Door Knob Touch Alarm Circuit

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Introduction

Safety first! This is the sentence that we all have heard in our lives. Whether it’s the safety of heath or material both are important in this era. So, the safety of our homes, museums, and bank lockers are necessary. Many people use watchmen for this purpose but many times watchmen also get attacked by intruders. And, since we are living in the technological era, therefore, it is great to use technology for the safety of our lives. Hence we require an effective alarm that can easily detect even the touch of a person. So, in this tutorial, we are going to “Door Knob Touch Alarm Circuit”. We are using IC555 in this circuit.

ne555-timer-ic

Hardware Components

The following components are required to make Door Knob Touch Alarm Circuit

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1.ICNE555 Timer1
2.Transistor BC5471
3.Buzzer 9V1
4.Potentiometer 100KΩ2
5.Electrolyte Capacitor 47μF/16V2,1
6.Resistor 100KΩ, 1MΩ1,1
7.Battery9V1
8.Connector2-Pin2
9.Ceramic capacitor0.01μF1

NE555 IC Pinout

555 timer ic pinout

For a detailed description of pinout, dimension features, and specifications download the datasheet of 555 Timer

Door Knob Touch Alarm Circuit

door-knob-touch-alarm-circuit-diagram-schematic

Working Explanation

We set up this Door Knob Touch Alarm Circuit by using 555 timer IC along with very few components that are easily available on the market. This circuit will generate an alert sound when anyone touches the doorknob. To make this circuit, your doorknob must include the conducting material. The circuit uses the 9V supply for the operation.

Application and Uses

  • In-home automation systems.
  • For the safety of bank lockers, museums, etc.
  • Security purpose devices.