Ray Wang at Rayshobby has been working on reverse engineering a wireless soil moisture sensor. He writes, “At the Maker Faire this year I got lots of questions about soil moisture, which I knew little about. Recently I started learning about how to build my own soil sensor, and came across this cheap 433MHz wirelss soil sensor available from Amazon. I’ve experimented with some similar wireless sensors (temperature, humidity, rain etc.), so it didn’t take me long to figure out the signal encoding pattern of this one. I wrote an Arduino program (also adapted to R-Pi) to listen to the sensor and print out the soil moisture level to the serial monitor. This provides a convenient and low-cost solution to integrate soil sensors to my home automation projects.”
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