This circuit was found in the 1991 Electronics Experimenter's Handbook. It activates a relay when light shines on a sensor.
This circuit can be used to receive signals from CB18636E and other modulated light transmitters in this...
Due to its low working voltage, this circuit of an old EDN can be associated with a...
We found this circuit in a 1983 English magazine, but it can be easily assembled with the BC548...