The hardware is consists of an Arduino microcontroller (here an Arduino Uno R3) and a pre-wired soil moisture sensor module. The soil moisture sensor module , built around the LM393 comparator, gives ...

The alarm system is triggered when a “Logic High (H)” level signal is detected at its sensor input port. Parts required. Advertisement. Arduino Uno R3; 5mm LDR; 10K ¼W Resistor; ... Arduino Code ...

I have a schematic of a purely analog sensor like this, but the arduino gives us an opportunity to focus on the “shape” of the field, or any kind of pulsed frequency if that’s available.