LED filament light bulbs are somewhat interesting devices by themselves, and as hacker Andy Pugh observed, “they must be good for something.” After finally purchasing a number of bulbs with the intention of smashing their innards out for creative use (later learning the LEDs can be purchased separately), the thought dawned on him that they could make a very nice 7-segment clock.
The frame for his LED clock is made out of a bent section of brass, and the distinctive look of the device — reminiscent of Charlotte’s Web — is formed by using the power lines to suspend the LED segments inside.
His initial idea was to control each segment using 27 outputs from an Arduino Mega, but decided to use DS8880 driver chips for VFDs to simplify the setup. These chips meant that only 13 control lines were needed to handle the clock’s four digits.
In order to keep proper time, his clock references the UK’s official 60kHz radio time signal. Pugh eventually settled on an Arduino Duemilanove, after having trouble syncing with the time signal using other boards.
If you’d like to try something similar, Arduino code for the build is available on GitHub, and it can be seen in action in the video below.