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 ...

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 circuit is based around this Sputnik-looking standalone IR temperature sensor which, as [MakeFunStuff] aptly describes, is “a single-pixel infrared camera that picks up everything in a 90 ...