Oct 18 2009
A man named Howard Pounds was considered by some in Australia to be a master horologist, or watchmaker. Possessing a surgeon's touch and the patience of the mountains he was one of the rare few knowledgeable enough to repair ladies' watch movements. His talent with clockwork mechanisms was so sought after that he was not permitted to fight in World War II because the Toowoomba Foundry required his abilities far more. Sadly, this master of the most arcane of mechanical arts went beyond in the year 2005. Four years after his passing, Howard's grandson Paul constructed a fitting tribute: a fob watch based upon SMT electronics rather than held-cut cogs. Paul took a case from an antique hunter watch and spent two years constructing a circular printed circuit board to fit inside. One hundred and thirty-three SMT LEDS, each less than 2mm in length and a fraction of a millimeter in width were fit into a series of concentric rings in lieu of the hour, minute, and second hands. Rather than a collection of cogs a PIC 16F946 microcontroller was programmed to turn the miniscule LEDs on and off as required. The rest of the components - the power cell, temperature controlled oscillator, and recharging jack - can be found behind the hinged rear cover of the case. A miniature vibrating motor from a cellphone is also mounted behind the watch face to simulate the ticking of a mechanical watch. The stem and crown of the watch can even be used to set the time and alarm.
The firmware after compilation is only two kilobytes in size. Granted, this is more a limitation of the demo version of the development environment, but that's still a nifty hack.