J-type communication antenna production ----- J-Communications Antenna

Keywords: 29.6MHz horizontal half wave dipole antenna Homemade simple 29.6MHz horizontal half-wave dipole antenna I use one-half of the wavelength vertical network antenna in the ten-meter band. Since the signal from the Guangdong direction is particularly strong, the weak signal from other directions is covered, it is difficult to connect to other regional ham. So I want to make an antenna with directional. Of course, the eight-timber antenna is preferred. Since the volume of the eight-timber antenna is huge, the environment I live is difficult to install. Later I found that the radiation of the horizontal dipper antenna (as shown in Figure B) had certain directionality, I want to try the effect. Two-segment vibrators of the half-wave dipole antenna are about 245 cm, I chose the low-voltage wire transformed from the grid (calculation formula: 300,000 kilometers ÷ 29.6 × 0.5 × 0.96 = 4.86 meters), the aluminum core in the wire is thick and less than 10 Sparters. I first made the skeleton of the vibrator, using quarters of PVC tube (4 yuan for building materials market, 6 meters long), then use a 1 meter-long four iron pipe (as shown in Figure A-1), in the tube Electric drill punching is tightened with a bolt, and the two PVC pipes remains about 5 cm. Next, the two vibrators were pulled into the PVC tube, and the vibrator was more than 10 cm long, and it was used to regulate the standing wave. The 50 Euro coaxial cable is connected to the two vibrators, respectively (preferably solder welding), and then use the waterproof tape to stick the two joints (as shown in Figure A-2), which is fixed on the rod of the antenna. The antenna rod adopts a 1.5-inch steel pipe). In this way, the antenna is basically completed, hit a slightly coarse hole in a place from the top of the antenna rod, wearing 1 iron bars, 1 steel tube 10 cm, and pull three wire drawing. To the above (as shown in Figure A-3). My simple steering method is to embed a 1.8-inch steel pipe on the ground, insert the bottom end of the antenna rod to the inside, and it is best to put a circular or elliptical stone in the bubble on the ground to facilitate rotation, in a suitable height Putting, putting 1 iron bar that can be rotated (as shown in Figure B), the entire antenna is basically completed. Be I put the antenna from the ground, pick up the machine, try a standing wave, found that the standing wave around 29.6MHz is about 1.8, which may be due to the thicker of the vibrator. So I cut the vibrator each 5 cm, resident wave ratio 1.3; about 1.3 on 28MHz; cut about 5 cm, this time the 29.6MHz station wave ratio is 1.2. My feeling of this antenna is not very direction, the steering device is not flexible enough, but can meet the general requirements, the production is simple and practical, I am now using it, welcome us to see!