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Patent US2656415A successfully refreshed from Google Patents.
US2656415A
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Tuning indicator for frequency shift telegraph systems
Assignee: British Telecommunications PLC
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Filing: 1951-08-13
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Granted: 1953-10-20
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Expires: 1971-08-13
Abstract
No abstract record available.
Inventors
- 👤 Terlecki Renat
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 23:00
CPC Classifications
H; H03; H03J; H03J3/00; H03J3/02; H03J3/12; H03J3/14; H04; H04L; H04L27/00; H04L27/10; H04L27/16
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1956-10-19 | 1957-04-20 | 1957-10-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1960-10-19 | 1961-04-20 | 1961-10-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1964-10-19 | 1965-04-20 | 1965-10-20 | $7700.00 | Window Closed / Lapsed |