![]() ![]() This area is located 12 miles from the Pacific Ocean and is subject to considerable day-to-day variations of temperature and humidity. It is between-and about one block from-the arms of a Y formed by a 30-yearold, 6.9-kV ac San Diego Gas and Electric distribution system that has had its voltage increased without benefit of insulator upgrade, its load increased by changing to higher power-handling transformers without benefit of increased wire size, and its maintenance service decreased as the power company strives to reduce cost: a typical suburban area suffering from gradual hardware degradation that leads to line-noise generation. The Square is an ideal antenna for hams living on small lots located near power lines that generate noise heard on the 40, 80 and 160-meter bands. The antennas can be easily mounted on towers using horizontally positioned poles (such as quad antenna spreader poles (2)), or installed on posts as phased arrays to get directivity in a small area. After using a 21-foot Square on 160 meters, Brian and I are confident that small Squares can be made for each band and perform well. The higher the Square, the greater its output level. Here, I'll share the performance, operational and construction information 1 gained as Brian progressed to final design.Īlthough I had to shorten the sides of the antenna to 21 feet to fit my available real estate, the results achieved at my location in omnidirectional signal reception and power-line-noise cancellation with such a simple 10-foot-high antenna are remarkable! This deviation illustrates the fact that you can make substantial dimensional changes without performance degradation provided symmetry is maintained and the resulting feedpoint impedance is matched to the feed line. While Brian explored antenna design trade-offs with his computer software program, with his guidance, I built several prototype antennas. ![]() Brian's article includes the description of a 25-foot-square receiving antenna and matching section along with some observed operational characteristics. In his accompanying QSTarticle, (1) Brian Beezley, K6STI, brings to our attention the details of how an antenna can be designed to eliminate (or greatly reduce) power-line noise to aid low-band reception. Here's how you can make a low-cost, low-noise, 21-foot-square receiving antenna that's certain to boost your DXability. ![]() Home - Techniek - Electronica - Radiotechniek - Radio amateur bladen - QST - A K6STI low-noise receiving antenna for 80 and 160 meters ![]()
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