Busy-test arrangement for electronic private automatic branch exchange
US3963874A · kind A · utility
42Cited by
5References
15Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jan 22, 1975 |
| Grant date | Jun 15, 1976 |
| Priority date | — |
| Expiry date | Jan 22, 1995 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04Q3/521
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
In an electronic private automatic branch exchange telephone system, busy test is carried out by way of a two step process. Initially, a junctor memory is scanned and the called number is compared with each ING and ED number contained in memory. At the completion of the scan and comparison a check of the calling bridge relay of the called number is made. Associated with the busy test arrangement are camp-on and call-waiting features which may also be carried out during the test.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.