Here the line 1 is on the inner pair of wires and line 2 is on the outer pair. A decent electrician or tech can wire this as you need. If this makes no sense at all, then you need to call in the electrician or tech to set it up.
We live in a fairly rural part of New York where the landlines survive storms better than the internet service, so we want to maintain a landline. However we are also paying for internet voice service thru the cable company because internet, TV and voice bundled is cheaper than any two by themselves. It would be helpful if we could have both services combined in a two-line phone.
We have an older 2-line phone (GE 2-9436B) that worked fine with two land-lines. They came to a coupler and the coupler was connected to the single input jack of the phone. (We gave up one of the landlines after my wife and I both retired.)
The cable company's voice also works fine when I connect the modem phone output to the phone's input.
I thought that if I bought a coupler I could connect the landline and cable to the side with two jacks and take the coupler output to the phone input, so I tried that. However when I do that I get no dial tone on either line.
Should that not work? Or is there something about the two technologies that makes them incompatible when employed in this way?
Any advice will be greatly appreciated.

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