Test device for telephone lines
US6330306A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Aug 23, 1999 |
| Grant date | Dec 11, 2001 |
| Priority date | — |
| Expiry date | Aug 23, 2019 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04M3/2209
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
An in-line data protector for preventing a test set from accessing a telephone line under a predetermined condition is disclosed. The in-line data protector selectively connects the test set and the telephone line responsive to detection of a data signal on the telephone line. The in-line data protector includes a power circuit for providing general operating power, a processor connected to the telephone line, and a relay serially connected between the telephone line and the test set. When general operating power is received, the processor analyzes the telephone line by emulating a single band filter. By using a single band filter, a very good determination can be made as to whether a signal on the telephone line is a data signal or a voice signal. If the signal is not a data signal, the processor instructs the relay to close, thereby connecting the telephone line to the test set.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.