Say, you’re starting your electronics journey with a few projects in mind. You have an ESP8266 board like the Wemos D1, a Li-Ion battery, you want to build a small battery-powered sensor that… ...

For those following along at home, [WhisleyTangoHotel] provides a hand-drawn diagram to show how everything connects together in his Morse timepiece, ... but any ESP8266 would work in its place.