US2662934A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Vacuum tube amplifier circuits for coded carrier current
Assignee: Westinghouse Air Brake Co
•
Filing: 1949-02-08
•
Granted: 1953-12-15
•
Expires: 1969-02-08
Abstract
No abstract record available.
Inventors
- 👤 Leslie R Allison
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 09:02
CPC Classifications
B; B61; B61L; B61L3/00; B61L3/16; B61L3/22; B61L3/221
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2515916A
Cited
US1243789A
Cited
US1759631A
Cited
US2293415A
Cited
US2336766A
Cited
US2541879A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1956-12-14 | 1957-06-15 | 1957-12-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1960-12-14 | 1961-06-15 | 1961-12-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1964-12-14 | 1965-06-15 | 1965-12-15 | $7700.00 | Window Closed / Lapsed |