General Electric suggests this circuit in a 1980s documentation. The operational of the time is FET-type input. Modern equivalents may be used.
This circuit uses a common digital clock to activate a relay at a programmed time. The circuit takes...
This simple circuit activates an alarm (buzzer) when the sensor, made up of two plates separated by...
This circuit has its frequency controlled by a 1MHz crystal. The circuit must be powered by a...