Nifty electromechanical Vane display

Eastern Star Geek posted a complete electromechanical clock design for the Vane clock digits we covered earlier:

The displays in question are of a 7 segment electromechanical design.  These are not light-up displays, but rather, reflective.  Each segment is a “vane” that has been painted a bright contrasting color, and mounted on a hinge, such that it can be swung into, or hidden from view.  This is accomplished with two solenoid coils sharing a common pin.  In order to show a segment, the Show coil must be pulsed for about 50mS, which will flip the vane into view.  A permanent magnet keeps it there, even after the coil is switched off.  To hide the segment, just pop the Hide coil for 50mS.  Pretty simple, no?

Via the forum.