I built a model TARDIS for a friend’s birthday. It even has a light on top that blinks at roughly the same frequency as the real one! I made it with a simple CMOS inverter oscillator circuit, 3-AA batteries, and a power switch. I had ideas for some other features, like sound triggered by pressing the “St. John Ambulance” logo on the front and a light-blinking sequence that would basically simulate a takeoff; but that would have been a hell of a lot more work and possibly would have kept me from finishing it anytime soon.
