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I am interested to know if that if two network cables are to be joined together,can we use a pair of rj-45 to connect them?

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up vote 5 down vote accepted


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Just make sure you get a straight-through coupler, otherwise it will modify the pinout. – MaQleod Oct 29 '10 at 21:15
And is there a decrease in the speed? – Fahad Uddin Oct 29 '10 at 21:16
@fahad: No, there won't be. – Billy ONeal Oct 29 '10 at 21:24
You should be fine so long as the total length is within specifications for cat5 (or whatever you are using.) – Chris Nava Oct 29 '10 at 22:09
I have several RJ-45 couplers fitted at work with no problems at all. Saves relaying long runs of cable when a cabinet is moved. You can pay a premium price at places like BlackBox or buy a cheapie at somewhere like Novatech. – Tog Oct 30 '10 at 6:55

Two RJ-45s can't be connected together. They're both "male" connectors.

Something like this product ( would work. Unfortunately, it's not much cheaper than just buying a longer patch cable. (I have no affiliation with Newegg.)

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Can't we just join the wires together?I have seen that it works.With a decrease in speed? – Fahad Uddin Oct 29 '10 at 21:13
@fahad: It would be difficult to do it just by splicing the wires -- the wires themselves need to be the exact same length, and you can't untwist the wires in the cable or you will put it out of spec -- the twisted nature of the cable is one of the ways external interference is handled in-cable. You would also need to ensure that there was not large blobs of metal or soldier hanging off the cables, as that would increase the capacitance and inductance of the cable, which would (again) put it out of spec. – Billy ONeal Oct 29 '10 at 21:27
But ultimately it would probably work, in a pinch. Better, use a coupler - they're about GBP £0.50. Best, replace the cable. – tomfanning Dec 3 '12 at 16:09

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