Patent US2779822A successfully refreshed from Google Patents.
US2779822A
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US
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Communication switching system employing gas tubes
Assignee: AT&T Inc
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Filing: 1955-03-25
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Granted: 1957-01-29
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Expires: 1975-03-25
Abstract
No abstract record available.
Inventors
- 👤 Raymond W Ketchledge
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 19:47
CPC Classifications
H; H03; H03K; H03K17/00; H03K17/51; H03K17/52; H04; H04Q; H04Q3/00; H04Q3/42; H04Q3/52; H04Q3/525
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1960-01-29 | 1960-07-30 | 1961-01-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1964-01-29 | 1964-07-30 | 1965-01-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1968-01-29 | 1968-07-30 | 1969-01-29 | $7700.00 | Window Closed / Lapsed |