THIEF ALARM WITHOUT IC NE555

THIEF ALARM (WITHOUT IC NE555)

INDRODUCTION:-

This is the easiest way to make a thief alarm. If you know how to make an ordinary electric circuit, this circuit would be very simple than the other method.

MATERIALS REQUIRED:-

11)      Breadboard                                               1

22)      12v/230v Transformer                                1(2)

33)      Buzzer                                                        1

44)      LED                                                           4

55)      LDR(RESISTANCE IN DARKNESS       1

66)      Resistor 48 K Ohms                                   2

77)      Resistor 100 ohms                                      2

PROCEDURE:-  

Take the breadboard and connect the 12v/230v transformer to the pin numbers 5 and 10.connect the 100 ohms resistors to the pins 1b and 5b.Then connect one wire of the transformer directly to the resistors 48 k ohms leading to the +_ve terminals of the buzzer and the LED. Then connect the next wire of the transformer to the LDR’s first terminal then connect the next terminal of the LDR to the –_ve terminals of the buzzer and LED. Now switch off the light.When the intruder switches on his torch the

                                Circuit

    

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