In spy movies, there are often sequences showing an overview of the ocean or a city, with a location like "SOUTH PACIFIC SEA" being written, letter by letter (often uppercase / fixed width / green / segment-based) on the screen, with a tiny, morse-like, digital sound being played for each letter.
Examples:
- The Brothers Grimsby (03:30) -- digital sound, very close to the one I'm mainly thinking about
- The Dictator (04:50) -- a more mechanical sound
- Terminator 1/2 (whenever Arnold "scans" the room) -- a more complex, combined sound
Does this sound effect originate from some kind of historical intelligence apparatus, like a telex machine, a teleprompter, etc.? Or is it purely a Hollywood invention that is repeated by convention.
YouTube has some examples, becomingly called digital/military text typing.