Extended Double Zepp a new look

The only wire dipole with gain is the Extended Double Zepp ("EDZ"). It has 3db gain or doubles your power. I studied the possibilities on the internet. I wondered if I could do it in a inverted vee since I only had one 40 foot mast available . So I set out to test this puppy.
Turns out this antenna has 5/8 wavelength on each side of the center insulator. It is then fed with a combination of 450 ohm twin lead and 50 ohm coax to the rig. You must use a 4:1 current balun at the joinder of the coax to the section of 450 ohm twin lead.  The conventional teaching on the length of twin lead is dead wrong. You will see all these formulas for the lengths of these enormously long sections of 450 OHM ladder line. They may work but I don't believe the ladder line is radiating-- The 5/8 radiators are radiating on each side of the feed point just like any dipole. Does your feed line radiate on your dipole? I hope not.


I only had about 10 feet of Ladder line anyway so let's try that!! I built mine for 30 meters . With trimming to resonance it turned out to be about 70 feet (note that is pretty far off maybe because of the shorter ladder line but keep trimming and adjusting based on that good 'ol MFJ) on each half of the dipole section. The ladder line did its matching job with the balun and the EDZ on 30  was a GUN ! I elevated each end using the fiber glass spreaders lashed to tee posts and raising the ends to about 11 feet. I use pulleys at the top on the end supports to raise them up and down for quick adjustments. I use a pulley system on the 40 foot center mast.
The results were astonishing. Best wire antenna I ever made and definite gain as advertised. !! Weak Dx came back in one call in small pileups. What a success!! Let me tell you what a success it was. When FT5ZM (Amsterdam Island in the Indian ocean)  came up on 30 meters on the 27th of January 2014 , the pile up was expansive. REALLY!!! At 02:26Z I qsoed  after two (2) calls with 200 watts. Now you and I both know the luck involved to go 12,269 miles in a raging pile up in two calls-- But I'm just saying, I got there. 

But what about 17 meters? While 17 would load on the 30 meter EDZ for some reason-- It had no gain. I wanted this gain on 17!!! ONE ONE FEED SYSTEM!!  so I cut the dipole radiators at 5/8 wave on each side and soldered to the center insulator point .The 450 ohm ladder line now fed both the EDZs!  (and of course the single 50 ohm coax )  . Well, what do you know? The 17 meter EDZ worked great!! ( you have to trim to resonance) I tied its end to different tie off points to avoid interaction. but I love the gain and simplicity of the EDZ . I have phased verticals on 40 for DX but this EDZ antenna has great potential  on 40. Give it a try. Be sure and use a 4:1 Current Balun. I had to buy one but boy does it work.


Let me know how you come out and feel free to email me at mikew5zo@clear.net if you need a sounding board.




Here you can see the two dipoles are attached to the 15 feet of ladder line at the top of the mast

Here is the current balun at the bottom of the ladder line on the two band edz
 Between you and me ,I go back to my work on the "fan Vertical "and apply "W5ZO's Law", that if the feed point impedance is 50 to 75 ohms, and the rf can find a resonant radiator (or proper multiple of one), it doesn't matter how many radiators you have on the antenna , all of the rf goes to that resonator.(actually a hypothesis) .
At Christmas we went to Ruidoso New Mexico and I pre built  a 20 meter EDZ (only 7 feet of 450 ohm ladder line.)  . We had large pine trees on the property so I used a sling shot and got a good shot of fishing line through the tree at about 32 feet.( I tie the fishing line to a 3/4 inch nut to act as the projectile)  I hiked up the center of the zepp with weed eater line that I pulled through with the fishing line and tied off the lines inverted vee  using weed eater line as usual as a wonderful insulator. The swr worked like it did at home when I built it. 1.1 @ 14.020. I used 80 feet of 70 ohm RG6 to the balun. (look at the loss on that stuff!! beats LMR!!)
The first thing I learned was the while resonant on 20 ,I was able to use an internal tuner (icom 756p3) and put out a heck of a signal on 15/12/10 meters. Not so good on 17. 
Qrz.com has a great on line log !! log in and press the logbook button. It isn't bad as a full duty log although I'm an HRD guy. I made about 50 qsos in 10 countries in 3 days .The 20 meter EDZ was a blazing success. Reports were as good as expected in a mountain valley.Many 599s. (real) .
These EDZs are worth your effort. Where else do you get 3 db gain with a dipole? Good luck. Email me for suggestions.