On Thu,12/29/2016 1:53 PM, Bill Frantz wrote:
If this is really what is going on, then a bit longer than 1/8 wave should be about right for radials on/under the ground.
I did an NEC study several years ago placing a half wave dipole at heights above ground from several feet down to an inch, and varied the length of the dipole so that it remained resonant at each height. From that I plotted VF. As close to the earth as I could model it, VF was about 0.7. At heights of 3 ft or more, VF on 160M was close to 1.
N6LF published a detailed study of radial lengths and recommended an optimum length for elevated radials slightly less than a quarter wave. His basis was that making them slightly shorter caused current distribution between them to be more equal, which reduces ground losses. Rudy's website is a wealth of great info about radials.
73, Jim K9YC ______________________________________________________________ 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 Message delivered to [email protected]
