A nonscientific and fortuitous observation . . . with a result that came as no surprise:
A week ago I carefully set up a Buddipole configured as a middling compromise between a vertical dipole and a vertical with one above ground counterpoise wire radial in a lazy L. Some fiddling got it right on resonance at 14.050, with an SWR of less than 1.2 to 1 across 25 Khz of the band, more or less. Using the longer whips and additional arms, it needed no loading coils. The plan was to have it ready for the NAQP. Then, the night before the contest, it snowed. About two inches accumulated on a garage roof some eight feet away from the feed point. It took a reduction of more than a foot of length on just the vertical element to get the antenna -- or maybe it was the garage roof itself -- back to near resonance. And at that the best SWR I could get with a 1 to 1 balun was about 3 to 1, almost flat across more than 60 Khz. I have no idea what the field strength difference was; but it seems clear that given ordinary environmental variations trying to dimension a perfec tly balanced radiator in free space canonical for every antenna design is an elusive idea. Even in Denver, where the weather is always exactly what we deserve. Ted, KN1CBR ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
