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 ...

The eBay hacker favorite, the so-called DHT22 module, doesn’t fare all that well, with one of six that [Robert] tested being basically horrible, and three of them breaking within two years of use.

DHT22 humidity sensor 1 Articles . Coin-Op Weather. July 8, 2015 by Dan Maloney 1 Comment ... temperature and humidity sensors, an RTC, and a Bluetooth module for uploading data to a phone.

Goal: Control lights and appliances using relays, sensors, and a web interface. Components Needed: Raspberry Pi 4. Arduino Uno. 4-channel relay module. PIR motion sensor. Steps: Use Arduino to handle ...