Just speculating -- I bet a half-wavelength wire in inverted-L configuration fed at the base with a parallel-tuned circuit would work well. The high-current part of the vertical piece would be at the top, there would be plenty of current in the horizontal part too, and very little local ground current.
On 8/24/2011 6:54 AM, William Ravenel wrote: > Steve Yates, AA5TB, has a very informative web page on EFHW antennas and how > to build a > parallel tuned circuit with a link coupled feed at the radio end to reduce > the 1800 to > 5000 ohm impedance to a 50 ohm non-reactive load. He has examples of both QRP > and QRO > versions of the circuit. I built the QRP version which uses a polyvaricon > capacitor > (available through Hendrix Kits among other sources) to create a very small > tuning > device that will match resonant End Fed half wavelength antennas on 40m, 30m, > 20m, and > 17m. I use it mostly with a 33 foot wire on 20m raised on a 31 foot Jackite > fiberglass > pole and have had fun working DX with 5 watts. It is easy to change bands by > exchanging > the wire with one cut for the band of interest. I do not use a counterpoise > and do not > have any trouble at the rig. Steve explains why this works. For higher power > a one > meter counterpoise helps. I use this antenna with a K1 and K2, both with > internal > antenna tuners. The tuners are not needed, but I leave them activated to > easily > compensate for any small mismatch across the band. > > Steve's page is found at http://aa5tb.com/efha.html > > William Ravenel, AI4VE > ______________________________________________________________ -- Vic, K2VCO Fresno CA http://www.qsl.net/k2vco/ ______________________________________________________________ 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
