The experiment is for switching an acoustic sounder as a rain alarm after a predetermine time. It may, however, be tinkered for a number of other applications. Needless to say, this is a simple ...

Using an ESP8266 programmed via the Arduino IDE, [OttoNL] hooked up a light dependent resistor, a rain sensor, and the all-round workhorse BME280 for temperature, barometric pressure, and humidity ...