Author :
Hachten, Jack E. ; Ansley, Bud ; Bathker, Dan A.
Abstract :
A giant HF divided-boom Yagi antenna designed, constructed, and demonstrated by radio amateurs is described. The antenna, designed using the method-of-moments MININEC wire code, consists of 13 widely-spaced elements disposed on six towers, in a fixed-azimuth application. Overall antenna dimensions are 10 m by 100 m by 25 m above the ground: a structure roughly 0.5*5.0*1.0 wavelengths in the WARC-allocated 20-m amateur band. The elements are arranged for a considered balance among forward gain, sidelobe level, impedance level, bandwidth, and structural wind survival and construction economies, with an EM emphasis on forward gain. The antenna operates at a center frequency of 14.150 MHz ( lambda =21.15 m). The operating principle of the antenna is reviewed, and some of the errors to which it is prone are examined.<>
Keywords :
antenna arrays; 14.150 MHz; 20 m; 21.15 m; EM propagation; HF divided-boom Yagi antenna; MININEC wire code; amateur band; amateur radio; antenna dimensions; bandwidth; center frequency; construction economies; fixed-azimuth application; forward gain; impedance level; method-of-moments; sidelobe level; structural wind survival; towers; Bandwidth; Dielectric measurements; Electrical resistance measurement; Feeds; Impedance; Moment methods; Optical propagation; Poles and towers; Wire; Yagi-Uda antennas;