Not a quiz item but an old reminiscence is the subject of a BBC News article, the disappearing Solari Board departures indicator

https://www.bbc.co.uk/news/world-asia-51470599

They were one of those things that fascinated the public, as they clatter round from one display to the next. The noise of them, especially if they are doing a complete restart that happened occasionally was notable, and would get everyone's attention to see what was going to come up.

There were two variants, airports liked the format with individual letters making up names and numbers, but there were also full flaps, which were commonly used to put up the name and coloured logo of the airline. At train stations in Britain and Europe this full word format was more common, with the various station names all running round.

Few however understood the complexity behind the scenes. They were real mechanical marvels, with innumerable bicycle-chain links behind the board connecting them to various electric motors. To minimise the number of motors required there were some clever sequencing devices and clutches connecting multiple windows to one motor. In fact, behind the scenes was fascinating, with walkways for the maintenance mechanic to get at all the parts, change the flaps, deal with jams and breakages, and otherwise maintain the mechanical side, all typically strewn with lubricating oil residue thrown off by the machinery. Apparently a competent Solari mechanic could name their own salary.

It needed a competent operator as well, working with punched cards (technology of the times) which were prepared and then inserted into the operating console, pull a handle and it would send electrical impulses to all the various bicycle-chain drives. The operator could prepare special or replacement punched cards on a typewriter-like device.

Solari, the manufacturer from Italy, no longer make them, but there are dealers who buy up old ones being replaced, and break them up to provide secondhand spares for those that remain.

I particularly like the one shown at the end of the BBC article in the TWA terminal at JFK, surrounded by a splendid piece of space-age artwork which must surely be by the hand of terminal overall designer Mr Eero Saarinen himself. Did Jet Blue keep it when they modernised the terminal ?