Patent US3297565A successfully refreshed from Google Patents.
Patent US3831196A successfully refreshed from Google Patents.
US3831196A
Expired / Lapsed
US
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Magnetic tape recording method and apparatus
Assignee: International Business Machines Corp
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Filing: 1972-08-25
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Granted: 1974-08-20
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Expires: 1992-08-25
Abstract
Abstract A reel-to-reel direct tape drive mechanism is disclosed in which the data recorded on the tape is made insensitive to tape velocity variations during read and write operations by converting each coded character to be recorded into a unique bit count which is recorded so that only a counting operation is necessary to read data recorded on the tape.
Inventors
- 👤 A Thorpe
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 13:54
CPC Classifications
G; G11; G11B; G11B20/00; G11B20/10; G11B20/14; G11B20/1403; G11B20/1423; G11B20/1426
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
50 words
A method of recording multi-bit coded data characters on magnetic media, comprising the steps of: converting each said multi-bit coded data character into a unique number of pulses, said number being representative of said data character; and serially recording magnetic representations of said number of pulses on said magnetic media.
Claim 2
Independent Claim
50 words
A method of recording multi-bit coded data characters on magnetic media, comprising the steps of: converting each said multi-bit coded data character into a unique number of pulses, said number being representative of said data character; and serially recording magnetic representations of said number of pulses on said magnetic media.
Claim 3
Dependent Claim
87 words
A magnetic media data storage and retrieval method for handling multi-bit coded data characters, comprising the steps of: converting each said multi-bit coded data character into a unique number of signal pulses, said number being representative of said data character; serially recording magnetic representations of said numbeR of signal pulses sequentially on a magnetic medium; retrieving data from said magnetic medium by sensing said recorded signal pulses, counting said pulses sensed; and reconverting said count of said sensed pulses into a character in a coded data format.
Claim 4
Dependent Claim
87 words
A magnetic media data storage and retrieval method for handling multi-bit coded data characters, comprising the steps of: converting each said multi-bit coded data character into a unique number of signal pulses, said number being representative of said data character; serially recording magnetic representations of said numbeR of signal pulses sequentially on a magnetic medium; retrieving data from said magnetic medium by sensing said recorded signal pulses, counting said pulses sensed; and reconverting said count of said sensed pulses into a character in a coded data format.
Claim 5
Dependent Claim
34 words
The method of claim 2, wherein: said converting and said reconverting steps are each performed separately for both the lower and higher order portions of said coded data characters formatted in multi-bit coding schemes.
Claim 6
Dependent Claim
59 words
Apparatus for magnetically recording data as a number of pulses, comprising: receiving and temporary storage means for holding a coded data character to be recorded; conversion means for converting said coded data character into a unique number of pulses, said number being representative of said data character; and recording means for placing said pulses on a magnetic record media.
Claim 7
Dependent Claim
59 words
Apparatus for magnetically recording data as a number of pulses, comprising: receiving and temporary storage means for holding a coded data character to be recorded; conversion means for converting said coded data character into a unique number of pulses, said number being representative of said data character; and recording means for placing said pulses on a magnetic record media.
Claim 8
Dependent Claim
37 words
Apparatus as described in claim 4, further comprising: sensing means for sensing the presence of said recorded pulses on said magnetic media; reconverting means connected to said sensing means for recoverting said pulses into coded data characters.
Claim 9
Dependent Claim
100 words
Apparatus as described in claim 5, wherein: said conversion means comprises a binary counter for holding said data for conversion and a source of stepping pulses for stepping said counter to zero; said recording means comprises a magnetic recording head and control circuitry therefore which is responsive to said conversion means to record one pulse on said magnetic media for each stepping of said counter; and said reconverting means comprises a binary counter connected to said sensing means for counting the number of said pulses sensed and an inverter means for inverting said count when said pulses have been counted.
Claim 10
Dependent Claim
25 words
A method of recording multi-bit coded data characters on magnetic media, as described in claim 1, wherein: said converting and recording steps are performed simultaneously.
Claim 11
Dependent Claim
30 words
A magnetic media storage and retrieval method as described in claim 2, wherein: said converting and recording steps are performed simultaneously and said reconverting and counting steps are performed simultaneously.
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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) | 1977-08-19 | 1978-02-18 | 1978-08-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-08-19 | 1982-02-18 | 1982-08-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-08-19 | 1986-02-18 | 1986-08-20 | $7700.00 | Window Closed / Lapsed |