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Dave wrote:
Where is the other 74 degrees?? This is the question that started this 2 month discussion. Is there a fallacy in Corum's paper? Does Corum's paper apply to a combination of a loading coil and radiating elements? My reasoning is as follows: if I draw a phasor diagram, I have +10 degrees phase shift from the feed point to the base of the coil. I can then assume a +90 degree phase shift in the coil, classical inductive response; then, the 'stinger', from the top of the coil to the tip of the antenna produces a net -10 degree phase shift from both inductive[+] and capacitive[-] effects resulting in a net 90 degree phase shift for the full eight foot antenna. Am I being too simplistic? I conclude that I have a 16 degree long antenna with a feedpoint resistance of ~13 ohms [ Rr = ~1.0 ohm and Rloss = ~12 ohms] with zero ohms reactance [resonant]. [And that the phase shifts stated above are fundamentally correct.] You don't need to go to anywhere near that much trouble. If you replace the stinger with a lumped series RC to ground with the same impedance as the stinger, you'll get nearly the same currents, both magnitude and phase, at the top and bottom of the coil as you did with the stinger. No "missing degrees" -- no "degrees" at all, in fact. No forward and reverse traveling waves, no standing waves. No smoke and mirrors, no bafflegab. Just plain old circuit analysis. Roy Lewallen, W7EL |
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