Vermes
Advanced Member level 4
The device can be used as a tool for measuring the gas concentration. Sensor AF50 was used in this project – LINK. The measurement is converted by ADC and displayed on LCD in a form of percent.
Additionally, there is a temperature measurement implemented by 1wire using Dallas sensor in the program.
In addition, there is a possibility to set the level of alarm, which activates after exceeding the set threshold.
Ability to calibrate the sensor gives the convenience that even at full gas concentration you can set the sensor to 0% and check if the concentration changes.
The system can be expanded with another sensors (for other gases, pressure and noise) and the ability to remember the biggest/smallest results in external memory. In this way you can make some kind of multimeter.
Pictures of the subsequent stages of creating the system (from propox test board, the contact plate to the finished digested system and ready device).
Link to original thread (useful attachment) – [ATMEGA8] [C] Czujnik metanu na czujce AF50