This circuit was found in the April 1971 Radio Electronics magazine. It uses common transistors and can be adapted to use an LED or audible indicator instead of a light bulb.
This circuit was found in a General Electric documentation from 1965. The circuit is full wave for...
We found this circuit in the Texas Instruments' Linear Circuits Applications. It uses an...
In the presented circuit it is possible to vary the frequency of the rectangular signal produced. This...