This alarm circuit was found in April 1975 Radio Electronics magazine. The circuit uses a 12 V power supply and relay but can be modified to work with other voltages.
This super regenerative 1-transistor receiver was obtained in an American documentation from the...
The purpose of this circuit is to turn off a lamp after a few seconds or minutes depending on the...
In this circuit we have two oscillators, one controlling the other, using the 4 NAND gates of the...