US2538266A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Communication system employing pulse code modulation
Assignee: AT&T Inc
•
Filing: 1945-05-10
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Granted: 1951-01-16
•
Expires: 1965-05-10
Abstract
No abstract record available.
Inventors
- 👤 John R Pierce
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 23:17
CPC Classifications
H; H04; H04B; H04B14/00; H04B14/02; H04B14/04; H04B14/046; H04B14/048; H03; H03M; H03M1/00; H03M1/12; H03M1/50; H03M1/504
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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US2146876A
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US2403561A
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US2416330A
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US2419340A
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1954-01-15 | 1954-07-17 | 1955-01-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-01-15 | 1958-07-17 | 1959-01-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-01-15 | 1962-07-17 | 1963-01-16 | $7700.00 | Window Closed / Lapsed |