This circuit can work with voltages of 12 V also just changing the relay for a sensitive type for this voltage. The sensor is a phototransistor, and the transistor can be replaced by an equivalent such as the BC548.
This circuit can work with voltages of 12 V also just changing the relay for a sensitive type for this voltage. The sensor is a phototransistor, and the transistor can be replaced by an equivalent such as the BC548.