Patent US1872940A successfully refreshed from Google Patents.
US1872940A
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US
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Relay receiving circuit for carrier telegraph signals
Assignee: International Communications Laboratories Inc
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Filing: 1930-07-01
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Granted: 1932-08-23
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Expires: 1950-07-01
Abstract
No abstract record available.
Inventors
- 👤 Frederick G Hallden
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 07:55
CPC Classifications
H; H04; H04L; H04L25/00; H04L25/02; H04L25/0264; H04L25/0292; H04L25/0266; H04L25/027; H04L25/12; H04L25/0272
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1935-08-23 | 1936-02-22 | 1936-08-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1939-08-23 | 1940-02-22 | 1940-08-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1943-08-23 | 1944-02-22 | 1944-08-23 | $7700.00 | Window Closed / Lapsed |