Nixie tubes are unique cold cathode lamps filled with gas, commonly neon and argon, used to display numbers or symbols. With a common anode and multiple cathodes, applying voltage lights up the desired character. While no longer manufactured for factory use, nixies are experiencing a resurgence, especially in retro digital clocks. Some designs incorporate modern elements like LED backlighting and microprocessors. Despite their initial use in industrial equipment, nixies are now popular for clock enthusiasts. Some Soviet nixies, like the IN-18 with 4cm digits, are highly sought after. The lifespan of nixies can far exceed the manufacturer’s estimates with proper care.
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