FIG. 1 shows the wiring configuration for a prior-art telephone system 10 for a residence or other building, wired with a telephone line 5, Residence telephone line 5 consists of single wire pair which connects to a junction-box 16, which in turn connects to a Public Switched Telephone Network (PSTN) 18 via a cable 17, terminating in a public switch 19, apparatus which establishes and enables tele