Proximity Sensor with Ultrasonic

This is an Arduino-based Proximity Sensor circuit wired using the popular HC-SR04 Ultrasonic ranging module,used here for non-contact object detection purpose. The HC-SR04 module includes ultrasonic transmitters, receiver and control circuit. You only need to supply a short pulse to the trigger input to start the ranging, and then the module will send out burst of ultrasound at 40 kHz and raise its echo.

Components:

1) Arduino UNO, Breadboard, Jumper Wires

2) Ultrasonic Sensor HC-SR04

3) LED

4) 1 kOhm Resistor [x2]

5) Buzzer Sound 5V

6) Transistor BC547