It’s About Time
Jeff Geerling built a GPS-synced clock for his mini rack using a Raspberry Pi Pico 2 and 3D-printed parts to achieve microsecond precision.
For most of us, looking at our wristwatch or phone is a perfectly good way to check the current time. But for Jeff Geerling, that’s not going to cut it. He regularly runs experiments that require timing so precise that it is beyond the comprehension of us mere mortals. He likes to have these clocks built right into his mini racks in his home lab for convenience, but at present, these clocks only show NTP time.
Geerling is also in need of a clock that shows GPS time, so after routing some cabling into his lab from an outdoor receiver, he started hacking together a solution. It is built around the Waveshare Pico-GPS-L76X, which is a HAT for the Raspberry Pi Pico microcontroller. He hooked it up to a Pico 2, then attached a seven-segment display to show the current time, as provided by GPS signals.
That’s all that was needed as far as the electronics are concerned, but Geerling still wanted to have this clock mounted in a mini rack. To make that happen, he first 3D-printed a replica of a blanking panel. But this panel also had an opening for the display to poke through and holes to mount the other hardware to the back with screws. Once installed, all that is visible is the seven-segment display.
Displaying GPS time may be a niche project, but you could use similar methods to include a display in your mini rack for just about any other purpose as well. It could show CPU or memory utilization, for instance. What would you like to monitor from the front panel of your mini rack?
R&D, creativity, and building the next big thing you never knew you wanted are my specialties.