Wednesday, May 27, 2015

Simple Ham Radio Antennas--Vertical Antenna for DX. Post #445.


If you have trouble viewing this video, please enter this URL into your browser: http://youtu.be/aOizaRd3Qtk. Another excellent antenna tutorial by Stan Gibilisco (W1GV). This time, Stan discusses the theory, construction, and use of a 40 meter vertical antenna for DX. Vertical antennas perform well if they are used in conjunction with a good ground radial system. The radial system supplies the missing half of the vertical element. With a decent radial system, this vertical directs most of its radiation toward the horizon. If you cut the vertical and radial wire lengths for a frequency in the lower portion of the 40 meter band (below 7.100 MHz), the antenna will work very well in the SSB portion of 15 meters as a 3/4 length antenna. This assumes you are feeding the antenna with 50 ohm coaxial cable. If you want multiband use between 40 and 10 meters, feed the antenna with ladder line or tv twinlead. The balanced feeders would then go into a balanced tuner and then on to your transceiver. You could also feed the balanced feeders into a 4:1 balun and then attach the balun to your tuner with a short length of 50 ohm coaxial cable. My current 40 meter vertical is built on the idea advanced by Stan Gibilisco. My ground radial system consists of 16 quarter wavelength radials attached to one leg of some 450 ohm ladder line, with the other leg of the ladder line connected to the vertical element. For now, this antenna serves me well as a general HF antenna. For the latest Amateur Radio news and events, please check out the blog sidebars. These news feeds are updated daily. You can follow our blog community with a free e-mail subscription or by tapping into the blog RSS feed. Thanks for joining us today! Aloha es 73 de Russ (KH6JRM).