The CA3020 integrated circuit was one of the first commercial types, sold in the 1960s. The circuit presented is from 1968 using a power stage with RCA transistors of the time.
Found in a 90s nHands On Electronics, this circuit triggers a relay that shuts off the load when...
Another of the many similar configurations we have in this section. This one is from a Radio...
This circuit for incandescent lamps was found in the January 1980 Radio Elecronics magazine. The...