Does this make sense to you?

[Robert.Thompson]

Hello:

My friend just purchased a house but did not connect a phone service as he only uses his cell phone. The house is fully wired for telephones.

Yesterday, I took my spare OBI 110 over and hooked it up to his high speed cable modem. We then plugged a wire into the OBI's 'Phone' port and plugged the other end of it into a wall jack.

He can connect a phone to any wall jack in his house and dial out through the OBI. (He has 4 connected now)

Is that normal?

[CoalMinerRetired]

Yes, it makes sense and the phone port on the Obi is intended to work that way. The port produces enough power to make five 'ringer equivalents.'

See this write up for a full and complete explanation: The Original How to Distribute VoIP Throughout a Home.  Note the warning in there:

UNDER NO CIRCUMSTANCES should you connect your VoIP adapter to your inside wiring until you have completely read AND FOLLOWED the instructions in the following paragraphs. We are amazed that we still receive e-mails from people who have clearly NOT followed these instructions, have more than likely damaged or destroyed their VoIP adapters, and then still ..... After you've destroyed your VoIP adapter there isn't a single thing we can do to help you, so PLEASE read the following paragraphs carefully and if you do not COMPLETELY understand what needs to be done, do not proceed!

What they are warning is make sure you have already isloated the phone wiring in your house from the PSTN/Telco Central Office.

[Rick]

What they are warning is make sure you have already isloated the phone wiring in your house from the PSTN/Telco Central Office.

In other words, even though your friend has no POTS service, they should ensure that if there is a phone wire coming into the house from outside, that they remove those wires from connection to the internal wiring.