| Type | vacuum fluorescent display (VFD), not a Nixie |
|---|---|
| Made | Soviet Union |
| Digits | eight seven-segment digits with decimal points, plus one symbol position |
| Colour | jade green |
| Filament | 5 V |
| Pins | 22 |
People find the IV-18 clocks by searching for Nixie clocks, and it is worth saying plainly: the IV-18 is not a Nixie. It is a VFD — a vacuum fluorescent display. Instead of glowing gas, a heated filament sends electrons onto segments coated with phosphor, and the phosphor glows a jade green that no LED panel reproduces.
All the digits sit inside one long glass tube: eight seven-segment digits, each with a decimal point, plus a ninth position at the left for a dot and a dash. The clocks show hours, minutes and seconds on it.
Where they come from
Soviet new old stock, never used, like the Nixie tubes.
What it needs
The IV-18 clocks run on 5 V, not the 12 V the Nixie clocks use, and come with a universal adapter with the plug for your country.
The clocks
The Divergence Meter in black ribbed plates, and the acrylic and metal version that leaves the board on show.
Figures are from the original Soviet factory labels in the tube-tester.com datasheet archive.