| Made by | Gazotron factory, Rivne, Ukraine |
|---|---|
| Digit height | 40 mm |
| Read from | the side |
| Decimal point | none |
| Bulb | 30–32 mm across |
| Pins | 14 |
The IN-18 is the largest of the Soviet Nixie tubes. The digit is tall enough to read from across a room, which is why it went into the clocks people remember. It works exactly like the smaller tubes — wire digits in neon, glowing orange — just at a scale the others cannot reach. It shows the digits 0 to 9 only, with no decimal point, and reads well from a wide angle.
Why they are rare
The IN-18 was made at the Gazotron factory in Rivne, Ukraine, which stopped making it decades ago, so every one in circulation is at least that old.
Buying one
Tested IN-18 tubes are in the shop — new old stock, never used, and checked on a live board before they ship. They fit socketed IN-18 clocks, including the IN-18 clocks I have built. They do not fit IN-14 or IN-12 clocks.
Figures are from the original Soviet factory labels in the tube-tester.com datasheet archive.