US1647609A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Heterodyne receiving system
Assignee: FED TELEPHONE Manufacturing CORP
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Filing: 1925-02-16
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Granted: 1927-11-01
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Expires: 1945-02-16
Abstract
No abstract record available.
Inventors
- 👤 William F Cotter
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 20:45
CPC Classifications
H; H04; H04B; H04B1/00; H04B1/06; H04B1/16; H04B1/26
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) | 1930-10-31 | 1931-05-02 | 1931-11-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1934-10-31 | 1935-05-02 | 1935-11-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1938-10-31 | 1939-05-02 | 1939-11-01 | $7700.00 | Window Closed / Lapsed |