In this circuit, the infrared emitter IRED1 is modulated by connecting its anode (A) to ~38kHz signal yielded by D9 of the Arduino Uno (TP1) while its cathode (K) to a ~1kHz signal available at D8 of ...

You can even build yourself something simple based on an Arduino Uno! The build uses Panasonic’s cheap “Grid-EYE” infrared array as the thermal sensor, in this case, a model with an 8×8 ...

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 ...