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On Tue, 11 Nov 2003 10:31:35 -0600, Cecil Moore
wrote: Jack Smith wrote: (1) Input current = output current (2) No phase shift. If you model the circuit using the lumped values for the antenna R and jX components it's easy to see this. Anyone not believing this can try modeling the base inductor as: O----[0.3 ohms R']--[+j192 ohms]---[0.3 ohms R'']----0 Put current through it using your favorite SPICE simulator and compare the current through the R' and the R''. The two plots coincide. We know what the model says. The original argument was over whether a 75m bugcatcher coil, containing distributed resistance, inductance, and capacitance, actually possesses those same characteristics in reality. A statement by a ham over on eham.net triggered the argument: "If you look at HOW an inductor works, the current flowing in one terminal ALWAYS equals the current flowing out the other terminal. " That is how a lumped inductor works in a model. That is not how a distributed inductor works in reality. My understanding of the particular question being debated is that the loading coil is physically small and at the frequency in question may be safely treated as a lumped element, and that some have said that current-in current-out. The fact that the small coil is connected to an antenna which is not physically small is immaterial. I apologize if I've misunderstood where this topic is at; it's been very difficult to follow as it drifts back and forth. Jack |
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