Nixie Tubes And Nixie Clocks

IN-18 Nixie Clock

IN-8-2 Nixie Clock

Introduced in 1955, Nixie tubes are making a resurgence as old stock that has been sitting around in warehouses, untouched are now being sourced and made available.

A Nixie tube is a cold-cathode neon discharge tube. The anode comprises of the mesh, and the multiple cathodes are the shaped numbers (or symbols), which when a DC voltage, typically 170 volts is applied, the cathodes glow red.

Nixie tubes bring with them a nostalgic feel, which contrasts today's LED based displays.

IN-18 Russian Nixie Tubes

Over many years, I have collected a small stock of Nixie tubes and Nixie era discharge tubes, which include several sets of the sought after IN-18 large Russian Nixie Tube. The IN-18 tubes feature 40mm high digits.

Pictured, are the IN-18 tubes in front of my Nixie clock that uses the smaller 18mm IN-8-2 Nixie tubes. I had modified the original kit which used the IN-14 Nixie tubes, however I am not a fan of the upsidedown '2' used as No.5.

Nixie Controller

Nixie Controller

Constructed back around 2012, the circuit is built around a pre-programed microcontroller to direct-drive 6 Nixie tubes.

The controller as well as a temperature compensated crystal oscillator (TCXO) was sourced through All Spectrum Electronics in California.

This controller was selected for its available feature rich options and also that it is able to drive the Nixie tubes directly as opposed to multiplexing the tubes. There are pros and cons to multiplexing, one is around a higher drive current to achieve the same luminous output as direct driven tubes.

By Flavio Spedalieri, 13 November, 2020