3 Review(s)

This device can be used as water level indicator. It is an prototype device which can be assembled at the top of the water tank, if the tank gets full, it will start alerting. If the water level goes above a certain level, the probe1 and probe2 both gets short circuited hence the transistor Q1 gets turned off. As the transistor Q2 gets turned off, Q1 gets turned on hence buzzer and led get turned on. There is the simple conecept of switching action of transistors.