Talk about your mixed timekeeping metaphors: there are clocks, and pendulum clocks ... this uses a single IN-12b Nixie tube at the end of a pendulum. The pendulum is kept moving by a small ...

Nixie tubes, while built during the vacuum tube era of the mid-20th century, still exist in a niche among hackers. It’s quite the task to get them up and running due to a number of quirks, so ...