Patent US2720557A successfully refreshed from Google Patents.
US2720557A
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Time division pulse code modulation system employing continuous coding tube
Assignee: AT&T Inc
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Filing: 1948-12-24
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Granted: 1955-10-11
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Expires: 1968-12-24
Abstract
No abstract record available.
Inventors
- 👤 William M Goodall
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 22:53
CPC Classifications
H; H03; H03M; H03M1/00; H03M1/12; H03M1/14
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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US2412350A
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US2478919A
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US2418116A
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US2449467A
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US2451044A
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US2453461A
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US2453454A
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US2603714A
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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) | 1958-10-10 | 1959-04-11 | 1959-10-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1962-10-10 | 1963-04-11 | 1963-10-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1966-10-10 | 1967-04-11 | 1967-10-11 | $7700.00 | Window Closed / Lapsed |