The ubiquitous digital displays on alarm clocks, watches, cable boxes, calculators, and microwaves have been the same for decades: boxy, red letters on an LCD screen. Since the 1970s, LCD displays have been ever-cheaper and (not coincidentally) everywhere. Numbers are displayed by activating combinations of seven light-up segments. Taken in groups, these segments can suggest a number or symbol, but it is impossible to form a curved line and so the display is fairly limited. Before the LCD screen became widely available, the best way to make a digital display was with a Nixie tube. Nixie tubes are glass bulbs containing layers of pre-shaped numerals (or letters, signs, or symbols) that can be displayed one at a time. Although more tubes are required for applications in which several characters must be displayed at once (as in a clock), and the tubes themselves can be quite fragile, the display is more legible and aesthetically pleasing than that of an LCD screen. Thus the Nixie display has come to have a fairly devoted niche following among electronics enthusiasts. Although the sturdier, cheaper LCD display replaced the Nixie in technical and consumer products decades ago, hobbyists can still obtain unused Nixie tubes to use in their own DIY projects. Handmade Nixie clocks in particular have become beloved conversation pieces for many design-conscious electronics aficionados.
Daylight Savings Time begins this Sunday. Don’t forget your clocks!