Abridgment of vacuum tube synchronizing equipment

Potential from high-voltage circuits is obtained by means of capacitance transformers. This potential is applied to the grid circuit of vacuum tube amplifiers the output from which drives a rotating type of synchroscope. Thus the vacuum tube synchronizing equipment makes unnecessary costly high-voltage transformers which have been almost universally used for synchronizing in the past. The paper describes the commercial apparatus, gives equations pertaining to the vacuum tube amplifier and shows calculated and measured characteristic curves.