Electrical power and telephone ringer signal distribution system
US5682423A · kind A · utility
37Cited by
5References
6Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | May 28, 1996 |
| Grant date | Oct 28, 1997 |
| Priority date | — |
| Expiry date | May 28, 2016 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04M19/00
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A telephony system includes a plurality of local network terminations connected to a street cabinet in turn connected to an exchange. The street cabinet has a power supply for supplying voltage, a clock for generating a master ringer signal, and a modulator for modulating the voltage with the ringer signal. The filters extract the DC voltage and the ringer signal. The extracted DC voltage and the extracted ringer signal obviate the prior art requirements to provide a separate DC power supply and a separate clock within each local network termination, thereby avoiding duplication of components within each local network termination.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.