The idea of this circuit is that when the device in SO1 is turned on, the device connected to SO2 automatically receives power. The circuit is from Radio Electronics from January 1985.
This circuit of a 1978 American publication monitors a telephone line by triggering a relay. The...
Found in 1965 General Electric technical documentation, this half-wave circuit controls shunt type...
The power supply shown in the figure provides voltages between 0 and approximately 15 volts, with...