Telephone ring signal detector
US5920624A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jun 16, 1997 |
| Grant date | Jul 6, 1999 |
| Priority date | — |
| Expiry date | Jun 16, 2017 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04M1/654
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A telephone ring signal detector for detecting a telephone ring signal voltage on a telecommunications line connectable to at least one line telephone device. Detector includes a ring signal processor comprising a voltage translating device for providing a translated electrical parameter and an electrical parameter threshold setting device for providing a predetermined threshold reference electrical parameter value. The setting device provides a ring signal detect output signal when an electrical parameter value of the translated parameter exceeds the predetermined threshold reference electrical parameter value in a first quarter cycle time period of a first telephone ring signal cycle time period. In response to the ring signal detect output signal, a line impedance switch couples a first telephone device off-hook terminal impedance to the line to provide a first answering function, couples a detector line signal to the line and provides a simulated telephone ring signal to a telephone device output port connectable to an output telephone device. The output telephone device terminal impedance is monitored by an output line monitor to activate or deactivate a port coupling line swi…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.