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In the movie Fantozzi va in pensione (1988) I see a strange cable for terminal connection, what kind of connection is this?

enter image description here

seems a scsi cable, but I know the terminal is Ampex 220 and as I know terminals use serial connection to communicate with central units.

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  • It's a film set so there's no need for the terminals to actually work. (We can't see the screens.) The ribbon cables may be no longer than is required to disappear out of shot. It would be quick and simple for the props department to make up short ribbon cables with insulation displacement connectors. The film is a comedy so there won't be any unnecessary effort spent on set dressing.
    – Graham Nye
    Jun 3, 2023 at 19:45

2 Answers 2

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It's probably much like the Ampex 210. See page 2-7 of the Ampex 210 Operating Manual. Based on the position, it would be the primary RS232S port connected to a ribbon cable.

Ribbon cables were used because they were cheap, but not very robust in an exposed environment where they would be subject to abuse.

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  • That's the main point. They were cheap and easy to configure with variable length (which again saved money by not wasting cable) . So win win in such a setup.
    – Raffzahn
    May 31, 2023 at 10:04
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    @Raffzahn while I broadly agree, I've definitely never seen them used in a "professional" situation, i.e. when setting up a business-critical mainframe etc.: at the very least I'd expect a braided sleeve (flat or cylindrical) over the ribbon. I did /once/ see somebody demoing an early word processor (size of a desk) with exposed ribbon cables to the printer etc., and they were fairly rapidly shown the door. Jun 1, 2023 at 7:39
  • @MarkMorganLloyd: Ribbon cables strike me as fine for situations involving limited kinds of movement. If the printer was intended for use in a drawer, a well secured ribbon would probably flex more smoothly and consistently, without ever binding, than a "round" cable.
    – supercat
    Jun 1, 2023 at 18:04
  • @supercat While adequate for things like lab bench work, in practice they were only used outside a screened (and physically protected) enclosure if they had a shield and sheath applied: they were quite simply too electrically and physically fragile. Believe me, I've seen far tougher cables wrecked by a user who either didn't appreciate their fragility or quite simply didn't give a damn (terminals covered by maintenance agreement etc.). Jun 4, 2023 at 7:57
  • @MarkMorganLloyd: The Apple II external floppy drives were routinely connected via ribbon cables, much like the ribbon cables used with floppy drives except that they had fewer connections, and carried power over the same ribbon as everything else, and that was simply how things were done.
    – supercat
    Jun 5, 2023 at 6:07
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25-wire ribbon cables were quite common for serial ports. See, for example, the classic breakout box:

serial breakout box

I preferred using cables and adapters. Typically I would use 6-wire cables (ground, TX, RX, CTS, RTS, possibly one more pin) and modular DB-25 (and later DB-9) adapters. But ribbon cables could work quite well if your connections were straight DTE (terminal) to DCE (modem or, in a room full of terminals, some sort of concentrator or multiplexer or I/O box) because you didn't have to swap wires around (you could with ribbon cable, like the IBM PC floppy cable twist, but it was a pain). Easy enough to attach to connectors once you get the hang of it. You could get a big roll of ribbon cable and cut off pieces to fit the actual distance needed and wire up a room like this pretty quickly.

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  • Thanks I never see ribbon cables for serial.
    – elbarna
    May 31, 2023 at 10:50
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    @elbarna Ribbon cables for serial devices were very common in the 70s/80s. Probably easier to manufacture (stretch 25 strands of single core copper in a line and cover in plastic), and easy to hand solder (machines to do this were more expensive than people). Even in recent times (up to 2010s), internally in a PC you would see cables for hard drives using 40 pin flat cables (PATA), before the days of SATA and USB.
    – Neil
    May 31, 2023 at 15:48
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    @Neil If you just wanted a straight through cable, there was no need to solder. D-Sub connectors were (and still are) available with IDC termination. May 31, 2023 at 17:59
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    What @PeterGreen said. The advantage of using ribbon was the ability to clamp on a D-Sub with nothing but a pair of pliers. Not a great cable, but super easy out in the field.
    – UncleCarl
    Jun 1, 2023 at 16:44
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    @UncleCarl, I made one with a coffee cup. I had the connector and the ribbon and absolutely no tools, so I just lined it up, held in on the concrete floor and used the empty coffee cup to tap tap tap it together. Worked fine. I've done 50 pin SCSI the same way. Necessity is the mother of invention. Plus, it's fun to brag about making a data cable with a coffee cup. :-)
    – Geo...
    Jun 1, 2023 at 18:59

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