Patent US2656408A successfully refreshed from Google Patents.
US2656408A
Expired / Lapsed
US
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Subscriber signaling system
Assignee: Zenith Electronics LLC
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Filing: 1949-05-21
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Granted: 1953-10-20
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Expires: 1969-05-21
Abstract
No abstract record available.
Inventors
- 👤 Richard O Gray
- 👤 Erwin M Roschke
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 01:39
CPC Classifications
H; H04; H04N; H04N7/00; H04N7/16; H04N7/162; H04N7/165; H04N7/167; H04N7/169; H04N7/1693
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1310719A
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US1356546A
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GB386849A
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US2237533A
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US2251525A
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US2403059A
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US2402067A
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US2405252A
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US2403540A
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US2414101A
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US2472774A
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US2510046A
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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 |