Abstract: A direct current-to-direct current converter is disclosed wherein a saturable core oscillator provides squarewave alternating current signals to the bases of two transistors of a class B push-pull amplifier such that the two transistors are alternately biased into conducting states. Each transistor controls the current in one section of a center-tapped primary winding of a transformer such that the alternation of conduction between transistors produces an alternating flux density in the core of the transformer and direct current is provided by rectifying and filtering the alternating current induced thereby in the secondary winding of the transformer.