Electronic Traffic Signal
Built simultaneously with the Mosaic Super Mario Bros. Lamp, this project was a real challenge to say the least. Inside this hollow yellow structure is a “brain” — a microchip from a model railroad set, which controls three LED spotlight bulbs rigged up in a series and powered with an AC adapter. The bulbs then shine behind a grid of Technic bricks with transparent colored plates in the holes — in the same “Lite Brite” fashion as the Mario Lamps. I spent about a month experimenting with the bulbs and electronics, to get failed results, when I eventually learned that I needed to remove some of the resistors from the circuit board.
Build your own (tutorial on Instructables) • Review on Hack A Day