This circuit was obtained in an English publication of 1975. It is a circuit that stabilizes an alternating sine-wave voltage. The power depends on the transformers with secondary 42 V and a maximum current of 5 A. The transistor 2N3055 must be equipped with an excellent heat radiator. We made some changes to make it possible to use current components. The adjustment of the output voltage is done in the potentiometer within the range allowed by the transformers.
