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US1831744A
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Method and apparatus for measuring the amplification ratio of electric amplifiers
Assignee: Telefonaktiebolaget LM Ericsson AB
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Filing: 1929-03-30
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Granted: 1931-11-10
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Expires: 1949-03-30
Abstract
No abstract record available.
Inventors
- 👤 Laurent Torbern
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 10:30
CPC Classifications
H; H04; H04B; H04B1/00; H04B1/60
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) | 1934-11-09 | 1935-05-11 | 1935-11-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1938-11-09 | 1939-05-11 | 1939-11-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1942-11-09 | 1943-05-11 | 1943-11-10 | $7700.00 | Window Closed / Lapsed |