Maker builds five-segment argon plasma display inspired by vintage Panaplex design
Key Takeaway
A maker created a prototype five-segment plasma display using argon gas with platinum-titanium cathodes sputtered onto glass, driven by a 74141 Nixie driver IC.
Summary
The project by [Witchcraft and Alchemy] draws from the Burroughs Panaplex, a lesser-known pre-LED display technology. The prototype uses an indium-tin oxide anode on glass with titanium and platinum cathode layers to prevent flaking. It produces a purple glow in a vacuum chamber when driven by the vintage 74141 driver. A self-contained version failed quickly, prompting plans to replace tape and epoxy sealing with a gasket and conductive vias for a more permanent vacuum.
What makes this plasma display different
- Gas: Argon rather than neon used in traditional Nixie tubes, with plans to switch to a Penning mixture for improved performance
- Cathode construction: Titanium adhesion layer followed by platinum to prevent flaking caused by glass-platinum molecular incompatibility
- Anode: Indium-tin oxide (ITO) layer deposited directly on glass
- Driver: 74141 Nixie driver IC, a vintage BCD-to-decimal decoder/high-voltage driver
- Current prototype: Five segments only; future revision targets seven segments with improved sealing via gasket and conductive vias
Original reference: hackaday.com →