I've been wanting to build a nixie tube clock for a long time, but it always seemed somehow intimidating. I'm comfortable with high voltages and electronics in general, but it was the coding aspect that put me off.
One day I ordered some Soviet era nixie tubes and K155id1 driver chips from a Ukrainian supplier. About a week later I got the items in the mail and I started designing the clock.
I have made a bunch of projects using Arduino boards, so I wasn't completely new to the environment, but I'm still far from being fluent in coding. Honestly it doesn't really even interest me and I only do it because sometimes I have to. I searched online for some open source nixie clock projects and it turned out there was plenty to choose from. I picked the one that seemed the simplest one just to get my feet wet. It certainly was simple enough and I had a functioning clock assembled on a breadboard in no time. Then I designed a simple circuit board to hold the 74HC595 shift register chips and the K155id1 nixie drivers.
I ordered a few Chinese high voltage power supplies, but one of them wasn't performing well enough and the other got fried due to a wiring mistake, so I searched again for a power supply that I could build over the weekend from readily available parts. I found a design based on the 555 timer chip, and decided to build one just so that I had a power supply to test the clock with. The biggest drawback of the 555 power supply is that it's not incredibly efficient, it produces a lot of heat and it just simply wastes energy. I designed a circuit board, etched it and populated it and in less than 2 hours I had a working power supply.
In the final clock I ended up using a power supply kit with the STM 063AC chip. This power supply is quoted to have up to 85% efficiency, so that's pretty good. Definitely better than my 555 power supply board.
The clock is built around an Arduino Nano clone board, a DS3231 Real Time Clock (RTC), Soviet IN-12 nixie tubes, K155id1 nixie drivers and 74HC595 shift register chips. The clock was built inside an Ikea Godmorgon plastic box made from recycled PET plastic bottles.
Here are a few pictures of the clock and I also shot a few videos you can find on my YouTube channel: