US3361878A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Signal switching system utilizing magnetic switching for rotating head recorders
Assignee: Ampex Corp
•
Filing: 1964-03-11
•
Granted: 1968-01-02
•
Expires: 1984-03-11
Abstract
No abstract record available.
Inventors
- 👤 Donald M Patterson
- 👤 Robert L Davis
- 👤 Robert F Pfost
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 05:26
CPC Classifications
G; G11; G11B; G11B15/00; G11B15/02; G11B15/12; G11B15/14
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2401175A
Cited
US1302284A
Cited
US2740110A
Cited
US3081381A
Cited
GB865168A
Cited
US3152226A
Cited
US3229035A
Cited
US3170031A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1971-01-01 | 1971-07-03 | 1972-01-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1975-01-01 | 1975-07-03 | 1976-01-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1979-01-01 | 1979-07-03 | 1980-01-02 | $7700.00 | Window Closed / Lapsed |