Patent US3696255A successfully refreshed from Google Patents.
US3696255A
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Binary data handling system
Assignee: Unisys Corp
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Filing: 1970-11-02
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Granted: 1972-10-03
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Expires: 1990-11-02
Abstract
Abstract Phase encoded binary data is recorded on a storage medium such as magnetic tape. In reading the data from the medium, a read signal is produced that includes data pulses at regular intervals and phase pulses between at least some of the data pulses. Upon the occurrence of each data pulse, a blanking pulse of shorter duration than the interval between data pulses is generated. The read signal is transmitted to a utilization circuit only in the absence of blanking pulses. As the interval between data pulses changes due to variations in transport speed of the medium, the width of the blanking pulses changes proportionately so the ratio of the duration of the blanking pulses to the interval between data pulses remains constant. Specifically, the blanking pulses are generated by a monostable multivibrator that is triggered by the data pulses produced in reading. The duration of the quasistable state of the multivibrator is controlled by a directcurrent voltage derived from the multivibrator output.
Inventors
- 👤 Chia-Cheng King
- 👤 Arnold J Jorgensen
- 👤 Michael I Behr
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 07:14
CPC Classifications
H; H03; H03K; H03K5/00; H03K5/01; H03K5/04; G; G11; G11B; G11B20/00; G11B20/10; G11B20/14; G11B20/1403; G11B20/1407; G11B20/1419
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
210 words
A binary data handling system comprising: a storage medium on which phase encoded binary data is stored; means for reading the data from the medium, the reading means producing a signal including data pulses at regular intervals and phase pulses between at least some of the data pulses; a monostable multivibrator assuming either a stable state or a quasi-stable state; a direct-current control voltage source representative of the Ratio of the duration of the quasi-stable state to the duration of the period of the multivibrator; the multivibrator having a timing capacitor and resistor connected in series across the control voltage source so the voltage across the capacitor changes toward the control voltage in the quasi-stable state, the multivibrator switching from the quasi-stable state to the stable state when the voltage across the capacitor reaches a predetermined value so the duration of the quasi-stable state remains shorter than the interval between successive data pulses and longer than the interval between a data pulse and the following phase pulse; means responsive to each data pulse for switching the multivibrator from the stable state to the quasi-stable state; utilization means; and means for transmitting the signal produced by the reading means to the utilization means only during the stable state of the multivibrator.
Claim 2
Dependent Claim
210 words
A binary data handling system comprising: a storage medium on which phase encoded binary data is stored; means for reading the data from the medium, the reading means producing a signal including data pulses at regular intervals and phase pulses between at least some of the data pulses; a monostable multivibrator assuming either a stable state or a quasi-stable state; a direct-current control voltage source representative of the Ratio of the duration of the quasi-stable state to the duration of the period of the multivibrator; the multivibrator having a timing capacitor and resistor connected in series across the control voltage source so the voltage across the capacitor changes toward the control voltage in the quasi-stable state, the multivibrator switching from the quasi-stable state to the stable state when the voltage across the capacitor reaches a predetermined value so the duration of the quasi-stable state remains shorter than the interval between successive data pulses and longer than the interval between a data pulse and the following phase pulse; means responsive to each data pulse for switching the multivibrator from the stable state to the quasi-stable state; utilization means; and means for transmitting the signal produced by the reading means to the utilization means only during the stable state of the multivibrator.
Claim 3
Dependent Claim
53 words
The system of claim 1, in which the reading means produces signals on two channels including unipolar data pulses, the channel on which they appear indicating their binary values, and phase pulses; and the signal transmitting means transmits only the data pulses to the utilization means to the exclusion of the phase pulses.
Claim 4
Dependent Claim
56 words
The combination of claim 1, in which the storage medium is magnetic tape that moves relative to the reading means as the binary data is being read so that the duration of the quasi-stable state of the multivibrator changes in accordance with the variations in speed of the movement between the tape and the reading means.
