Patent Explorer
Browse, filter, and analyze 2 patents across global jurisdictions.
| Patent Number | Title | Assignee | Status | Filing Date | Grant Date | Expires | Remaining | Claims | Actions |
|---|---|---|---|---|---|---|---|---|---|
| US4058678A | Remote signalling to a telephone line utilizing power line carrier signals | Astech Inc | Expired / Lapsed | 1976-04-07 | 1977-11-15 | 1996-04-07 | 0.0 yrs | 10 | |
| US3949172A | Telephone extension system utilizing power line carrier signals | Astech Inc | Expired / Lapsed | 1974-02-08 | 1976-04-06 | 1994-02-08 | 0.0 yrs | 22 |