Patent US1937796A successfully refreshed from Google Patents.
US1937796A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Attenuating and selecting circuts
Assignee: International Communications Laboratories Inc
•
Filing: 1931-01-23
•
Granted: 1933-12-05
•
Expires: 1951-01-23
Abstract
No abstract record available.
Inventors
- 👤 Rothwell E Smith
- 👤 Leo A Kelley
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 14:50
CPC Classifications
H; H04; H04B; H04B3/00; H04B3/02; H04B3/04; H04B3/14; H04B3/141
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
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) | 1936-12-04 | 1937-06-05 | 1937-12-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1940-12-04 | 1941-06-05 | 1941-12-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1944-12-04 | 1945-06-05 | 1945-12-05 | $7700.00 | Window Closed / Lapsed |