This antenna may not be practical for your qth but it is the best muti band antenna I have ever constructed. So I will pass it on.
This antenna works perfect on 20/40.17. It will atu on 60/30. It is my go to antenna just messing around. I refer you also to my work on the fan verticals. That will work very well with this antenna and in fact DOES.
If you have the room for it and two levels of guys ,Ill tell you my construction design, First, I use an 8 foot 4X4 post 18 inches in the ground with concrete. I use home brew scraps including aluminum military antenna support section ( 4' each to 24') at the bottom and old scrap aluminum tapered down to 1/2 inch all the way to the top. The radiator is attached to but insulated from the 4x4.and the ground. properly guyed ,this antenna is tough and stable. I use insulated brackets to attach it vertically. You can design your own, Just be sure they are insulated from the radiator. I built this antenna 100% from scap.
The base support must be insulated from the post and the ground. At the base, I use an insulated U clamp with a bolt through a hole drilled through the diameter of the bottom section, so it will pivot. That pivots so the antenna raises and swings up without moving from the base as I push it up. Mine goes up in one piece. If you need ideas on insulating the base. Email me.
Now, I use 72 ohm RG6. It is extremely low loss ( check out the loss chart, it is wild) It is highly recommended. I feed with 450 ohmn ladderline for 10 feet to a 4:1 current balun .
As I said , it needs guys at two levels. I use weed eater in spools . Great!! I tie off on trees, fence posts, the house , or Tee Post from Home Depot. Figure it out.
Then I attach ground radials to the ground side of the coax. I have about 30. They can be any length over 1/10 wave length but mine are about 20 to 70 feet long. ( insulated) ,. the number is dictated by you workable space. I recommend at least 10 ground radials. Again, they do NOT have to be any particular length.
As I said , this antenna is not for everyone. I love verticals. I have made them with wire in trees, roof mounted -- ground mounted -- They all are fun. Some say the " Radiate equally poorly in all directions" but I found DX joy with them for hundreds of band countries. I have two acres so space is no problem but as a multiband ,highly effective and efficient antenna , this 43 footer beats any non gain antenna I have ever used and that is a few.
This antenna works perfect on 20/40.17. It will atu on 60/30. It is my go to antenna just messing around. I refer you also to my work on the fan verticals. That will work very well with this antenna and in fact DOES.
If you have the room for it and two levels of guys ,Ill tell you my construction design, First, I use an 8 foot 4X4 post 18 inches in the ground with concrete. I use home brew scraps including aluminum military antenna support section ( 4' each to 24') at the bottom and old scrap aluminum tapered down to 1/2 inch all the way to the top. The radiator is attached to but insulated from the 4x4.and the ground. properly guyed ,this antenna is tough and stable. I use insulated brackets to attach it vertically. You can design your own, Just be sure they are insulated from the radiator. I built this antenna 100% from scap.
The base support must be insulated from the post and the ground. At the base, I use an insulated U clamp with a bolt through a hole drilled through the diameter of the bottom section, so it will pivot. That pivots so the antenna raises and swings up without moving from the base as I push it up. Mine goes up in one piece. If you need ideas on insulating the base. Email me.
Now, I use 72 ohm RG6. It is extremely low loss ( check out the loss chart, it is wild) It is highly recommended. I feed with 450 ohmn ladderline for 10 feet to a 4:1 current balun .
As I said , it needs guys at two levels. I use weed eater in spools . Great!! I tie off on trees, fence posts, the house , or Tee Post from Home Depot. Figure it out.
Then I attach ground radials to the ground side of the coax. I have about 30. They can be any length over 1/10 wave length but mine are about 20 to 70 feet long. ( insulated) ,. the number is dictated by you workable space. I recommend at least 10 ground radials. Again, they do NOT have to be any particular length.
As I said , this antenna is not for everyone. I love verticals. I have made them with wire in trees, roof mounted -- ground mounted -- They all are fun. Some say the " Radiate equally poorly in all directions" but I found DX joy with them for hundreds of band countries. I have two acres so space is no problem but as a multiband ,highly effective and efficient antenna , this 43 footer beats any non gain antenna I have ever used and that is a few.
NEWS FLASH!! I rebuilt a 33 feet of vertical structure with the last 10 feet on top of the 33 feet composed of wire in and inverted " L" and tied off horizontal to the ground , You can tie to another support or a tree . Use your imagination . It even works with a sloping angle back to the earth.
By doing the last 10 feet with wire in the inverted L I was able to drop to just one set of guy ropes!!
It works 40/20 /30 . You tune to resonance if necessary using 1 quarter wave counter poise elevated above the ground and attached to the base of the vertical resonator. It is my best go to 40 meter antenna. A couple of ideas emerged. The first was out of necessity. the top 10 feet of the big vertical was destroyed in the wind. So I made it an inverted L with wire sloping down at 45 degrees. Much easier to manage and it worked the same bands. Worked great. Now what I am about to tell you is revolutionary. Did you know that 2 elevated radials replace 120 pain in the ass ground radials? Yep. Check it out. I always wanted to try this. With my vertical still insulated from ground , I attacked the ground side of the coax to a wire and moved the Balun up 3 feet. Then I attached a 33 foot radial at 3 feet. and ran it parallel to the ground. I decoupled the ground radials completely. It showed me resonant at 9mhz. I added 8 feet to the elevated radial. It shows SWR 1:7 to one at 7.020 and bingo. I lit up 31 RBN station on 40 meters . It worked as well as all those damned ground radials. Call me Crazy. Can I have an AMEN??
73 and have fun with antennas W5ZO
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