Using two unijunction transistors, this circuit found in Electronics World generates linear sawtooth signals. The frequency depends on the capacitors being around 500 Hz.
This circuit can be used as shield or to drive powerful loads from low current switches such as...
This circuit was found in a 1968 documentation. It makes use of both NO and NC reed-switches and small...
This circuit keeps an LED on briefly when S1 is pressed. The time depends on C1. The circuit is...