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Thanks, the ones was considering are the yagis with the elements bent
into loops, but, from what I see, wouldn't really make a differnece. note some of the 1296 antennas shaped like that, at any rate! But, again, when I think-- dangerous things tend to happen! Never have done it- tho WA7TDU lived about 4 blocks from me when in K.Falls, and K7XC, down here in Reno also has done it. Keep thinking of giveing it a try, but dont knowif ever will happen. Jim NN7K Wes Stewart wrote: On Tue, 05 Apr 2005 15:33:42 GMT, Jim - NN7K wrote: |Thanks, Wes-- when originally considered it was looking at the moon |in terms of approaching a point source (the surface of the moon |being relatively small TIME-WISE- but the surface to the edges |being relatvly HUGE in distance , per Wavelength would allow a |distortion of a reflection. As I said , its dangerous to get me |thinking too hard (I tend to fall asleep)! Tho, hadn't considered |the (Cheezy) effect! makes me wonder if linear circular would be |the way to go, or would it distort as bad as other signals |(do to Faraday Rotation- the skewing of the signal's polarization)? |Just curious. The linear circular refers to circular yagi construction |rather than as a Helix? Or is this tilting at windmills? Jim - NN7K Linear circular is an oxymoron. When you phase two crossed Yagis to generate circular polarization, it is just as "circular" as a helix. It's been 20 years (how time flies) since I was operating EME but I remain interested. There is a current school of thought that switchable polarization has an operational advantage. I remain unconvinced when the complexity and degradation of performance is factored in. I don't know of anyone who is using true circular polarization (at VHF) even though their antennas are capable of generating it. The reason to have switching capability is speed up the QSO. With fixed linear polarization, at any given time, there can be spatial and Faraday rotation caused polarization mismatch between two stations located on different parts of the Earth. Switching polarization at one end can overcome all or part of this mismatch. Usually, if one waits long enough the always changing Faraday rotation will bring the mismatch to zero or near zero without any switching. So there is a trade of complexity for speed. In the modeling I've done, I have yet to see a case of high gain, crossed-element Yagis that were not degraded by the presence of the stacking hardware. |
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