Remotely actuated telephone instrument connection block having instrument lockout feature
US4434328A · kind A · utility
14Cited by
3References
14Claims
0Family size
Inventor
Key dates
| Filing date | Jun 21, 1982 |
| Grant date | Feb 28, 1984 |
| Priority date | — |
| Expiry date | Jun 21, 2002 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04M3/301
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A lockout circuit improves a remotely activated loop testing connection block for disconnecting a telephone subscriber's service instrument from a telephone tip and ring line pair during a test interval. The lockout circuit includes a latching relay which is responsive to a lockout command signal only when it is sent during a remotely commanded test interval. The instrument is reconnected automatically at the beginning of a subsequent test interval.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.