MQ-2 Gas Sensor Module
From Wiki
MQ-2 Gas Sensor Module
Introduction
Gas Sensor MQ-2 is a sensor for flammable gas and smoke by detecting the concentration of combustible gas in the air. They are used in gas detecting equipment for smoke and flammable gasses in household, industry or automobile.
The schematic diagram of the module is as follows:
Resource
Test Experiment for Arduino
Test Experiment for Raspberry Pi