Gravity: Analog Alcohol Sensor (MQ3)

This is an Arduino Alcohol sensor. It uses a MQ3 probe which can be used in a Breathalyser. It has a high sensitivity to alcohol and less sensitivity to Benzine.

The sensitivity is able to be adjusted by the potentiometer. The output is proportional to the density of gas. You can use analog reading to read the data from this sensor.

To ease the difficulty of using this sensor, a Gravity Interface is adapted to allow plug&play. The Arduino IO expansion shield is the best match for this sensor connecting to your Arduino microcontrollers.