National Union GI-10 'Inditron'  
Written by Accutron on 2017-03-21  

Introduced in 1954, the National Union GI-10 'Inditron' is an early Nixie-style numerical indicator tube, developed in parallel to (and possibly predating) the successful Burroughs design. Unlike a conventional Nixie tube, the GI-10 does not include an anode mesh, requiring an adjacent cathode to be pulled high to ignite the glow discharge. Additionally, the failure-prone numeral cathodes in the GI-10 are constructed of a delicate bent wire instead of a stamped plate. The GI-10 can be inserted into a conventional 9-pin tube socket, but provisions must be made for its long center anode pin. The combination of a short lifespan, convoluted drive requirements and non-standard basing doomed the GI-10 to obscurity, while the robust Burroughs Nixie tube enjoyed wide adoption.

Special thanks to Randall Logan for providing an excellent scan of the GI-10 datasheet.

National Union GI-10 Datasheet (PDF)


National Union GI-10 under normal operation.

This article is part of the [Vacuum & Gas-Filled Displays] exhibit.

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