2 meter half square antenna The half square antenna is easy to make and performs very well. After talking with Jimmy N9VXQ I made one as an experiment. Following are my construction notes. The formula I used comes out of the ARRL handbook. It is 984 x .95 (velocity factor) / freq. in mhz = antenna length in feet. The one (1) wave length dim. I used is 76.5". This makes the antenna resonant at 146.666 mhz which very close to where I wanted it, 146.000. But using this dim. makes all lengths easy to cut. 1/4 wave length = 19.125", 1/2 wave length = 38.25". I constructed my antenna from an old piece of RG58, 16ga. insulated wire, and some 1/2" by 1/2" pine wood for a frame. First start with wire longer than you need, 1/2" longer is enough. Make a frame and cut a piece about 19.375" and remove about 1/4" of the insulation. This piece is the first leg. Next tape this piece to the wood frame starting at the left end with the cleaned wire to the top. Next on the longer wire remove 1/4" of the insulation. Measure on the wood frame down from the upper left end of the wood frame 38.25" and mark the wood. Now lay the longer wire on the wood frame starting at the left about 1/2" away from the vertical wire. Tape both wires to the frame. At the make on the wood bend the wire parallel the vertical leg at the left and tape it. Put a pl259 connector on one end of the coax and remove the insulation about 1" on the other end. Unweave the brad and twist together. Remove all but 1/4" insulation from the center conductor. Tin all wires. Solder the center conductor to longer wire and solder the brad to the first vertical. Tape the coax to the frame and extend it out so that when it hangs down it at least 13" away from the vertical wire. This illustration is reverse of how Steve KB9RPS states it in his construction notes. It shows you a diagram of the antenna. 1/2 wave -------------------------------0 feed point for center conductor | 0 feed point for sheild | | | 1/4 | 1/4 | wave | wave | | | | | | | | The above antenna had 1.1 to 1.4 swr. I tested the antenna indoors hung 4" below the ceiling with an HT at 3/4 watt output. Moving the antenna around in the room caused the swr to vary. I tested the swr 146.000. Also, this set up was used on the air at 146.500 2/16/02 during our local net. The antenna received favorable reports. I was able to access two remote repeaters, one in Frankfort, IN. and one in Indianapolis, IN. If you have any questions or comments. Please email me at kb9rps@yahoo.com, Thanks! Have fun and enjoy, 73 KB9RPS, Steve