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#1
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Dave wrote:
no, only that you ignored the body of the message and answered what you wanted to discuss instead of what was asked. Yes, I did. I didn't know anything about the original question so I kindly offered to discuss something I know something about. If that is against netnews guidelines, could you show me where it says so? nope, that is a real world situation, but not the one under discussion. A 1/4WL matching section is not a "real world situation"? Since when? Everything I post is a real-world situation except for the obvious, e.g. one-second long lossless transmission lines. so which is it, in phase or 180 degrees out of phase??? It depends upon which signal we are talking about and whether the impedance discontinuity steps-up or steps-down. Assuming the generated forward wave (a1) has the voltage and current in phase at zero degrees: For a step-up impedance discontinuity, the s11(a1) reflection term will have the voltage at zero degrees (and the current at 180 degrees). For a Z0-match, b1 will be zero so s12(a2) must be equal magnitude and opposite phase to s11(a1). That puts the reflection from the load with voltage at 180 degrees (and current at zero degrees). All interference at port1 is totally destructive for a Z0-match. The s21(a1) term has voltage at zero degrees (and current at zero degrees). All interference at port2 is constructive so s22(a2) also has the voltage at zero degrees (and current at zero degrees). For a step-down impedance discontinuity associated with a Z0-match, the phases of the reflected voltages and currents are shifted by 180 degrees and b1 still equals zero. The above is exactly what happens at the match point at the input of a tuner. ***Therefore, the great majority of ham radio antenna systems have the voltages and currents either in-phase or 180 degrees out of phase at the tuner match point.*** In fact, all a tuner does is shift the magnitude and phase of the reflected waves from a mismatched antenna to be equal in magnitude and 180 degrees out of phase with the reflections from the match point. Therefore, all reflections are canceled at the match point but not between the match point and the antenna. This was all explained 64 years ago (when I was two years old) by J. C. Slater in _Microwave_Transmission_. Why do I have to explain it all over again? -- 73, Cecil http://www.qsl.net/w5dxp -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- |
#2
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On Mon, 24 May 2004 12:49:39 -0500, Cecil Moore
wrote: I didn't know anything about the original question Stock answer. This was all explained 64 years ago (when I was two years old) by J. C. Slater in _Microwave_Transmission_. Why do I have to explain it all over again? Possibly because you so ill understood it then as now? |
#3
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Richard Clark wrote:
wrote: This was all explained 64 years ago (when I was two years old) by J. C. Slater in _Microwave_Transmission_. Why do I have to explain it all over again? Possibly because you so ill understood it then as now? Well Richard, here's your chance. Please enlighten us on J.C. Slater's meaning of: "The method of eliminating reflections is based on the interference between waves. ... The fundamental principle behind the elimination of reflections is then to have each reflected wave canceled by another wave of equal amplitude and opposite phase." -- 73, Cecil http://www.qsl.net/w5dxp -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- |
#4
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On Mon, 24 May 2004 13:19:41 -0500, Cecil Moore
wrote: Well Richard, here's your chance. Please enlighten us on J.C. What was the original question? [accredited stock response] |
#5
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Richard Clark wrote:
wrote: Well Richard, here's your chance. Please enlighten us on J.C. What was the original question? [accredited stock response] When totally ignorant, divert the issue as long as possible. Why am I not surprised? -- 73, Cecil http://www.qsl.net/w5dxp -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- |
#6
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On Mon, 24 May 2004 14:06:28 -0500, Cecil Moore
wrote: What was the original question? [accredited stock response] When totally ignorant, divert the issue as long as possible. Why am I not surprised? Are you sure this is the original question? [accredited stock response] |
#7
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Richard Clark wrote:
Are you sure this is the original question? I am sure that our solar system and homo sapiens didn't exist when the original question was asked. -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- |
#8
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Richard Clark wrote:
On Mon, 24 May 2004 14:06:28 -0500, Cecil Moore wrote: What was the original question? [accredited stock response] When totally ignorant, divert the issue as long as possible. Why am I not surprised? Are you sure this is the original question? [accredited stock response] Richard Your earlier comment on things was quite accurate. This thread is hilarious! tom K0TAR |
#9
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![]() "Richard Clark" wrote in message ... On Mon, 24 May 2004 13:19:41 -0500, Cecil Moore wrote: Well Richard, here's your chance. Please enlighten us on J.C. What was the original question? [accredited stock response] It's clear that R.C. loves tweeking Cecil. Steve |
#10
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Steve Nosko wrote:
"Richard Clark" wrote: wrote: Well Richard, here's your chance. Please enlighten us on J.C. Slater's words in _Microwave_Transmission_. What was the original question? [accredited stock response] It's clear that R.C. loves tweeking Cecil. Trouble is, I usually have no idea what his random ramblings are all about. -- 73, Cecil http://www.qsl.net/w5dxp -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- |
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