Telephone system allowing hold releasing request from central office line
US4852158A · kind A · utility
2Cited by
1References
9Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jan 27, 1988 |
| Grant date | Jul 25, 1989 |
| Priority date | — |
| Expiry date | Jan 27, 2008 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04Q3/627
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A telephone system which allows external releasing of a holding state set by a holding operation of a telephone set. A signal receiving circuit of the system receives a holding-state releasing signal such as a DTMF signal or the like sent from a central office line to release the hold state of the telephone set on the basis of an output of the circuit.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.