Claim 5
Dependent Claim
213 words
In a binary data handling system, the combination comprising: a storage medium on which phase encoded binary data is stored; means for reading the data from the medium, the reading means producing a signal including data pulses at regular intervals and phase pulses between at least some of the data pulses; a monostable multivibrator that assumes a quasi-stable state for a duration of time responsive to the data pulses, and then returns to a stable state, the duration of the quasi-stable state being dependent upon the magnitude of an applied direct current control signal, the duration of the quasi-stable state being shorter than the interval between successive data pulses and longer than the interval between a data pulse and the following phase pulse; means for generating a direct current signal representative of the ratio of the duration of the quasi-stable state to the duration of the period of the multivibrator; means for applying the generated direct current signal to the multivibrator as the control signal to maintain constant the ratio of the duration of the quasi-stable state to the duration of the period as the period varies; utilization means; and means for transmitting the signal produced by the reading means to the utilization means only during the stable state of the monostable multivibrator.
Claim 6
Dependent Claim
213 words
In a binary data handling system, the combination comprising: a storage medium on which phase encoded binary data is stored; means for reading the data from the medium, the reading means producing a signal including data pulses at regular intervals and phase pulses between at least some of the data pulses; a monostable multivibrator that assumes a quasi-stable state for a duration of time responsive to the data pulses, and then returns to a stable state, the duration of the quasi-stable state being dependent upon the magnitude of an applied direct current control signal, the duration of the quasi-stable state being shorter than the interval between successive data pulses and longer than the interval between a data pulse and the following phase pulse; means for generating a direct current signal representative of the ratio of the duration of the quasi-stable state to the duration of the period of the multivibrator; means for applying the generated direct current signal to the multivibrator as the control signal to maintain constant the ratio of the duration of the quasi-stable state to the duration of the period as the period varies; utilization means; and means for transmitting the signal produced by the reading means to the utilization means only during the stable state of the monostable multivibrator.
Claim 7
Dependent Claim
67 words
The system of claim 4, in which the means for generating a direct current signal includes a control capacitor; means for charging the control capacitor while the multivibrator is in one state and for discharging the control capacitor while the multivibrator is in the other state, and means for developing as the control signal a signal that is proportional to the average voltage across the control capacitor.
Claim 8
Dependent Claim
26 words
The system of claim 5, in which the control capacitor is charged by a constant current source and is discharged through a constant current discharge path.
Claim 9
Dependent Claim
14 words
The system of claim 6, in which the constant current discharge path is adjustable.
Claim 10
Dependent Claim
38 words
The system of claim 6, in which the constant current source is continuously coupled to the control capacitor and the constant current discharge path is connected to the control capacitor only while the multivibrator is in one state.
Claim 11
Dependent Claim
29 words
The system of claim 8, in which means are provided for connecting the constant current discharge path to the control capacitor while the multivibrator is in its stable stAte.
Claim 12
Dependent Claim
58 words
The system of claim 5, in which the means for developing a signal that is proportional to the average voltage across the control capacitor is an output capacitor having a substantially larger capacitance than the control capacitor, and a coupling network is provided for charging and discharging the output capacitor responsive to the voltage across the control capacitor.
Claim 13
Dependent Claim
89 words
The system of claim 10, in which the coupling network comprises first and second transistors of one conductivity type operating in tandem between the first capacitor and the output capacitor; and a third transistor of the opposite conductivity type having a base directly connected to the base of the second transistor, an emitter directly connected to the emitter of the second transistor, and a collector connected to a minimum reference potential such that the output capacitor charges through the first and second transistors and discharges through the third transistor.
Claim 14
Dependent Claim
20 words
The system of claim 10, in which the first and second transistors are NPN and the third transistor is PNP.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-10-03 | 1976-04-03 | 1976-10-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-10-03 | 1980-04-03 | 1980-10-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-10-03 | 1984-04-03 | 1984-10-03 | $7700.00 | Window Closed / Lapsed |