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geekhack Community => Keyboards => Topic started by: lee+ on Sat, 18 June 2016, 13:18:32
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Hi,
what's the maximum length a keyboard cable can have, for keyboards with PS/2 and DIN connectors? Is there a specification stating a maximum length?
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These folks estimate 50 meters.
http://www.pcmech.com/article/how-far-can-that-wire-go/
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Thanks!
50m is a bit optimistic as an estimate, IMHO. IIRC, parallel printer cables are specified for max. 20m, and they use 12V signals.
In any case, I'll probably be more limited by the max. length of the display port cable.
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Longest one I have is a 3 metre SDL cable for a model M, although it's coiled so it stretches comfortably beyond that.
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depending on what kind of display port you are using...
search for "KVM cable"
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coiled is so bad though. snags on everything, and most of them are too stiff anyway. terrible!
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eugh - who wants to have to carry their cable in a wheelbarrow?
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Also kinda depends on the quality of the cable and if it is in one piece or with some extensions. Cheap extension cables tend to have problems after 6-10m, good quality one-piece cables can be much longer.
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depending on what kind of display port you are using...
search for "KVM cable"
That's display port 1.2 --- only the 3rd cable I got finally worked.
I guess once we get 8k displays, we'll need optical cables because the transfer rates will be too high for copper ones. It would already make sense with 4k.
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coiled is so bad though. snags on everything, and most of them are too stiff anyway. terrible!
Tell me about it.
But then, I'm considering getting a coiled one as it would fit so well to two of my keyboards. It would be just right somehow, and I don't need to carry it around.
Also, they're probably cheap because nobody in their right mind would want one ;)
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coiled is so bad though. snags on everything, and most of them are too stiff anyway. terrible!
Tell me about it.
But then, I'm considering getting a coiled one as it would fit so well to two of my keyboards. It would be just right somehow, and I don't need to carry it around.
Also, they're probably cheap because nobody in their right mind would want one ;)
if you say you have a good reason, i will allow it
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coiled is so bad though. snags on everything, and most of them are too stiff anyway. terrible!
Tell me about it.
But then, I'm considering getting a coiled one as it would fit so well to two of my keyboards. It would be just right somehow, and I don't need to carry it around.
Also, they're probably cheap because nobody in their right mind would want one ;)
if you say you have a good reason, i will allow it
You're so generous :)
I made up my mind, I do want a coiled one. There's a lot to be said for a coiled cable, like it would simply be too short if it wasn't coiled.
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Hi,
what's the maximum length a keyboard cable can have, for keyboards with PS/2 and DIN connectors? Is there a specification stating a maximum length?
Depends on the resistance (and thus purity) of the cable material. Theoretically, an electrical signal can propagate infinitely, given a zero-impedance medium, but such a medium hasn't yet been discovered.
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Hi,
what's the maximum length a keyboard cable can have, for keyboards with PS/2 and DIN connectors? Is there a specification stating a maximum length?
Depends on the resistance (and thus purity) of the cable material. Theoretically, an electrical signal can propagate infinitely, given a zero-impedance medium, but such a medium hasn't yet been discovered.
At some point it would take too long for the signals to travel from the keyboard to the computer, and you would feel as if you were using an USB keyboard.