Internal Schematics for MQ-2 Gas Sensor Module. The Circuit Diagram for the MQ-2 Gas and Smoke Detection Sensor Module is shown below. The schematic for this module is very simple and needs a handful ...

MQ6 gas sensor is also sensible to LPG, Alcohol, and Methane etc. Here we have used Buzzer as a Smoke alarm, which is driven by BC547 NPN transistor. We have previously built Smoke Detector Arduino ...