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Patent US2821686A successfully refreshed from Google Patents.
US2821686A
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Mechanical filters including rejectors
Assignee: RCA Corp
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Filing: 1955-07-15
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Granted: 1958-01-28
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Expires: 1975-07-15
Abstract
No abstract record available.
Inventors
- 👤 Jr Leslie L Burns
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 11:44
CPC Classifications
H; H03; H03H; H03H9/00; H03H9/46; H03H9/48; H03H9/50
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) | 1961-01-27 | 1961-07-29 | 1962-01-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-01-27 | 1965-07-29 | 1966-01-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-01-27 | 1969-07-29 | 1970-01-28 | $7700.00 | Window Closed / Lapsed |