Another side-project – this time a Local/UTC clock for the shack using boards I purchased through a Kickstarter project:
ESPixel Clock since they are designed around Expressif’s ESP32 module and use WS2812 addressable LEDs (aka pixels). The ESP32 is wifi-enabled, so it can be kept in sync using NTP.
I am thinking of using the pair of boards – in a ham shack it is really nice to have both an accurate local time clock, but to also have a UTC clock showing. It is also neat (but not necessary) to show an indication if something is transmitting.
The design is simple, 86 WS2812B mini LEDs arranged into four 7-segment digits with a colon between each pair. Simply connect to any microcontroller to the 5V/D_IN/GND pins just like you would any addressable LED (aka NeoPixel) strip. I’ve also included provisions (3.3V regulator, passives, auto-reset circuit for programming) to add an ESP32 module to the back. Pins are broken out on the back for future expansion such as a photoresistor, I2C real-time clock, speaker, buttons, etc. They will arrive with precut pieces of black LED acrylic, specially designed to let light pass through. The ESP32 is wifi-enabled, it can be kept in sync using NTP
My idea is to put two boards, one offset to local and one at UTC side by side, and to trigger a color change when a transmitter is keyed. Elegant would be to use RF sensing to trigger, but expedient would be to sense of the PTT (push to talk) keying outputs from the transceivers in the same way as they might trigger an HF amplifier.
If sensing from the PTT I would do a different color change based on which radio was transmitting (I’m using three and planning for four).
That the clocks will sync to NTP should limit any local/UTC minor variance and make the displayed time close enough to match software doing time sensitive digital modes like FT8/JS8Call.
Again I’m excited to have the clocks inbound and if I can keep focus to get cases & at least the basics up and running I’m hopeful they will go up on the wall right away, rather than slotting into my project queue.
Link to the project: https://www.kickstarter.com/projects/etap/espixel-clock/
Matt has written a basic Arduino sketch for the board which fetches the time over WIFI and displays it on the board:
The PCB is 122mm x 48mm (4.8 in. x 1.9 in.)and under 3/8 inch thick assembled and has mounting holes at the four corners.
Reddit user u/symonty created this case design for 3D printing: https://www.thingiverse.com/thing:4090591 and https://www.prusaprinters.org/prints/22180-espixelclock-simple-enclosure-case
There is a schematic of the board at Matt’s github: https://github.com/mattncsu/Neo7SegmentClock/blob/master/Neo7Segment3535-sch.pdf