Introduction
This experiment demonstrates how to measure alcohol content in the air using the MQ-303A sensor.
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Components Needed
- MQ-303A Alcohol Sensor
- Arduino
- Jumper Wires
Circuit Setup
- Connect the VCC and GND pins of the MQ-303A to the 5V and GND on Arduino.
- Connect the analog output pin of the MQ-303A to an analog input pin (e.g., A0) on Arduino.
The MQ-303A sensor will measure the alcohol concentration in the air and send the data to the Arduino.
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Code for Alcohol Content Detection
Upload the following code to your Arduino to measure the alcohol content in the air:
const int alcoholPin = A0;
void setup() {
Serial.begin(9600);
}
void loop() {
int alcoholLevel = analogRead(alcoholPin);
Serial.print("Alcohol Concentration: ");
Serial.println(alcoholLevel);
delay(1000);
}
Explanation
The MQ-303A sensor detects alcohol in the air, converting the detected concentration into an analog value which is then read by the Arduino.
Troubleshooting
- Ensure the sensor is properly connected to the Arduino.
- If readings are inconsistent, check sensor calibration and check for interference from other gases.