This PIC16F84A-based gas detector project has capability to sense many different types of gases like smoke, liquefied gas, butane and propane, Methane, alcohol, hydrogen, etc. This simple gas leak monitoring project only need few component and easy to build. It uses Smoke Sensor Module GH-312 to detect gas or smoke. For warning sign, the project is equipped with LED, LCD and Piezoelectric.
Rui Cabral, project designer explains that during testing progress, the sensor is able to detect the gas from soldering iron. The system will trigger a flashing led warning, sound (produced by a small piezo), and message “Found Gas” on LCD. When the air is clean (no gas), the circuit will return to its normal state and turning off LED, piezo sound and LCD display “Sensing No Gas” message. Project : Schematic, firmware (hex).