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US1689660A
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Method and arrangement for comparative alternating-current measurements
Assignee: Siemens and Halske AG
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Filing: 1925-01-29
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Granted: 1928-10-30
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Expires: 1945-01-29
Abstract
No abstract record available.
Inventors
- 👤 Albrecht Dieter
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 21:47
CPC Classifications
G; G01; G01R; G01R1/00; G01R1/28
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) | 1931-10-30 | 1932-04-30 | 1932-10-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1935-10-30 | 1936-04-30 | 1936-10-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1939-10-30 | 1940-04-30 | 1940-10-30 | $7700.00 | Window Closed / Lapsed |