Abstract: A unidirectional current with i-f variations superimposed thereon is applied to the interconnected emitters of a pair of transistors, the collectors of which are coupled to a succeeding stage by a narrow-band filter and by a wide-band filter respectively. The unidirectional current with i-f variations is amplified by a selected one of the transistors and filtered accordingly, depending upon which of two polarities of potential is applied between the bases of the transistors.

Abstract: A D-C converter obtains high voltage by peak-to-peak rectification of alternating potentials supplied at the secondary of a step-up transformer. The primary winding of the transformer is tuned with series capacitance and driven from the output circuit of a pulse amplifier providing pulses with a repetition rate equal to, or an integral submultiple of, the resonant frequency of the tuned transformer primary. The pulse amplifier is made to offer a low source-impedance so that the Q of the tuned primary is large enough that a substantially sinusoidal voltage with peak-to-peak value several times as large as the amplitude of the pulses supplied by the pulse amplifier appears across the primary. This desirably permits the step-up ratio of the transformer to be reduced.