On the front of a building in New York City, above a branch of the ubiquitous Starbucks coffee chain, there is a clock. It is no ordinary clock, the 200 Water Street clock is an art installation created by the artist [Rudolph de Harak], and consists of 72 lighted numbers which are illuminated in sequence to show hours, minutes, and seconds. It is a landmark of sufficient fame that [Jason Ben Nathan] and [Eldar Slobodyan], Cornell University students of [Bruce Land], decided to make their own tribute to it as their course project.
It’s a fairly straightforward build, thanks to the use of Adafruit Dotstar multicolour LED strips which are populated with APA102 pixels. Behind the scenes is a PIC32 microcontroller, and the time information comes from an off-the-shelf 60kHz WWVB time signal receiver. There is also a temperature sensor, for a handy second function.
The front panel is a piece of ply with the required numbers nicely laser-cut. All the schematics and code are available, should you fancy your hand at building your own version of the clock.
If you are curious about the real-life clock here’s an image. But you get a much more interesting perspective if you stand in front of it. If you just can’t go there, get an approximation through the wonders of Google Street View.