Is my MQ-2 gas sensor analog or digital?

Question

I have this MQ-2 gas sensor for an Arduino Uno:

I found these two articles about how to use it:

• https://create.arduino.cc/projecthub/Aritro/smoke-detection-using-mq-2-gas-sensor-79c54a
• http://www.instructables.com/id/Ardunio-Smoke-And-Gas-SensorMQ-2/?ALLSTEPS

But I need to know if the sensor is analog or digital. Also I would like to know what is the blue switch for.

This questions help me a bit:

It says that he use an analog sensor. But as this sensor is not mine I don't want to brake it or burn it.

Answer 1

Your sensor is analog. I have the same one. By the way, there is no chip on board, so it cannot form a digital signal ;)