This circuit for the power grid was found in the June 1969 Radio Electronics magazine. The SCR and diodes are rated according to the power of the controlled load.
This circuit appears in similar versions on this site. This is from a Popular Electronics from the 80's. The...
This two-transistor delay circuit from the 1960s was found in documentation from the time....
This circuit operates with signals from 150 kHz to 1 MHz and makes use of a known NAND CMOS gate....