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US2926344A
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Multiple frequency signalling method and system
Assignee: KOILED KORDS Inc
•
Filing: 1956-08-13
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Granted: 1960-02-23
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Expires: 1976-08-13
Abstract
No abstract record available.
Inventors
- 👤 Robert L Koehler
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 08:21
CPC Classifications
H; H04; H04M; H04M11/00; H04M11/04
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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US2137349A
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US2315383A
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US2510139A
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US2554329A
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US2604518A
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US2443125A
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US2558888A
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US2611031A
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US2729703A
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US2817025A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1963-02-22 | 1963-08-24 | 1964-02-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1967-02-22 | 1967-08-24 | 1968-02-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1971-02-22 | 1971-08-24 | 1972-02-23 | $7700.00 | Window Closed / Lapsed |