Simple water sensor can be used to detect soil moisture when the soil moisture deficit module outputs a high level, and vice versa output low. Use this sensor produced an automatic plant watering device, so that the plants in your garden without people to manage.
2 adjustable sensitivity blue digital potentiometer adjustment (Figure)
4 Operating voltage 3.3V-5V-
module dual output mode, the digital output is simple, more accurate analog output.
A fixed bolt hole for easy installation
7 small plates, PCB size: 3cm * 1.6cm
8 power indicator (red) and digital switching output indicator (green)
9 comparator LM393 chip, stable
Two small plate interface description (4-wire)
2 GND external GND
3 DO small board digital output interface (0 and 1)
4 AO the small plates analog output interface
Three instructions for use