24V WiFi Christmas Lights Controller

While I was looking for a way to decorate my Christmas tree I noticed that there are a lot of modern LED light strings and a lot of DIY open source projects that use the WS2812 addressable LEDs but I wanted to make something a bit different

I wanted to reuse my "vintage" 24V light strings, the ones with incandescent bulbs that are usually controlled by a rectangular green box with a single button. By pressing the button you cycle through the different animations

They look something like this

They are powered from a 24V AC transformer and they are wired with a common wire + a wire for each set of lights.

I made this circuit board to control them wirelessly instead :)

The board uses an ESP-12 module for the WiFi connectivity, lights are controlled by BT149 triacs, this way it's possible to make custom animations, for example: fading lights, blinking lights, slow and fast movement, and much more

The input power is still 24V AC so the original power supply can be reused, only the wires need to be cut and connected to the terminal block

I used colorful silkscreen with a Christmas themed illustration on the back side since it looks pretty cool, not really necessary for this project but it's a nice easter egg if you flip the board over :)

The ESP chip can be programmed on board using the 4 pin header, there are 2 buttons to cycle through animations (next/previous animation) and a spot to mount an optional photoresistors (to automatically turn off the lights during daytime)

All components except the WiFi module are through hole for an easy DIY project!