Introduction: Glass Breaking Alarm / Burglar Alarm
This circuit can be used for sounding an alarm to detect the breaking of a glass window by an intruder, even when the intruder ensures there is no sound of the shattered glass.
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Step 1: Here Is the Project in Action
Step 2: Required Component List
1x Bread Board
1x Red LED
1x Potentiometer (1Mega Ohm)
1x Electrolytic Capacitor (10uF)
1x Timer IC NE555
1x 3.3K ohm Resistance
2x 330k ohm Resistance
1x 1K ohm Resistance
1x 10k ohm Resistance
1x BC548 Transistor
1x 100nF Ceramic Capacitor
1x 10nF Ceramic Capacitor
1x Piezo Sensor
1x 9volt Battery
1x Battery Snap
Step 3: Placing the Transistor on Breadboard
The first step you need to do is place the transistor on one side of the breadboard, you have to place it on one side so there is enough space to add the rest of the components without trouble.
Step 4: Transistor Connections
Place the resistors of the value as shown in the image and do the connection. the black wire is the ground wire.
Step 5: Piezo Sensor Connections
The image shown in the step is an image of a piezo buzzer. In the library, the piezo sensor is not available so we use the piezo buzzer instead of the sensor.
Step 6: Power Rail Connection
The horizontal rails on the breadboard are called power rails. The power rails are not connected in a full-size breadboard. The red is the positive of the power supply and the black is the ground of the power supply.
Step 7: Place the IC NE555
Next, you need to do is place the IC NE555 on the other side of the breadboard, you have to place it on the other side so there is enough space to add the rest of the wire and components without trouble.
Step 8: Transistor and NE555 Connection
Connect the collector of the transistor to the input pin (Pin2) of the IC NE555 through a ceramic capacitor of value 100nF. The full connections are shown in the images.
Step 9: IC NE555 Power Connections
Connect the pin1 of the IC to the ground and the pin4 & pin8 to the positive rail of the power supply.
Step 10: The LED Connection
Connect the LED to the output pin (pin3) of the IC through a series resistor. The series resistor is for limiting the value of the current. Black is the ground wire.
Step 11: Buzzer Connection
Connect the buzzer to the output pin (pin 3) of the IC. The buzzer is also a polar component so connect the positive wire to the IC and negative to the ground.
Step 12: IC Pin 6 & 7 Connections
Short the Pin 6 and 7.
Step 13: Electrolytic Capacitor Connection
Note- Electrolytic capacitors are polar components so double check the connection everytime you connect a polar component.
The silver side of the capacitor is the negative side and the other is the positive side.
Connect the positive terminal of the capacitor to the pin 6 of the IC and negative to the ground.
Step 14: Pot Connection
Connect the potentiometer in the same way as shown in the image otherwise, it will be difficult for you to make connections.
Connect one terminal to the pin6 of the IC and rest two to the positive of the power supply.
Step 15: Pin 5 Connection
Connect the pin 5 to the ceramic capacitor of value 10nF and ground the other pin of the capacitor.
Step 16: Power Supply Connection
Connect both side power rails. The black is the ground rail and the red is the positive rail.
Then connect the battery to the circuit.