US2901687A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and apparatus for ground-wave transmission and reception of radio waves
Assignee: ENGINEERING RES CORP
•
Filing: 1950-09-30
•
Granted: 1959-08-25
•
Expires: 1970-09-30
Abstract
No abstract record available.
Inventors
- 👤 William M Barret
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 20:28
CPC Classifications
H; H04; H04B; H04B13/00; H04B13/02
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1101914A
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1962-08-24 | 1963-02-23 | 1963-08-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1966-08-24 | 1967-02-23 | 1967-08-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1970-08-24 | 1971-02-23 | 1971-08-25 | $7700.00 | Window Closed / Lapsed |