US2418928A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Telegraph system and apparatus for selective single or double channel operation
Assignee: AT&T Teletype Corp
•
Filing: 1944-11-04
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Granted: 1947-04-15
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Expires: 1964-11-04
Abstract
No abstract record available.
Inventors
- 👤 Wilbur R Gemmel
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 21:32
CPC Classifications
H; H04; H04L; H04L5/00; H04L5/22; H04L5/24
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2231375A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1950-04-14 | 1950-10-14 | 1951-04-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1954-04-14 | 1954-10-14 | 1955-04-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1958-04-14 | 1958-10-14 | 1959-04-15 | $7700.00 | Window Closed / Lapsed |