US2590672A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Carrier system having variable power level for supervisory signaling
Assignee: Automatic Electric Laboratories Inc
•
Filing: 1950-06-29
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Granted: 1952-03-25
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Expires: 1970-06-29
Abstract
No abstract record available.
Inventors
- 👤 Bakker Pier
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 22:39
CPC Classifications
H; H04; H04Q; H04Q3/00; H04Q3/0016
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1572756A
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US1589405A
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US1688455A
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US1984066A
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US2155176A
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US2345048A
Cited
US2523914A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1955-03-25 | 1955-09-24 | 1956-03-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1959-03-25 | 1959-09-24 | 1960-03-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1963-03-25 | 1963-09-24 | 1964-03-25 | $7700.00 | Window Closed / Lapsed |