System and method for supressing pulse dialing feedback occurring particularly with auxiliary acoustic ringers in socket telephone systems
US5818923A · kind A · utility
43Cited by
16References
51Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jul 19, 1996 |
| Grant date | Oct 6, 1998 |
| Priority date | — |
| Expiry date | Jul 19, 2016 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04M1/74
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
An acoustic feedback suppression system, particularly for auxiliary ringers in socket telephone systems, comprising a first terminal and a second terminal of a telephone line, an internal ringer, and an auxiliary ringer that is connected between the first and second telephone lines. The system comprises an activation circuit adapted to activate first and second switching circuits to reduce the voltage at the terminals of the auxiliary ringer, the activation circuit being controlled by an activation signal generated by a control and signaling circuit when a user dials a telephone number.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.