US2972128A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Phase modulated pulse recording systems
Assignee: Unisys Corp
•
Filing: 1956-07-30
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Granted: 1961-02-14
•
Expires: 1976-07-30
Abstract
No abstract record available.
Inventors
- 👤 Jr John Presper Eckert
- 👤 Jr John Clark Sims
- 👤 Welsh Herbert Frazer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 23:44
CPC Classifications
G; G11; G11B; G11B20/00; G11B20/10; G11B20/14; G11B20/1403; G11B20/1407; G11B20/1419
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2540654A
Cited
US2611813A
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US2702315A
Cited
US2718356A
Cited
US2721990A
Cited
US2700155A
Cited
US2782398A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1964-02-14 | 1964-08-15 | 1965-02-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1968-02-14 | 1968-08-15 | 1969-02-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1972-02-14 | 1972-08-15 | 1973-02-14 | $7700.00 | Window Closed / Lapsed |