“In this Instructable I’ll show you how I’ve built an LED ornament for Valentines day that I gave as a gift to my wife.
The circuit is very simple and it is based on the classic astible multivibrator that uses two transistors with two capacitors to alternatively flash two sets of LEDs. The circuit is most commonly done with just a single LED per transistor but you can add more without issues. The only difference is that the more LEDs you add the faster those blinks will be but that can also be addressed with bigger capacitors.”