US3274610A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Information recording circuit
Assignee: AT&T Inc
•
Filing: 1963-03-21
•
Granted: 1966-09-20
•
Expires: 1983-03-21
Abstract
No abstract record available.
Inventors
- 👤 Cyrus F Ault
- 👤 Friedman David
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 09:02
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/02; G11B5/09
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
54 words
A MAGNETIC RECORDING CIRCUIT FOR SELECTIVELY MAGNETIZING AND DEMAGNETIZING DISCRETE PORTIONS OF A MAGNETIC MEDIUM, COMPRISING A TRANSDUCER HAVING A SINGLE WINDING, MEANS FOR APPLYING ALTERNATING CURRENT TO SAID WINDING, MEANS SELECTIVELY OPERABLE FOR PROVIDING A DIRECTCURRENT SIGNAL TO SAID WINDING COINCIDENT WITH A CURRENT PEAK OF SAID ALTERNATING CURRENT AND FOR THEREAFTER DAMP-
References Cited (Backward Citations)
US2922144A
Cited
US3038036A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1969-09-19 | 1970-03-21 | 1970-09-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1973-09-19 | 1974-03-21 | 1974-09-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1977-09-19 | 1978-03-21 | 1978-09-20 | $7700.00 | Window Closed / Lapsed |