Synchronous ring detector for station carrier telephone systems
US4081609A · kind A · utility
7Cited by
1References
4Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jan 28, 1977 |
| Grant date | Mar 28, 1978 |
| Priority date | — |
| Expiry date | Jan 28, 1997 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04M19/04
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A plural channel amplitude modulated station carrier signalling circuit in which an incoming call for a subscriber served by the station carrier system is sensed at the called subscriber's subscriber channel terminal circuit by synchronously detecting a signal which originates from a central office to signal the incoming call for the subscriber.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.