Found in old American documentation, this circuit is intended for the control of heating elements. The SCR must have current according to the controlled load. Transistors are from the time.
This interesting circuit was found in an Argentinean Radio Chassis Television magazine from March...
This circuit was suggested by Harris in documentation from the 80's. The circuit makes use of...
This circuit is from a 1967 US publication. The configuration can serve as a basis for designs...