Build a WiFi Switch Directly Into Your String of Outdoor LEDs

LED fairy lights are a great way to class up your garden or yard, but can offer a couple of challenges. Many are meant to be plugged into mains power through a DC power supply, which can be a problem if you don’t have any outdoor outlets. Luckily, there are 5V strings of fairy lights meant to be powered through USB, which you can use with a battery power bank. If you go that route, Albert David has a guide on building a WiFi switch right into the LED string.

This is a great setup if you want to light up a garden without easy access to an outdoor electrical outlet. You can put the string of LED fairy lights wherever you want, and run them off of a portable USB power bank. With the addition of the WiFi switch, you can turn them on and off remotely without having to disconnect that power bank. And, the switch is tiny and streamlined, so it’ll blend right into the rest of the LED strip.

To build this, you’ll need a string of LEDs that is meant to be powered by USB. Normal LED strings will probably consume too much power, so you need the low-consumption USB kind. You’ll also need the USB power bank, and an ESP-12F (which is based on the popular ESP8266 module). There’s really only one step to the project: build the smart switch.

The goal here is to give the ESP-12F both a male and female USB-A connector, so it can be placed in between the LEDs and the power bank. You’ll also add a transistor, a button, a couple of diodes, and a few resistors for the switch circuit. David provides detailed instructions on how to solder these. Then just program it, seal it up with hot glue, and it’s ready to use!