Capacitive Relay (T1527E)

Found in Popular Electronics from August 1956 this sensitive two-tube relay is powered directly from the mains power supply.

100 kHz XTAL Oscillator (CB24031E)
This two-transistor emitter-coupled oscillator circuit with capacitive feedback was found in the...
Light and Sound Effect (CB18136E)
This simple circuit produces sound effects given by the 4093 oscillators and switches LEDs...
Crossing Signal For Railroad Modeling 3 (CB3856E)
This circuit uses two sensors that are placed at the intersection of a miniature railroad, causing the LED...