US2438903A
Expired / Lapsed
US
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Pulse communication system employing pulse frequency reduction for signaling
Assignee: STC PLC
•
Filing: 1943-10-11
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Granted: 1948-04-06
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Expires: 1963-10-11
Abstract
No abstract record available.
Inventors
- 👤 Edmond M Deloraine
- 👤 Donald D Grieg
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 08:05
CPC Classifications
G; G08; G08C; G08C19/00; G08C19/16; G08C19/28; H; H04; H04J; H04J3/00; H04J3/02; H04J3/12; H04Q; H04Q1/00; H04Q1/18; H04Q1/30; H04Q1/44; H04Q1/442; H04Q1/4423
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1484405A
Cited
US1532336A
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US2048081A
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GB418525A
Cited
US2172354A
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US2204375A
Cited
US2213941A
Cited
US2263369A
Cited
US2326584A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1951-04-06 | 1951-10-06 | 1952-04-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1955-04-06 | 1955-10-06 | 1956-04-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1959-04-06 | 1959-10-06 | 1960-04-06 | $7700.00 | Window Closed / Lapsed |