SparkFun Electronics Forum

Hello everyone,

I have Arduino Uno and the SparkFun Soil Moisture Sensor SEN-13322. I saw some tutorial that involve a HL-69 moisture sensor but also need a controller. What is the purpose of that controller? Is the controller necessary also with the SparkFun Soil Moisture Sensor SEN-13322?

Thanks,
Antennaboy

No you do not need that controller, which is an YL-38 (an amplifier / comparator module). The SEN-13322 has an on-board transistor for that purpose. Follow the hook-up guide that is with the documents