US2806757A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Multiple-channel magnetic recorder
Assignee: E R CHILCOTT
•
Filing: 1952-06-06
•
Granted: 1957-09-17
•
Expires: 1972-06-06
Abstract
No abstract record available.
Inventors
- 👤 James M Cunningham
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 13:42
CPC Classifications
G; G01; G01V; G01V1/00; G01V1/24; G11; G11B; G11B5/00; G11B5/004
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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US2698359A
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US2513409A
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US2505300A
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US2607654A
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US2615780A
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US2679551A
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US2644856A
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US2680785A
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US2685492A
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US2668879A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1960-09-16 | 1961-03-18 | 1961-09-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1964-09-16 | 1965-03-18 | 1965-09-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1968-09-16 | 1969-03-18 | 1969-09-17 | $7700.00 | Window Closed / Lapsed |