across the antenna loading coil - from scratch
Roy Lewallen wrote:
Agreed, it's not quite stated as such. Here are some statements which were made: From your web page http://www.k3bu.us/loadingcoils.htm, in bold type: "In summary: The current in a typical loading coil in the shortened antennas drops across the coil roughly corresponding to the segment of the radiator it replaces." By Cecil, on March 5, on this newsgroup: The coil occupies roughly the same number of degrees of the antenna as the wire it replaces. Roy, maybe you need to learn the definition of "roughly". It is certainly not "exactly" as you are clutching at straws to imply. Why you need to change the definitions of words is obvious from your flawed arguments. Exactly what is it about "roughly" that you don't understand? It's getting muddier and muddier just what you mean by "replace". That meaning has never been in doubt. "Replace" has always meant bringing the necessary signals back into phase so the feedpoint impedance is purely resistive. You know perfectly well that it has never been about physical length or radiation. Those are just another two of your straw men. Your attempt to muddy those waters has been going on for years including your attempt to discredit the distributed network model in favor of the lumped circuit model. Hint: The distributed network model is a superset of the lumped circuit model. If you succeed in discrediting the distributed network model, you have automatically succeeded in discrediting the lumped circuit model. It's a lose-lose proposition for you. -- 73, Cecil http://www.qsl.net/w5dxp |
#424
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Current across the antenna loading coil - from scratch
Richard Clark wrote:
Paper trail? Phil, push over those stacks of "research" and fire up the Xerox! I am indeed printing out the postings just in case the false attributions result in a lawsuit against me. I can't afford not to be careful. -- 73, Cecil http://www.qsl.net/w5dxp |
#425
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Current across the antenna loading coil - from scratch
On Wed, 12 Apr 2006 19:24:27 GMT, Cecil Moore
wrote: Richard Clark wrote: Paper trail? Phil, push over those stacks of "research" and fire up the Xerox! I am indeed printing out the postings just in case the false attributions result in a lawsuit against me. I can't afford not to be careful. But you CAN afford to be paranoid? What a WUSS! |
#426
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Current across the antenna loading coil - from scratch
Richard Clark wrote:
But you CAN afford to be paranoid? What a WUSS! It doesn't cost anything to be paranoid. :-) -- 73, Cecil http://www.qsl.net/w5dxp |
#427
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Current across the antenna loading coil - from scratch
Cecil Moore wrote:
Roy, maybe you need to learn the definition of "roughly". It is certainly not "exactly" as you are clutching at straws to imply. Why you need to change the definitions of words is obvious from your flawed arguments. Exactly what is it about "roughly" that you don't understand? Cecil, Is 10 degrees of phase shift "roughly" equal to 75 degrees of phase shift? I don't think anyone is trying to nit-pick the numbers to a precision of several significant figures. A multiple of greater than 7 would seem to be just a bit outside the scope of "roughly". 73, Gene W4SZ |
#428
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Current across the antenna loading coil - from scratch
Ian White GM3SEK wrote:
Ian, I am leaving on a 6 state motorcycle trip and won't be back until Monday. I would like for you to answer this question while I am gone. I've heard that, while operating portable, if I attach a wire to my 75m mobile whip and run it up a tree, I will be able to make more contacts. So I attach a 1/4WL wire to the whip of my 75m mobile bugcatcher system. I decide to measure the current "into" the bottom of the coil and "out" of the top of the coil. To my utter amazement I measure 1.3 amps flowing "into" the bottom of the coil and 2.1 amps flowing "out" of the top of the coil. How does your lumped circuit theory explain that? Where is that extra 0.8 amps of current coming from? Please don't insult our intelligence by saying it cannot happen. It does happen. I suspect you are at a loss to explain it. -- 73, Cecil http://www.qsl.net/w5dxp |
#429
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Current across the antenna loading coil - from scratch
Gene Fuller wrote:
Is 10 degrees of phase shift "roughly" equal to 75 degrees of phase shift? Of course not. The 10 degrees of phase shift has already been proven to be wrong because of reflections within the coil. Why do you insist on bringing up old invalid data? Please note that *nobody* is alleging that the phase shift through a 75m bugcatcher coil is 75 degrees. That is just another one of your straw men. Now why don't you become a rational, ethical person and suggest a valid way of measuring the phase shift through a coil? Can you improve on my suggestion of yesterday? -- 73, Cecil http://www.qsl.net/w5dxp |
#430
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Current across the antenna loading coil - from scratch
Cecil Moore wrote:
Ian White GM3SEK wrote: Now what happens if the load is not exactly 50 ohms? If the feedline is 50 ohms, what happens is reflected energy that is easily visible using a TDR, time domain reflectometer. One is that if the meter scale says "power", then there genuinely are forward and reflected traveling waves of power on the line. In the "93 - 23 = 70W" example, the belief is that there genuinely is a power flow of 93W towards the load, only 70W of which is accepted and 23W is returned. One correction. The Bird wattmeter is installed at a point on the transmission line and it measures the power at that point. What is traveling is the energy. Power is the number of joules per second passing a fixed point. "Power flow" is somewhat of a misnomer. Sorry, you're right about "power flow". What I meant was a forward travelling wave carrying 93W towards the load. The other school of thought is that that's not true. The meter may *read* more "forward power" than is actually being delivered to the load, but that is a false indication because the instrument is not being used in the situation for which the power scale was calibrated. It certainly is being used in the situation for which it was calibrated if the Z0 of the transmission line is 50 ohms. I'm not sure which "transmission line" you meant here, but I don't think it matters anyway. The inserts are individually calibrated with a 50 ohm load impedance connected to the "Antenna" socket. The internal pot is adjusted to give the correct power reading (at one point on a meter scale that is pre-printed), and then the insert is reversed and a tab is bent to adjust the capacitive coupling to give the lowest possible reading. There may be some interaction requiring the two adjustments to be repeated, I don't know. If you meant the transmission line outside of the instrument, the calibration load may or may not include a length of matched 50 ohm transmission line - it doesn't matter. Inside the instrument, the characteristic impedance of the internal line is 50 ohms in order to avoid introducing an impedance bump into a system that is already matched, but even with say a 57 ohm internal line, the Bird insert could be set up to indicate power correctly into a 50 ohm load. The only difference is that the performance would become frequency-sensitive. On the other hand, we have yet to see an explanation in equivalent physical detail that is based entirely and exclusively on the viewpoint of travelling waves of power ... Please give up on your misconception. Those are traveling waves of *ENERGY*. Power is what is measured when traveling energy passes a fixed point. Perhaps that is your whole point of confusion. You're right, they would indeed be travelling waves of energy rather than power. But otherwise the same challenge is still out the if forward and reflected travelling waves of energy exist, we would expect to see a detailed explanation of how the Bird or any similar instrument interacts with such waves as distinct from the explanations that we already have for travelling waves of voltage and current. -- 73 from Ian GM3SEK 'In Practice' columnist for RadCom (RSGB) http://www.ifwtech.co.uk/g3sek |
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