Development of Directive Transmitting Antennas by R.C.A Communications, Inc.

Progressive stages in the development of short-wave directive antennas for long-distance communication are outlined. The scope of development described embraces the period from 1923, beginning with experiments on a transmitting wave antenna at Belfast, Maine, to the present commercial directive antennas used in the world-wide short-wave system of R.C.A. Communications, Inc. Various types of directive antennas are theoretically analyzed and their performances under practical conditions studied. The effects of seasonal variations, heights above ground and polarization are considered. The radiation properties of simple wires and the radiation patterns of various combinations of wires are described in detail. The economic aspects of these directive antennas as exemplified by the standard antenna models A, B, C, and D are developed.