This was the first time someone asked us to build a project with nixie tubes not because of their appearance, but for the way how they work. Even more exciting was the fact that the email came from NASA!
We got together specifications for the display and started the work. The first task was to find out the maximum frequency the nixie tube can reliably switch between digits. It turned out we can go up to 100 000 changes per second, so it would be possible to calibrate 100 000 fps cameras.
Within several months, we implemented the IRIG-B 123 interface and designed the electronics. The most important person behind the electronic design was Sebastian Melzer who worked for us as an electronic engineer by then. We had to make sure the clock will identify the beginning of each new second on the IRIG signal with accuracy around 1μS. Then there was propagation delay of the individual ICs, software etc..
After 6 months of work, we had the display finished and shipped to the customer to Kennedy’s Space Center.
Dalibor, we are actively using the second clock, along with the first. It has made our testing so much easier than before.