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US1607668A
Expired / Lapsed
US
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Carrier transmission over power circuits
Assignee: AT&T Inc
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Filing: 1924-04-29
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Granted: 1926-11-23
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Expires: 1944-04-29
Abstract
No abstract record available.
Inventors
- 👤 Charles H Fetter
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 23:33
CPC Classifications
H; H04; H04B; H04B3/00; H04B3/54; H04B3/56
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) | 1929-11-22 | 1930-05-24 | 1930-11-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1933-11-22 | 1934-05-24 | 1934-11-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1937-11-22 | 1938-05-24 | 1938-11-23 | $7700.00 | Window Closed / Lapsed |