Six Meter Antenna Projects by N2KBK
Compliments of N2KBK!
Here you will find 2 simple antenna projects for 6 meter fun designed for easy and inexpensive construction.
The first project is a 3 element 6 meter beam.
The second project below is the 6 meter Halo antenna.
A 3 ELEMENT BEAM
Director————-106 and 1/2 inches
Spacing between elements is 34 and 1/2 inches. The elements are 1/2 inch aluminum tubing of 1/16-inch wall thickness. (you can cut up an old TV antenna, they work great).
The Boom length is 72 inches (6 feet). The boom is 1 and 1/4 inch tubing.
Gamma Match Construction
To attach the gamma rod to the antenna you will need to mount an SO-239 chassis connector to the center of the driven element. This can be made from a piece of sheet metal about 1 inch wide by 3 inches long. (See drawing below) Bend the long side of the sheet metal into and L-shape so that you now have a 2×1 inch surface and a 1×1 inch on a 90 degree angle. Then center punch the 2×1 side and mount the SO-239 connector in the middle. Next bend the 1×1 inch surface onto the center of the driven element and secure it with 2 sheet metal screws.
GAMMA MOUNT BRACKET ASSEMBLY
See drawing below for typical gamma match placement and construction.
Take this strip and bend it around the driven and over to the gamma. Make sure it folds back over so that you can drill 1 hole at each end. You can use your own construction methods and fabrication.
A GAMMA MATCH
The inner portion is cut from RG-8 coax after you remove the black ‘skin’ and the copper braid. You can attach 50 ohm coax to this antenna after you add a gamma match.
The 6 meter Halo is a good antenna that can be used for the car as well as the house.
This antenna maintains good omni-directional horizontal polarization.
Basically the antenna is a half wave dipole bent into a circle, BUT shorter than a dipole for this frequency. The circumference is 60-70 inches. By using the gamma match (see above) you can use regular coax. This is a high-Q antenna, so bandwidth is about 200khz. (Perfect for 50.100Mhz – 50.200Mhz where most of the 6m ssb activity is.)
The 2 large discs can be about 4-5 inches round and the small disc about 1.5 inches. Mount the 2 larger discs at the ends of the halo by screwing end caps to the center of them and then the end caps will go over the ends of the halo.
Next drill a small hole in one of the larger discs and the same size hole in the exact center of the small disc. Put a 2 inch bolt through the center and run a nut up the bolt to lock it in place. Then a nut on each side of the large disc to secure the bolt to the larger disc.
Mount the gamma rod the same as you did on the beam (see above), BUT bend the gamma to match the curve in the halo. Finally take three 2-3 inch nylon spacers and mount them between the large discs. You should drill 3 holes in a triangle patern and use 3 nylon bolts and nuts. This will ensure that the ends plates do not move around on you. You can mount this antenna on a mast by making some type of bracket for support.
(Just try to put the bracket by the mount where the coax/gamma is so that the mount should not affect the antenna preformance.)
To match the antenna simply move the gamma around a few times (move it in small increments is really tough). Once you get the S.W.R. down below 3:1 then move the small disc by loosening the nut and turning the small disc.
(AGAIN, move it in small increments)
Many thanks to the late Robert Cook, WB2OHP for the endless hours of advice, help and lots of radio checks.
He was the person who introduced me to “The Magic Band” – Thanks Bob.