Nixie clock
Once, when I was looking for something on the attic, I have found lots of nixie-tubes. After that I started to thinking about that what could I do with these. Soon, I figured out that I need just a 12V -> 150V high voltage power supply and a 74141PC driver IC which is a binary to decimal converter. After these stuffs arrived from ebay, I started to assemble a test PCB.
Clock
Since it works well, I started to develop the main PCB and the full code for an Atmel ATMega328P microcontroller (which is also used by Arduinos).
Under Construction
To show the current and precise time, I am using a DS1307 RTC (real time clock) module. It is configured and actualized on PC at the first time, and a 3V Li-Ion battery keeps the clock ticking when the module is powered off.
Early Experimentation