Patent US2542991A successfully refreshed from Google Patents.
US2542991A
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US
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Pulse modulation communication system
Assignee: International Standard Electric Corp
•
Filing: 1945-05-21
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Granted: 1951-02-27
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Expires: 1965-05-21
Abstract
No abstract record available.
Inventors
- 👤 Chatterjea Prafulla Kumar
- 👤 Scully Charles Thomas
- 👤 Ambrose Dermot Min
- 👤 Beney James Kinloch
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 17:12
CPC Classifications
H; H04; H04J; H04J3/00; H04J3/02; H04J3/06; H04J3/0602; H04J3/0614
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2172746A
Cited
US2262838A
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US2263369A
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US2282046A
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US2277000A
Cited
US2403210A
Cited
US2395467A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1954-02-26 | 1954-08-28 | 1955-02-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-02-26 | 1958-08-28 | 1959-02-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-02-26 | 1962-08-28 | 1963-02-27 | $7700.00 | Window Closed / Lapsed |