Patent US4280391A successfully refreshed from Google Patents.
US2615971A
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US
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Pulse position dial receiver employing pulse superposition for identifying digits
Assignee: AT&T Inc
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Filing: 1948-12-30
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Granted: 1952-10-28
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Expires: 1968-12-30
Abstract
No abstract record available.
Inventors
- 👤 William A Malthaner
- 👤 Neal D Newby
- 👤 Henry E Vaughan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 16:51
CPC Classifications
H; H04; H04Q; H04Q1/00; H04Q1/18; H04Q1/30; H04Q1/40
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1952369A
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US2403561A
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US2403009A
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US2407336A
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US2415359A
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US2449819A
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US2443198A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1955-10-28 | 1956-04-28 | 1956-10-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1959-10-28 | 1960-04-28 | 1960-10-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1963-10-28 | 1964-04-28 | 1964-10-28 | $7700.00 | Window Closed / Lapsed |