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On Mon, 21 Mar 2005 13:14:25 -0800, "John Smith"
wrote: Yet, it seems like such a design would suggest itself to many minds and be a good solution to many restricted spaces and, one does ponder why the math, methods, formulas, software, etc. has not been created to make such a matter of childs play--and well documented and explained. Hi John, In fact, nearly every "new" idea that hits this board can be found described with utter simplicity - years ago (10, 20, 40, 80 years). Very little math is demanded and the record is full of documentation. The continuous length of coil you describe has been anticipated by one in using a "slinky." The benefit there is that the springy form allows one to collapse or extend the coil to find resonance. Use two of them and you have a dipole. It performs, and has performed for years. You can buy one too. Why doesn't everyone use one? The reason goes back years ago to rather simple terms: size v. wavelength and the number and separation of nodes. It performs, but not as well as a larger antenna it attempts to replace. Hence: size v. wavelength is a restriction, there is only one node, and it has nothing (another separate node) to combine with. Once you can get your arms around these simple concepts, then you throw in loss - the numbers get ugly and the pain is real. We get tons of small antennas touted here. Many mobile whips seem centered around designs somewhat similiar to the one proposed. However, among the population of those many, when they are all compared the longstanding traditional designs win hands down. They win for very simple reasons. The list of rules, so to speak, is very short. Unfortunately there are too many simple reasons floating around as new and improved theory. The test of the newcomer is to separate those improved theories (noted for their baroque language, elaborate math and lack of field work) from ages-old results nailed down in rather ordinary terms. The new-and-improved theories call upon - separating the E and M fields; - unique properties of fractal math; - improved length efficiency; - proofs of polygonal analysis; - super gain; - over/tight/critical coupling; - faster than light transmission.... As you can see, the field of simple reasons abound. Some reasons have their attractive features, but once you try to pull the conversation into the realm of implementation, barriers to discussion bloom like weeds. 73's Richard Clark, KB7QHC |
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