Patent US2616971A successfully refreshed from Google Patents.
US2616971A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Automatic volume control
Assignee: AT&T Inc
•
Filing: 1949-03-05
•
Granted: 1952-11-04
•
Expires: 1969-03-05
Abstract
No abstract record available.
Inventors
- 👤 Walter F Kannenberg
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 05:47
CPC Classifications
H; H04; H04M; H04M1/00; H04M1/60; H04M1/6033; H03; H03G; H03G3/00; H03G3/20; H03G3/22; H03G3/24
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
US1356403A
Cited
US2338551A
Cited
US2382848A
Cited
US2420933A
Cited
US2392218A
Cited
US2501327A
Cited
US2462532A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1955-11-04 | 1956-05-05 | 1956-11-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1959-11-04 | 1960-05-05 | 1960-11-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1963-11-04 | 1964-05-05 | 1964-11-04 | $7700.00 | Window Closed / Lapsed |