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![]() "Cecil Moore" wrote in message . net... Steve N. wrote: ...if you get my drift. Steve, I put "missing" in quotes because there is no missing part of the antenna. I think I understand your intent. What I say is drop the following sentence: "I've been saying for months that a 75m mobile antenna doesn't have to be 90 degrees long to be resonant. Forget electrical length discussions in regard to anything but a single transmission line piece. I don't think it makes any improvement in understanding what is going on to add talk about something you want to call the electrical length of a complex system of lines and components. I think it adds unnecessary complication. My opinion is that this is taking a concept used in transmission line discussions and applying it where it is not needed. Though I didn't verify your math on the original example, I don't find the type of result surprising and doing he math is all that is needed. I would not have expected that the "degrees" of electrical length to add up to 90, or whatever an equivalent antenna or t-line length would have been. I do understand the desire to form what I call a "mental model" which allows us to understand how things work so that we can use them. Lord knows that waves need some kind of help to get them into our minds so we can feel comfortable about how this all fits together. In fact, sometimes I get the impression these discussions become a battle between two mental models that may work for the individual posters, but don't fit into the other's model and many words ensue trying to pull each other over to the other's mental model paradigm. Talk such as the following it sufficient. (although I'd have to think about the specific thing you say here since I don't think about transmission line things in those terms) All that is required is that (Vfor+Vref) be in phase with (Ifor+Iref) where those are phasor additions. ...detail snipped -- 73, Cecil http://www.qsl.net/w5dxp Whatever lights your fire. It is fun reading some of the discussions, though 73, Steve, K9DCI |
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