Stan, that's not a true half wave radiator on most bands. They suggest a wire length of 20 or 30 feet, which will be efficient on 12 through 6 meters where it's at least 1/2 wavelength long, but on the lower frequency bands it's just a short random length wire with an auto-transformer to assist with impedance matching.
There's a huge difference between a full-size radiator and a short one that is made "resonant" using supplemental inductance. It will work as you, I, or anyone who has used a short, random length wire can attest, but it's efficiency is much lower than a radiator that is physically a half wavelength long. There's just nothing that can replace physical size for an efficient antenna. Not too much is lost on even multiples of a half wavelength. The impedance at a full wavelength, two wavelengths, etc., drops with each multiple, but still remains far above that impedance of even a 1/4 wave length radiator. And when dealing with any end-fed antenna worked against ground, higher impedance at the end of the antenna means higher efficiency for a given ground. 73, Ron AC7AC -----Original Message----- And for those with more money than brains (that would be me) you can purchase an end fed halfwave antenna from the Emergency Radio Club of Hawaii for $42. I bought one and it works great with the entire Elecraft family. Great to have a simple yet efficient portable antenna that fits into a sandwich baggie. This site also has the plans to build this one on your own if you would prefer. The main website is at: http://www.earchi.org/proj_homebrew.html The page for building it yourself is at: http://www.earchi.org/pdf/endfed.pdf And the page for the 'easy way out' is at: http://www.earchi.org/pdf/endfed20.pdf 73, Stan WB2LQF KX1 #2411 K1#2994 K2# 6980 K3#5244 K9 #1 (Cocoa the Chihuahua) Everything is QRP, even the dog. ______________________________________________________________ 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
