The Quad Antenna: A Comprehensive Guide to the Construction, Design, and Performance of Quad Antennas

"In 1942 missionary station HCJB in Quito, Ecuador placed a new 10-KW 12-MHz transmitter in operation, feeding a four-element Yagi array. The combination of the 10,000 foot elevation, the low pressure associated with storms, and rain drops accumulating on the ends of the Yagi radiator produced spectacular fireworks. Carona discharge was common, and occasionally 4-foot long standing arcs were produced. The resulting heat would melt the end of the radiator, or even cause the aluminum to burn.... The material in this volume came from a study started when a change from a two element to a three element quad gave the expected forward gain increase, but at the expense of very poor front-to-back ratio." The author searches for the reasons.