The soil moisture sensor module , built around the LM393 comparator, gives an active-low (L) level output when the soil is dry (determined by a pre-setted threshold value). This digital output (wet ...

In a way, the magic of a soil moisture sensor’s functionality boils down to a simple RC circuit. But of course, in practice there is a bit more to it than that. [rbaron] explains exactly how … ...

I made the two soil probes using 5/16 x 2-inch full-thread steel bolts, 20-gauge wire, ... (according to a comparison with a commercial soil-moisture sensor), and 661 in a drier pot.

The moisture sensor is of his own design. It uses two building screws embedded in foam. These are pushed into the soil and a resistance reading indicates moisture level.

We report the design and installation of a distributed soil moisture sensor network in a riparian zone within the Whitewater Basin in Central Kansas. The soil-moisture monitoring network used in this ...