Low-power method of adjustment of medium-wave directional antennas

A new simple method of measuring the operating impedances and adjusting medium-wave directive arrays is presented. The desired current ratios and phases in radiating towers are set up by using conventional pentode amplifiers and wide-range phase shifters. The operating input impedances can measured by means of an operating impedance bridge, or by a voltmeter method which is described in more detail. Once the operating impedances are known, the dummy loads can be used in final matching of the high-power phasor system.