Power supply failure alarm circuit


This is very useful circuit for you.Because through this circuit we will be able to know about a power failure.Here We have done some modification,it's nothing but this circuit doesn't want an extra power supply for the alarm circuit.Because after the power failure alarm circuit doesn't operate with out power,But here we have attached a capacitor so through that after the power failure this capacitor can operate the alarm circuit.After giving 5V to 15V power.Then tune VR1 till alarm goes on position to off position


Note

# Give 5v to 15v power supply for this circuit.
#Tune VR1 after giving power.

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