I have been meaning to play around with MQTT for some time now, and finally decided to take the plunge one evening last week. I had three cheap home temperature and humidity sensors, and was bothered that they often didn’t agree. Surprisingly, while the analog one had a calibration adjustment in the back, I have no idea how to calibrate the two digital ones. I took this as a sign that it was time to learn MQTT and be able to install my own, accurate sensors. Of course, I began by ordering the cheapest sensors I could find, but I can always upgrade later on.
We know, we know. They are bad for you. You shouldn’t start, but some people do love a cigar. And a fine cigar is pretty particular about drying out. That’s why tobacconists and cigar aficionados store their smokes in a humidor. This is anything from a small box to a large closet that maintains a constant humidity. Of course, who could want such a thing these days without having it connected to the Internet?
This fine-looking humidor uses a Raspberry Pi. When the humidity is low, an ultrasonic humidifier adds moisture to the air. If it gets too high, a fan circulates the air until it balances out. Who knew cigar smoking could be so high-tech? The humidity sensor is an AM2302. There’s also a smart USB hub that can accept commands to turn the fan and humidifier on and off.
The wooden cabinet was an existing humidor, apparently. [Atticakes] says he spent about $100 total but that a commercial equivalent would have been at least $250. You can find his source code on GitHub.
If you are vehemently anti-cigar, we should point out that there are other uses for such a device. Because of Denver’s low humidity, for example, the Colorado Rockies baseball team store game balls in a large humidor.