Customer:
I didn’t find a .ino file for the MQ138 sensor. Can you provide one? I want to measure acetone level.
Originally submitted via email support on 15 August 2024. Migrated to the forum for community visibility.
Soldered Support:
The MQx library should work for this sensor in the same way: GitHub - SolderedElectronics/Soldered-MQ-Gas-Sensor-Arduino-Library: Library for all MQ sensor Soldered Boards. · GitHub
The MQ135 example should work just the same: Soldered-MQ-Gas-Sensor-Arduino-Library/examples/native/MQ-135/MQ-135.ino at main · SolderedElectronics/Soldered-MQ-Gas-Sensor-Arduino-Library · GitHub
The only uncertainty is the values you compare to - what the baseline voltage equivalent to PPM/PPB is for this specific sensor.
If this doesn’t work well, here’s an alternative found on GitHub: GitHub - Marta-Barea/arduino-MQ138-gas-sensor: Source code for MQ-138 gas sensor with Arduino UNO · GitHub