US2621289A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Frequency changing system
Assignee: RCA Corp
•
Filing: 1949-04-19
•
Granted: 1952-12-09
•
Expires: 1969-04-19
Abstract
No abstract record available.
Inventors
- 👤 George W Gray
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 13:47
CPC Classifications
H; H04; H04B; H04B1/00; H04B1/06; H04B1/16; H04B1/26
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2277000A
Cited
US2361437A
Cited
US2266670A
Cited
US2477585A
Cited
US2480599A
Cited
US2445161A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1955-12-09 | 1956-06-09 | 1956-12-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1959-12-09 | 1960-06-09 | 1960-12-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1963-12-09 | 1964-06-09 | 1964-12-09 | $7700.00 | Window Closed / Lapsed |