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#1
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Roy Lewallen wrote:
Yes, I disagree with that. Then you disagree with Balanis. -- 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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I don't have Balanis. Can you provide a short quote where he states that
the current at the terminals of a two-terminal lumped component are unequal? Roy Lewallen, W7EL Cecil Moore wrote: Roy Lewallen wrote: Yes, I disagree with that. Then you disagree with Balanis. |
#3
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Roy Lewallen wrote:
I don't have Balanis. Can you provide a short quote where he states that the current at the terminals of a two-terminal lumped component are unequal? He doesn't use lumped components and probably for good reason. But here's the quote that allows my analysis. "Standing wave antennas, such as the dipole, can be analyzed as traveling wave antennas with waves propagating in opposite directions (forward and backward) and represented by traveling wave currents 'If' and 'Ib' in Figure 10.1(a)." This means that net total current equals If+Ib. The fact that the feedpoint current occurs at a current maximum point ties both ends down. 'If' must traverse 90 degrees and 'Ib' must traverse 90 degrees in addition to the 180 degree phase shift due to reflection from the open end. Besides the coil, an 8' whip gives about 22 degrees phase shift in a round trip. Adding the 180 degree phase shift due to the open end reflection gives 202 degrees. But we know the phase shift is actually 360 degrees. Where can the additional 158 degrees of phase shift come from except from the coil? Center-loaded mobile antennas are still an electrical 1/4 wavelength. If there's no phase shift through the coil, where's the missing 158 degrees of phase shift taking place? -- 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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So, in short, I don't disagree with Balanis.
Roy Lewallen, W7EL Cecil Moore wrote: Roy Lewallen wrote: I don't have Balanis. Can you provide a short quote where he states that the current at the terminals of a two-terminal lumped component are unequal? He doesn't use lumped components and probably for good reason. But here's the quote that allows my analysis. "Standing wave antennas, such as the dipole, can be analyzed as traveling wave antennas with waves propagating in opposite directions (forward and backward) and represented by traveling wave currents 'If' and 'Ib' in Figure 10.1(a)." This means that net total current equals If+Ib. The fact that the feedpoint current occurs at a current maximum point ties both ends down. 'If' must traverse 90 degrees and 'Ib' must traverse 90 degrees in addition to the 180 degree phase shift due to reflection from the open end. Besides the coil, an 8' whip gives about 22 degrees phase shift in a round trip. Adding the 180 degree phase shift due to the open end reflection gives 202 degrees. But we know the phase shift is actually 360 degrees. Where can the additional 158 degrees of phase shift come from except from the coil? Center-loaded mobile antennas are still an electrical 1/4 wavelength. If there's no phase shift through the coil, where's the missing 158 degrees of phase shift taking place? |
#5
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Cecil Moore wrote:
Roy Lewallen wrote: Cecil Moore wrote: Roy Lewallen wrote: Cecil Moore wrote: Roy Lewallen wrote: Cecil Moore wrote: Roy Lewallen wrote: Cecil Moore wrote: Roy Lewallen wrote: Cecil Moore wrote: Roy Lewallen wrote: Cecil Moore wrote: Roy Lewallen wrote: Cecil Moore wrote: Roy Lewallen wrote: Cecil Moore wrote: Roy Lewallen wrote: Cecil Moore wrote: Roy Lewallen wrote: Cecil Moore wrote: Roy Lewallen wrote: Cecil Moore wrote: Roy Lewallen wrote: |
#6
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David Robbins wrote:
Cecil Moore wrote: Roy Lewallen wrote: So what's the answer, Dave? Is there a current phase shift through a mobile antenna loading coil or not? Seems to me, if a coil can propagate the current phase in zero time, that is faster than light operation. -- 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! =----- |
#7
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I'm sorry. If I'm bothering the readers, I'll be glad to bow out.
My postings aren't really directed to Cecil -- I know much better than to imagine that I'll ever change his mind, and I'm a firm believer in not wasting time on things I can't change. No, you and the other readers are really the audience, and the whole reason for the postings. If you and the other readers would rather I shut up, I'll be more than happy to spend my time at more productive pursuits. Just let me know. Roy Lewallen, W7EL David Robbins wrote: Cecil Moore wrote: Roy Lewallen wrote: Cecil Moore wrote: Roy Lewallen wrote: Cecil Moore wrote: Roy Lewallen wrote: Cecil Moore wrote: Roy Lewallen wrote: Cecil Moore wrote: Roy Lewallen wrote: Cecil Moore wrote: Roy Lewallen wrote: Cecil Moore wrote: Roy Lewallen wrote: Cecil Moore wrote: Roy Lewallen wrote: Cecil Moore wrote: Roy Lewallen wrote: Cecil Moore wrote: Roy Lewallen wrote: Cecil Moore wrote: Roy Lewallen wrote: Cecil Moore wrote: Roy Lewallen wrote: |
#8
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On Mon, 03 Nov 2003 16:36:59 -0800, Roy Lewallen
wrote: I'm sorry. If I'm bothering the readers, I'll be glad to bow out. My postings aren't really directed to Cecil -- I know much better than to imagine that I'll ever change his mind, and I'm a firm believer in not wasting time on things I can't change. No, you and the other readers are really the audience, and the whole reason for the postings. If you and the other readers would rather I shut up, I'll be more than happy to spend my time at more productive pursuits. Just let me know. Roy Lewallen, W7EL Roy: You and a handfull others are on my "must read" list. Keep up the good work! Jack K8ZOA |
#9
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Roy and Cecil -- I find your posts most informative -- ignore the flack.
Keep up the good work -- valuable sources -- 73 From The Keyboard =============== "Roy Lewallen" wrote in message ... I'm sorry. If I'm bothering the readers, I'll be glad to bow out. My postings aren't really directed to Cecil -- I know much better than to imagine that I'll ever change his mind, and I'm a firm believer in not wasting time on things I can't change. No, you and the other readers are really the audience, and the whole reason for the postings. If you and the other readers would rather I shut up, I'll be more than happy to spend my time at more productive pursuits. Just let me know. Roy Lewallen, W7EL David Robbins wrote: Cecil Moore wrote: Roy Lewallen wrote: Cecil Moore wrote: Roy Lewallen wrote: Cecil Moore wrote: Roy Lewallen wrote: Cecil Moore wrote: Roy Lewallen wrote: Cecil Moore wrote: Roy Lewallen wrote: Cecil Moore wrote: Roy Lewallen wrote: Cecil Moore wrote: Roy Lewallen wrote: Cecil Moore wrote: Roy Lewallen wrote: Cecil Moore wrote: Roy Lewallen wrote: Cecil Moore wrote: Roy Lewallen wrote: Cecil Moore wrote: Roy Lewallen wrote: Cecil Moore wrote: Roy Lewallen wrote: |
#10
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David Robbins wrote:
Cecil Moore wrote: Roy Lewallen wrote: Aww Dave! Cecil, Dave and a few others here serve as both education and somethimes entertainment. Go with the flow, learn something and when you get tired stop reading the thread. It's all good, man! |
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