Modulated-Beam Cathode-Ray Phase Meter

This paper describes a phase meter developed to measure the phase-shift characteristics of amplifiers used in vibration-measurement work. It employs a cathode-ray tube, in conjunction with a circuit establishing a circular time base on the screen of the tube, and a "clipper" circuit fed in turn by the two voltages, the phase difference of which it is desired to measure. The change in angular position of the semicircle obtained on the screen is the phase difference in the voltages. The method possesses several distinct advantages, including indication of the sense of the phase difference and accurate operation at subaudible frequencies.