Antenna de jour is a 40 meter 2 element, reversable,wire beam at 40 ft. high . The Christman method of 84 degree feedlines with a 71 degree phase was employed in a horizontal two dipole wire design spaced at 1/4wl. http://www.youtube.com/watch?v=7fWt_sigsZ4 Short Video Demonstration.
After watching this thing on youtube, I must apoligize for lousy video, looked much better on my computer, but hopefully the point was made, that a $50 wire antenna at 40 ft., using reversable phased double dipoles in two trees can compete as well as a mono band at 80 ft., I see that everyday, like today when a NJ station with stacked stepper monobanders at 85 feet got my same report, 5-9 into Saudia Arabia on 40 at 5pm in NY. $50 vs $10,000, made my day ! The ability to double my ERP on transmit and receive is priceless. Always get at least 25 dB front to back, The concept is extremely valid ,the thought came from exploring everything that I have learned from phased verticals and then applying that knowledge to horizontal dipoles, which was a leap in faith, and so far it's the best 40 and 80 meter beam I have used.You won't see this design in any antenna book as far as I know, hi. The concept is valid for ANY monoband frequency! Give it a try in your backyard, probaly work as well in an inverted vee configuration.
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ UPDATE; I have now completed an 80 meter version of same antenna, Pile up buster also and receiving 15 db consistant front to back from DX stations.
9.08dBI Gain 25DB front to Back Reversable 31degree TOA 46.5 Beamwidth 1.3 to one
40 ft. high
THE RELAY PICTURED IN UPPER RIGHT ,expandable, IS THE SAME FOR THIS ANTENNA, WAS VERTICALS, NOW DIPOLES !
Enjoy talking to the UK and many others usually around 7.160 or 3.787evenings, fun group very welcoming for DX contacts and antenna talk .Also on the OMISS Nets most evenings at 7.185 around 0100.and www.eham.net articles under my call in articles section.Take care and look foward to hooking up with you on the air. This antenna working better than many previous concepts pictured below.
Couple of winters ago backyard, guess what they say about quads in the Winter is true.
4 square did a credible job, but raised radials were a hazard to low flying birds and trespassers!
Shrunked 40 meter phased reversable quad, worked great but never survive upstate NY winter.
Better mention my primary antenna, impossible to photograph, is a 40 meter ladderline fed EDZ around 185 ft. long at 65 ft. Extremely versatile on all bands but very narrow beamwidth on 40, but nice to have 3dbd gain in two directions.
email; bobr1919@gmail.com Please check out my articles on www.eham.net Will be looking for you on the DX summit. Bob Last modified: 2012-12-19 20:56:13, 8932 bytes cached
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