US2494451A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Personal call system
Assignee: RCA Corp
•
Filing: 1946-01-31
•
Granted: 1950-01-10
•
Expires: 1966-01-31
Abstract
No abstract record available.
Inventors
- 👤 Harry F Olson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 20:00
CPC Classifications
H; H04; H04B; H04B5/00; H04M; H04M1/00; H04M1/26
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US388091A
Cited
US887357A
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US1689121A
Cited
US1797696A
Cited
GB323184A
Cited
US1955558A
Cited
US2122145A
Cited
US2138894A
Cited
GB495171A
Cited
US2293166A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1953-01-09 | 1953-07-11 | 1954-01-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1957-01-09 | 1957-07-11 | 1958-01-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1961-01-09 | 1961-07-11 | 1962-01-10 | $7700.00 | Window Closed / Lapsed |