Patent US3356934A successfully refreshed from Google Patents.
US3356934A
Expired / Lapsed
US
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Double frequency recording system
Assignee: International Business Machines Corp
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Filing: 1964-11-20
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Granted: 1967-12-05
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Expires: 1984-11-20
Abstract
No abstract record available.
Inventors
- 👤 Martin O Halfhill
- 👤 Harold C Stephens
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 19:01
CPC Classifications
G; G06; G06K; G06K7/00; G06K7/01; G06K7/016; G06K7/0166; G11; G11B; G11B20/00; G11B20/10; G11B20/14; G11B20/1403; G11B20/1407; G11B20/1419
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
90 words
A BINARY RECORDING SYSTEM FOR PRODUCING A RECORDING WAVEFORM HAVING A FLUX REVERSAL AT THE BEGINNING OF EVERY CLOCK INTERVAL AN AN ADDITIONAL FLUX REVERSAL AT THE MIDPOINT OF EACH CLOCK INTERVAL HAVING A SECOND BINARY VALUE, INCLUDING MEANS FOR GENERATING A PULSE TRAIN IN WHICH A PULSE OCCURS AT THE BEGINNING AND AT THE MIDPOINT OF EVEY CLOCK INTERVAL, AND MEANS RESPONSIVE TO DATA OF A FIRST BINARY VALUE FOR BLOCKING PULSES FROM THE PULSE TRAIN WHICH OCCUR AT THE MIDPOINT OF CLOCK INTERVALS HAVING THE FIRST BINARY VALUE.
Claim 2
Dependent Claim
90 words
A BINARY RECORDING SYSTEM FOR PRODUCING A RECORDING WAVEFORM HAVING A FLUX REVERSAL AT THE BEGINNING OF EVERY CLOCK INTERVAL AN AN ADDITIONAL FLUX REVERSAL AT THE MIDPOINT OF EACH CLOCK INTERVAL HAVING A SECOND BINARY VALUE, INCLUDING MEANS FOR GENERATING A PULSE TRAIN IN WHICH A PULSE OCCURS AT THE BEGINNING AND AT THE MIDPOINT OF EVEY CLOCK INTERVAL, AND MEANS RESPONSIVE TO DATA OF A FIRST BINARY VALUE FOR BLOCKING PULSES FROM THE PULSE TRAIN WHICH OCCUR AT THE MIDPOINT OF CLOCK INTERVALS HAVING THE FIRST BINARY VALUE.
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) | 1970-12-04 | 1971-06-05 | 1971-12-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1974-12-04 | 1975-06-05 | 1975-12-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1978-12-04 | 1979-06-05 | 1979-12-05 | $7700.00 | Window Closed / Lapsed |