Dr. Megacycle has it on the head with the length: 22 feet is 5/8 wave on 10 meters.
Good "commercial" automatic tuners will feed such an antenna all the way down below 80 meters. The SGC-230 is commonly used on ships feeding a 23 foot whip all the way down to the emergency SSB frequency at 2182 kHz. Many published tests have shown that getting the radials away from the ground is *very* beneficial and may well outweigh the loss of efficiency in reducing the height of the vertical. Back in '87, A. M. Christman, KB8I, published the results of studies he conducted in the Proceedings of the Third Annual Review of Progress in Applied Computational Electromagnetics for the U.S. Naval Postgraduate School, which he later summarized for hams in an article in the Aug 1988 issue of QST. That article is available to ARRL members on their web site. It gives numerous examples of the improvements to be expected as various counterpoise systems are used above ground. Let me point out to anyone interested enough to read my previous post that I misspoke. It was kindly brought to my attention by Arnie, PA3A, who observed I said a half wave radiator has a high radiation resistance when I meant to say it had a high feed point impedance. My conclusion was correct as to the benefit of a high feed point impedance, but there's a huge difference between the resistive value of the feed point impedance and radiation resistance! Ron AC7AC ______________________________________________________________ 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
