The Lowly Quad for 17 meters.

In my experimentation you will see pages  relating to an antenna structural support which I think hs great utility on many types of antennas.  I call it the "T mount ".

It starts with a 8 foot long 4X4 cemented 2 feet in the ground.

Then the hardware is 1. A swivel base for your mast so one man can lean over a 2 inch mast
2. a support "U" that holds wood screws into the 4X4 to hold the mast about 5 feet from the ground. You actually use hex head 6 inch screws in predrilled holes . You tighten them with a socket wrench.

3. a boom attachment plate.(similar to any small beam attachment. )

If you will look on EBAY or other ham classified you will find "military Surplus" 4 foot long section of mast that sleeve together. (you can see the four foot sections in the picture above. They are cheap. I like the aluminum ones a bit better that the fiber glass although I do have some fiberglass sections to cut any interaction with the antenna.

you drill a 3/8 inch hole at the bottom of the base section of the mast. You use a long enough bolt to go through the base mount and the military mast so it will now rotate from on the ground to vertical.
You slip the base section in what ever swivel mount you design or buy and you put all your section together ( I like 28 feet total )and  you walk it up and pin it with your bracket at 5 feet.
It is now ready to guy.

I built mine first as a vertical so the U clamp that holds the mast at 5 feet was insulated. But for this adaptation insulation is not needed . Lowes and Home Depot has cyclone fense ware that makes a dandy attachment to the 4x4 to hold the mast.

Now you are ready to attach your simple boom plate at 28 feet . My boom is 8 feet, 1 1/2 inch thickwall fiberglass but you can dream up another boom with aluminum or even PVC with a dow rod support.(see above for boom shot)

Now the final touch is 4 direction guy lines made with weed eater line . You can tie off to anything-- Trees, the house ,the fence or some fancy guy supports to suit you.

Now What ?

The quad is best for a low location but how to get there? I first experimented with a two element wire parasitic beam fixed pointing east.( I can manually rotate it by moving the guy wires 90 degrees or 180 degrees) the mast section will turn one inside the other above the 4x4 .  To keep it static at the 7 foot separation for a 17 meter two element I used two 8 foot pvc spreaders at each end. Classic design was 1/2 wave dipole and 1/2 wavelength +5% reflector. Now we all know that you have to trim -- I did and the two element wire beam was great success. I worked tons of dx with 100 to 400 watts including the recent FT5ZM expedition to Amsterdam and St Paul Island. (twice-- cw and RTTY) . The antenna was inverted vee and the end 8 feet wide supports were swung  out by attaching a parallel line at each spreader and then attaching the pull line to the middle of that parallel line. This actually became two of my four guylines!!

Ok so that was fun but heck,if I added a half wave to hang down below the half wave above-- would that not be a quad? That is all I did. I move the feed point from the top to the bottom. On the reflector I used 1 12/ feet of ladder line to create a stub for tuning . This allows me to focus signal east or take the signal back side to the west . It is more of a diamond shape with the corners at the boom and near the ground . The bottom corner on the full wave loops is about 7 feet off the ground.for easy adjustment.
To keep the loops stable in the wind, I tie the corners to two heavy objects that I can move around --i.e. cinder blocks or bricks.

SWR is 1:1 to 1. I can tell that subjectively it is far better that the two element wire beam . I don't need the linear into Europe very much ( depending on propagation).  My reverse beacon reports are great. If you call cq on reverse beacons all these computer controlled receivers all over the word report hearing you and measures your signal in DB. Most signals reported are under 25 DB. (it also gives the receiving station's call and your code speed) . Any way the 17 meter low quad was excellent on the beacon.
 Always test your antenna with 100 watts on the beacon. Note WZ7I is in PA.  This test was May 24 2014 at 3:00 on 17 meter cw. This baby rocks.

You can use the same concepts with a tower in place. This concept has great potential on 80 meters with two towers or even 1 tower if  you can fly a 30 foot boom.
There it is the lowly Quad on a T mount.

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