I spent two weeks last winter inside a workshop outside Brno, watching a sixty-eight-year-old retiree hand-stack numeral cathodes into evacuated glass envelopes. The room smelled of rosin flux and ozone. Each tube took him nearly forty minutes to assemble, and when he energized the first completed unit on his bench supply, the numerals bloomed orange against the concrete wall — not the harsh red of a seven-segment LED, but something warmer, rounder, alive with the physics of neon discharge at six hundred forty nanometers.
The Economics of Obsolescence
By the late seventies, sealed glow tubes had been priced out by flat semiconductor displays. What survived was scarcity: drawers of surplus glass, a few patient makers, and a market willing to pay for numerals that feel manufactured instead of rendered.