This circuit activates a relay when the supply voltage drops below the value set in the trimpot. The transistors can be the BC548 and BC558 and the 6 V relay. The circuit was found in a 1999 Poptronics.
This circuit was found in the Electronics Experimenter Handbook from 1991. The sensor is a diode...
This circuit can be used on audio, video, or data links to receive modulated infrared signals. The gain is...
With this circuit it is possible to obtain a voltage modulated in amplitude with a maximum current of...