This is a clock powered by a Raspberry Pi Zero W. It fetches current time by NTP and must be connected to a WiFi network to display the time.
The time is displayed on six IN-14 nixie tubes driven by six 74141. No multiplexing! The intensity can be adjusted by PWM.
There are in total five PCB's in this project. All boards are drawn with KiCad 8.0.
Bottom lid, no electrical function.
The main board, it hold gpio-expanders and driver IC's for the tubes. It also connects to the PSU board, Raspberry Pi and the nixie tube board.
Power supply board, creates 5V DC and 170V DC from 12V DC. The 170V is created by a step up converter built using a MAX1771 IC. The 5V is created by a integrated switched regulator.
Upper board on which all tubes are mounted.
Top lid, no electrical function.
The clocks software is written in Python. It's just a simple poll loop that set the new time on gpio's on the gpio-expanders every time the second changes. It's started as a systemd service at boot time.
To install the software on the Raspberry Pi, copy the ./sw folder to the Raspberry Pi and install the software by:
$ sudo ./clock-setup.sh
$ sudo reboot
NOTE: ./sw/timesyncd.conf is an example.