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![]() "Cecil Moore" wrote in message ... Dale Parfitt wrote: I have repeatedly asked you to supply us with your original quote from W8JI's page concerning a straight radiator is the best. Quoting W8JI's web page: "How do we make a small antenna as efficient as possible?" "... we make the antenna as large and straight as possible in a line. We don't fold, bend, zigzag, or curve the antenna especially in the high current areas." I don't know what the fuss is all about. Transmission line currents don't radiate (much) because they are out of phase. Random folding of an antenna more often than not introduces transmission line currents into the antenna itself - not good for radiation purposes. Transmission line currents cause destructive interference - that's good for transferring power from one place to another but not good for radiating RF. There are certain special-case antennas where folding occurs without introducing destructive interference, e.g. a 1/2WL folded dipole or a full-wave quad where the wires are a large enough percentage of a wavelength apart so they don't cause near-field destructive interference. Hint: RF radiation cannot be understood without understanding constructive and destructive interference in the near, medium, and far fields. -- 73, Cecil, IEEE, OOTC, http://www.w5dxp.com Thank you Cecil, That's all I was looking for. Dale W4OP |
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