We found this solid-state relay circuit that can function as a shield in a Radio Electronics magazine from December 1989. The optocoupler is a phototransistor type.
This LC oscillator with complementary transistors was found in an English publication from the...
This strobe light circuit with xenon lamp was found in a 1995 documentation. The circuit is...
Found in na 1970 EDN this circuit has a parallel regulation providing a symmetrical output of 15 V....