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#1
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Yuri Blanarovich wrote:
There is too much reliance now going on modeling program results, ignoring some realities. Yuri, here is a modeling result that you might like. :-) I took a 102' dipole and loaded it in the center of each leg with an inductive stub that made the dipole resonant on 3.76 MHz. I added a one ohm series 'load' to each side of the stub. Drawing one leg of the dipole, it looks like this: ----------R2-+ +-R1----------FP--- ... other half | | | | inductive | | stub +-+ EZNEC reports 0.85 amps through R1 and 0.57 amps through R2, a difference of 33%. If one could model the inductive loading reactance as an actual physical coil instead of a lumped single point impedance, results would be similar to the above. Now here is something that might blow some minds. The inductive stub above is ten feet long. That's about 1/8WL on 20m. A 1/8WL shorted stub equals +jZ0. The results of running the above antenna on 20m is that the current through R1 is 185 degrees out of phase with the current through R2. At the time when the current through R2 is flowing toward the end of the antenna, the current through R1 is flowing toward the feedpoint. Wonder what Kirchhoff would say about that. If you replace the stub with a coil of the same reactance, not much changes. Tell W8JI to stop using lumped circuit analysis when he should be using distributed circuit analysis. :-) -- 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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Cecil wrote,
Tell W8JI to stop using lumped circuit analysis when he should be using distributed circuit analysis. :-) -- 73, Cecil http://www.qsl.net/w5dxp You know, it's against the law to kill people, Cecil. I almost choked to death on my morning cup of Bo Lee when I read that. :-) 73, Tom Donaly, KA6RUH |
#3
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Tdonaly wrote:
Cecil wrote, Tell W8JI to stop using lumped circuit analysis when he should be using distributed circuit analysis. :-) You know, it's against the law to kill people, Cecil. I almost choked to death on my morning cup of Bo Lee when I read that. :-) I apologize for that, Tom. If you had choked to death, would there have been enough evidence to convict me? :-) -- 73, Cecil, W5DXP |
#4
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Cecil wrote,
I apologize for that, Tom. If you had choked to death, would there have been enough evidence to convict me? :-) -- 73, Cecil, W5DXP Not in California, Cecil. It would have been the perfect crime. 73, Tom Donaly, KA6RUH |
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