Test system for detecting
US5636202A · kind A · utility
22Cited by
8References
19Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Jul 25, 1995 |
| Grant date | Jun 3, 1997 |
| Priority date | — |
| Expiry date | Jul 25, 2015 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04Q11/045
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
The invention is a test method for testing ISDN interfaces from a remote location. The test method of the invention applies predetermined energy signals to the tip and ring leads of the customer subscriber line in a prescribed sequence, delays 10 to 100 ms, and then makes measurements of the voltage across the tip and ring leads. The voltage measurements are compared to limit values identified from the NT1-U dc characteristic curve to determine pass/fail of the tested interface.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.