Tom, thats true if you have one radial, but making it 1/4 wavelength long minimizes RF on the rig and, in most situations, only a small part of the RF flows in it. Its a function of the ratio of the impedances of the "radial" and the radiator.
Consider the "ideal" case. A radiator close to 1/2 wavelength may present a feed point impedance of 2000 ohms while a carefully trimmed 1/4 wavelength radial may show something near 35 ohms. In that case, well over 95% of the RF power is delivered to the 2000 ohm impedance of the antenna and less than 5% is delivered to the radial. Real life is usually not that good. Most compact ATU's can't handle the very high impedances near 1/2 wavelength so the antenna must be longer or shorter than ideal, and the "radial" usually doesn't provide anything less than a few hundred ohms impedance. Even so, most of the RF is delivered to the radiator. 73, Ron AC7AC Just to restate the obvious: Do not make the radials resonant on any of the operating frequencies. Doing so causes high current in the radials and you end up with a very low horizontally polarized radiator. 73, Tom (K7ZZ) ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
