Burglar Alarm Circuit


This is a very useful circuit for you all.This is actually little bit different circuit.Because this circuit has used little bit advance knowledge.This circuit operates with 9V.You can fix this circuit for a door(SW1).Its ok though people use this door.But if some one keep opened it more than 30 seconds the alarm begins to ring.only users should know they should closed the door before 30 seconds.Think different way and use this in different way.

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