Uploaded June 2020 | Updated September 2026, 2 weeks ago

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You can find the code + schema on project page, below is the link:

arduino-projects-free.blogspot.com/2020/06/mq-135-sensor-gas-displayed-on-4-digit.html
Code: drive.google.com/file/d/1FdDe2mKOoVDafBRctjlaqyQZHjPN4Kiw/view?usp=sharing


High sensitivity to CH4 and Natural gas
Slight sensitivity to alcohol, smoke
Fast response
Stable and long life
Simple drive circuit
VCC - 5V
GND - GND
A0 - A0

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#3tawi
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#Nano V3