The picture shows my home-built digital clock, using Nixie tubes for readout. In contrast to most other nixie clocks being built these days, this clock does not use any transistor or IC for controlling and driving the tubes. Instead, the driving logic is built from trigger tubes, together with resistors, capacitors and silicon diodes. A video is on youtube.

This project is a followup to a similar clock I built between 2002 and 2007, documented on its own page. That clock used regular NE-2 style neon lamps as logic elements. Unfortunately, after a while, as these lamps aged, the clock became unreliable and unusable.

The new clock uses trigger tubes, of the МТХ-90 type (that's in Cyrillic characters; transliterated to Latin script it's MTH-90), which are widely available as "new old stock" on Ebay. Trigger tubes are essentially regular neon lamps with an extra "trigger" electrode, which can be used to ignite them. However, in this circuit I don't use the trigger electrode.