We just wanted to show some pictures about a recent project where we had to build some low-cost wireless soil moisture sensors. This post is a continuation of this other post but this time panStamp NRG is the module being used. Given its lower current consumption and wider voltage range, this sensor module should last around a year with readings every ten minutes or so.
Figure 1 : Cheap resistive soil-moisture sensor being read from a panStamp
We had to adapt the shape of the wire antenna to fit the inner space of the enclosure but we are still getting sufficient ranges for the project.
Figure 2 : The whole circuit being powered from a CR2032 battery
Configuring the right measurement and transmission interval is crucial since CR2032's 220 mAh could run out quickly.