System for testing 2B1Q telephony loopback circuits and method therefor
US5140625A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 4, 1991 |
| Grant date | Aug 18, 1992 |
| Priority date | — |
| Expiry date | Mar 4, 2011 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04M3/244
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A system for testing 2B1Q private line data telephony circuits having 2B1Q modulation between the network channel termination equipment and the channel unit. 2B1Q modulation is provided over a single pair of wires connected to the E and M leads of the channel unit. The system can deliver testing signals from two different sources. The first source is from a remote testing system connected to a remote access system which in turn is connected to the T, T1, R, and R1 output leads of the channel unit. The remote testing system generates conventional testing signals which are converted into digital signals for directly communicating with the 2B1Q pair of wires. The remote testing system delivers conventional tests for testing the loopback of the channel connected to the single pair of wires and to the network channel termination equipment. Under a second source of tests, the interface of the present invention directly connects to the T1 carrier. Testing digital signals are delivered from a distant source into the interface which are then delivered to the 2B1Q channel between the channel unit and the network channel termination equipment for performing loopback testing of the private lin…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.