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Is Cecil still beating that same old dead horse that only he rides?
Walter Maxwell wrote: On Sat, 12 Aug 2006 14:30:34 GMT, Cecil Moore wrote: Reg Edwards wrote: I agree, a coil at sufficiently high frequencies begins to behave something like a transmission line with a very low velocity factor. Just below its self-resonant frequency, it behaves somewhat like a transmission line of less than 90 degrees. snip But maybe one hoot. :-) My 75m bugcatcher coil is operated relatively close to its measured self-resonant frequency of 6.6 MHz. If I wound a bugcatcher coil to be self-resonant on 4 MHz and then used 2/3 of that coil for a loading coil on 4 MHz, its VF would not change and its electrical length would be 60 degrees accompanied by the appropriate 60 degree delay through the coil. Hi Cecil & Reg Sometime during the '70s I measured the self-resonant frequency of the 80m Hustler loading coil, 6MHz. The series resistance of that coil was 31 ohms at 4 MHz. That is why they claimed 'lower swr than with othe brands'. What a fraud. On the other hand, I also measured the Webster KW-80, self-resonant at 14.0 MHz, with a series resistance of 8 ohms at 4 MHz. I reported this on Page 6-12 in Reflections. So I ask you, Cecil, why would you want a bugcatcher self-resonant at 4 MHz for operation at 4.0 MHz, even if you used only 2/3 of it as a loading coil. Looking just to heat the coil instead of radiating the energy into space? Walt, W2DU |
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