Circuits similar to this can be found in this section. This is from 1967 General Electric documentation. The main SCR must be fitted with a heat sink.
This circuit uses three inverters to generate a rectangular signal whose frequency depends on R1...
This control circuit or reversible contactor was found in a 1967 General Electric manual. The...
This circuit counts from 1 to 10 or 0 to 9 using as indicators common LEDs. The circuit can be...