We recently moved into a 1960's house. 4 of the bedrooms have dual RJ-45 and RJ-11 receptacles. When I got cable installed, they had to run a new wire from the telephone pole out front. I was told the coax in the house was really old and wasn't being used. I was also informed the previous owners must have had DSL.

Our network is working great with the new cable setup, but I wanted to make use of the Ethernet that has already been ran throughout our house (it is Cat 5e). I found out one of the Ethernet cables runs all the way to the garage, then out of the crawl space, up to this adapter thing. I just wanted to see if someone could shed some light on what might be going on here? What might this adapter be for?

  • That's definately not wired for ethernet that's for sure.
    – hookenz
    Nov 2, 2019 at 22:29
  • That makes sense. I'll retrace the wire and probably find it leads to one of the RJ-11s.
    – vim_usr
    Nov 3, 2019 at 1:14

2 Answers 2


This was your original BELL system wiring throughout your house. It would have been modified throughout the years as bell added new cable for the old DSL service. You can see the old service drop coming in from the top and the distribution phone lines branching out from there. Who are you with now? If you're not using any of that wiring for your existing service, you can use it for whatever you need. I know this is vague but so is the picture.


One of the twisted pair is being used for phone line and this "adapter" just splices 1 pair from the cat5e to the telephone wire.

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