US2570221A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Pulse code modulation system
Assignee: International Standard Electric Corp
•
Filing: 1949-02-10
•
Granted: 1951-10-09
•
Expires: 1969-02-10
Abstract
No abstract record available.
Inventors
- 👤 Earp Charles William
- 👤 Wintle Malcolm Frank
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 23:46
CPC Classifications
H; H03; H03M; H03M1/00; H03M1/12; H03M1/34; H03M1/38; H03M1/44; H03M1/445
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2272070A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1954-10-08 | 1955-04-09 | 1955-10-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-10-08 | 1959-04-09 | 1959-10-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-10-08 | 1963-04-09 | 1963-10-09 | $7700.00 | Window Closed / Lapsed |