Prototyping the Bulbdial clock
posted Aug 28th 2010 12:00pm by Mike Szczysfiled under: classic hacks, clock hacks



We never thought about it before, but having the controls on the bottom of a clock is a bit of an inconvenience. [Alex Whittemore] mutes the LEDs on his clock each night and after a while, decided he should make the mute button into a touch strip on the case. You’ll remember that the Bulbdial clock uses colored LEDs to create the effect of a sun-dial, casting colored shadows for each hand of the clock. It makes sense that this would put off a pretty good amount of light at night. [Alex's] original thought was to use a capacitive touch sensor but complexity and cost were in his way. What he ended up with is a resistive touch switch based off of two metal strips. He used metal repair tape but suggests copper foil as he was unable to solder to tape. When your finger touches the two strips it completes the circuit for the base of a transistor, which in turn grounds the mute button on the clock. Cheap, simple, and illustrated in the video after the break.

[Taufeeq] sent in his “Circle of Light” bulbdial clock. You may remember when we showed you Evil Mad Scientist’s version a while back, and [Taufeeq] did use it as a base but he’s added some of his own little touches. Some of the changes include using a PIC with an RTC chip instead of AVR, which allowed him to shrink the board down small enough to fit behind the clock face, rather than on front. He’s even zipped everything up conveniently to help you build your own.

Evil Mad Scientist Laboratories has built the bulbdial clock, an idea originated by Ironic Sans. It’s basically a high definition indoor sundial. The LEDs arranged in a circle shine a light on the peg in the middle casting a shadow, just like a sundial. There are 3 colors of rings, allowing for hour, minute, and second shadows. This isn’t the first time that Ironic Sans has seen ideas come to reality. There were the pre pixelated reality show clothes and the sneaky histogram hidden message system. While it is a cute idea, it isn’t really new. People have been patenting this idea for a while.
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