I’ve always been fascinated by Nixie tubes. There is something special in them. Probably their shape, analog feel and the glowing numbers are making these tubes standing out from the new, more modern counterparts. Couple of years ago I bought a couple of IN-14 nixie tubes from AliExpress. To be more precise 3 of them. 

It was easy to decide what to use these tubes for: clock. Yes, yet another implementation of a Nixie clock. A bit boring, I know, I know… But, I wanted to implement my own version of it.

As you may know, at least 4 tubes are needed for a clock to show time in format like HH:MM. So, I had two options: order one more tube or come up with something different. Since nixie tubes are not on the cheap side I decided to use only one tube for a clock.

Short list of requirements:

• Power the clock from USB
• Use Arduino for development
• Store time on a Real-Time-Clock
• Interface the clock via Wireless
• Reuse already bought components, such as ESP8266 and DS3231

The end product is a stack of 2 PCBs where the bottom one is the control board containing the ESP with Nixie supply and the top one is the display board containing the RGB LED and the Nixie tube. 

Short demo:

Note: The demo is without the Wifi tab.