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US2192959A
Expired / Lapsed
US
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Tone control system
Assignee: RCA Corp
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Filing: 1937-04-30
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Granted: 1940-03-12
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Expires: 1957-04-30
Abstract
No abstract record available.
Inventors
- 👤 Randall C Ballard
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 12:19
CPC Classifications
H; H03; H03G; H03G5/00; H03G5/02; H03G5/04; H03G5/06
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1943-03-12 | 1943-09-11 | 1944-03-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1947-03-12 | 1947-09-11 | 1948-03-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1951-03-12 | 1951-09-11 | 1952-03-12 | $7700.00 | Window Closed / Lapsed |