So, I have this mini Christmas tree, with some fibre optics, that pulses red and white. A while back, it stopped working and I planned to fix it, but never got around to it. Until now!

I managed to cobble together a simple circuit based on a 555 timer. Here’s a shot of the test on the breadboard. Basically, it’s the 555 in astable mode, with a couple capacitors to smooth out the transitions.

The test had reds, but I put alternating red and yellow on the final circuit because yellow looked pretty good. Each side has a different size capacitor because it just pulses better that way. I managed to put this together on a little board. The wires on the right go to the LEDs.

With a little knife-work, I managed to size it up right. The wires are a little stiff, but a bit of jiggling got them in there.