Abstract: An electric control circuit for the supply of ohmic-inductive loads via direct-current pulses with changeable pulse use-ration encompasses a regulator featuring a transformer (T) wherein the transformer is designed as an autotransformer with a single continuous winding with center tap and taps symmetrical to the center tap, is connected on the primary side via electronic switches (Q.sub.3, Q.sub.4) bridged by freewheeling diodes in push-pull arrangement to a direct-voltage source (B) and, on the secondary side, is connected via electronic switches (Q.sub.5, Q.sub.6) which are symmetrical to the transformer (T) and are bridged by freewheeling diodes. Between the connection point of the connections facing away from the transformer (T) of the electronic switches (Q.sub.5, Q.sub.6) on the secondary side, and the pole of the direct-voltage source (B) which pole faces away from transformer (T), there is connected at least one series circuit of two electronic switches (Q.sub.1, Q.sub.