Patent US1657462A successfully refreshed from Google Patents.
US1657462A
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US
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Nonsinging reamplifying circuits
Assignee: AT&T Inc
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Filing: 1923-05-15
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Granted: 1928-01-31
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Expires: 1943-05-15
Abstract
No abstract record available.
Inventors
- 👤 Espenschied Lloyd
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 11:23
CPC Classifications
H; H03; H03F; H03F3/00; H03F3/46; H03F3/48; F; F23; F23L; F23L7/00; F23L7/002; F23L7/005; H03B; H03B19/00; H03B19/06; H03B19/08; H03B19/10
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) | 1931-01-30 | 1931-08-01 | 1932-01-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1935-01-30 | 1935-08-01 | 1936-01-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1939-01-30 | 1939-08-01 | 1940-01-31 | $7700.00 | Window Closed / Lapsed |