Simple door Alarm circuit


This is simple door alarm circuit.You can attach this circuit for your for your main door If somebody opens it alarm will activate.Sw1 is a Read switch.Those switches are operated with magnets.







Parts:

Q1 = BC547
Q2 = BC327
B1 = 3V Battery
R1 = 330K
R2 = 100R
C1 = 10nF-63V
C2 = 100uF-25V
SW1 = Read Switch



Note

# Don't supply more than 4.5V for this circuit

#Attach a magnet for the door frame near by the read switch

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