Get close enough to this raven and you’ll set off the PIR sensor, which triggers lighting and sound effects, including some spooky glowing and blinking red eyes, general cawing, and of course ...

You have an ESP8266 board like the Wemos D1, a Li-Ion battery, you want to build a small battery-powered sensor that wakes up every few minutes to do something, and you don’t want to delve into ...