This is an easy musical alarm circuit that produces a musical tone when water or some conducting liquid comes in contact with the two sensor wires provided. The circuit is based on four transistors and one melody generator IC (M 3482).
When water comes in contact with the sensors wires A & B, the base of Q1 gets connected with the negative and it conducts. This makes Q2 and Q3 ON. When Q3 is ON the power is available for the music generator circuit and it starts producing 12 totally different melodies one after another. The music continues as long as there's water between the sensor wires. The POT R12 can be used as a volume controller.
When water comes in contact with the sensors wires A & B, the base of Q1 gets connected with the negative and it conducts. This makes Q2 and Q3 ON. When Q3 is ON the power is available for the music generator circuit and it starts producing 12 totally different melodies one after another. The music continues as long as there's water between the sensor wires. The POT R12 can be used as a volume controller.
