We’ve recently noticed an uptick of interest in so-called “bubble displays”: vintage alphanumeric LEDs which are probably best remembered as being used in watches and calculators before the LCD took ...

For those of us who remember LED calculators, the HP 5082-7400 series red “bubble” displays hold a special charm. Available in 3, 4, or 5-digit varieties, these multiplexed 7-segment displays provided ...