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Wiring Connection Help

Wiring Connection Help

Wiring Connection Help


We just moved into a home which has been prewired with RJ45 jacks for computer and telephone connections. Our cable modem / router / phone device is in family room and the desktop computer is in the study (it does not have a wifi card). There is 1 RJ45 connection for modem / router / phone device in the family room. With that as the basis here is the question.

If I understand the RJ45 cabling correctly, the two phone wires are not used for a computer set up. So wires / cables, can you use one cable and split it for both phone connection and computer connection. The reason I ask is that I want to use the computer connection wires between the family room and the study for the desktop and the phone connection to provide phone service to the rest of the house. Basically, is there a splitter I can buy or do I have to make my own? Also is there any issues with these two services in the same cable?

I hope I have explained this clearly enough, if not please reply with questions.

Thanks in advance for your help!

RE: Wiring Connection Help

Typically in the UK anyway however I imagine this will apply elsewhere. the phone will be on pins 4&5 on the RJ45 (the blue pair), if your switch/router is running at 100mb/s it will only be using 2 pairs, pins 1&2 and 3&6 (oranges and greens)
So yes you can have a splitter


Calum M

RE: Wiring Connection Help

Running voice & data on the same cable isn't recommended. Could a cordless telephone with multiple handsets be, somehow, utilized?

I love2 "FEATURE 00"

RE: Wiring Connection Help

Thank you both for your comments. Now I have to go to work on the issue.

RE: Wiring Connection Help

Sounds like the answer is in the previous responses. Unless you are using POE(Power over Ethernet) or Gigabit from your switch, you should be able to use 7 & 8 for an analog phone (Brown/White and Brown).
Purchase a wall jack with your RJ45 and RJ11 combined and it should be fine.

RE: Wiring Connection Help

yes you can run voice and data on one cable if that's all you have, two cables would be better .
ISDN intigrated systems digital network

Google search "smart jack"

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