Found on a 1969 EDN this circuit switches a current from a digital control signal. The impedance of the circuit ON is approximately 10 ohms. Modern equivalent transistors may be used.
This oscillator circuit for sinusoidal audio signals with operational 741 requires a symmetrical power...
Found in a 1974 Radio Shack documentation. This circuit must have a connection to the ground of...
This sensitive circuit detects the live pole of a power grid or outlet. The circuit makes use of a high...