US3764755A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Automatic tracking system for magnetic video recording and reproducing devices
Assignee: Shiba Electric Co Ltd
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Filing: 1971-09-15
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Granted: 1973-10-09
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Expires: 1991-09-15
Abstract
Abstract The automatic tracking system comprises a circuit including a synchronous three value delta modulator for detecting the maximum value of the signal reproduced from the magnetic tape of the magnetic video recording and reproducing device, a reversible counter for adding or subtracting the signal detected by the circuit, memory means for storing the maximum value of the count of the reversible counter, a digital-analogue converter for converting the stored digital quantity into an analogue quantity, and means responsive to the analogue quantity to adjust the phase of a signal for a capstan driving motor for adjusting the automatic tracking control.
Inventors
- 👤 Y Yamashita
- 👤 K Kimura
- 👤 M Ishikura
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 03:57
CPC Classifications
G; G11; G11B; G11B15/00; G11B15/60; G11B15/602
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
128 words
An automatic tracking system for a magnetic video recording and reproducing device including a capstan driving motor, said system comprising a circuit including a synchronous three value delta modulator for detecting the maximum value of the signal reproduced from the magnetic tape of said magnetic recording and reproducing device and for providing signals in accordance with whether the present reproduced signal occurs before or after said maximum value, a reversible counter, means for adding to or subtracting from the count of said counter in accordance with said signals, a digital-analogue converter for converting the count of said reversible counter into an analogue quantity, and means responsive to said analogue quantity to adjust the phase of a signal for the capstan driving motor for adjusting the automatic tracking control.
Claim 2
Dependent Claim
128 words
An automatic tracking system for a magnetic video recording and reproducing device including a capstan driving motor, said system comprising a circuit including a synchronous three value delta modulator for detecting the maximum value of the signal reproduced from the magnetic tape of said magnetic recording and reproducing device and for providing signals in accordance with whether the present reproduced signal occurs before or after said maximum value, a reversible counter, means for adding to or subtracting from the count of said counter in accordance with said signals, a digital-analogue converter for converting the count of said reversible counter into an analogue quantity, and means responsive to said analogue quantity to adjust the phase of a signal for the capstan driving motor for adjusting the automatic tracking control.
Claim 3
Dependent Claim
149 words
An automatic tracking system for a magnetic recording and reproducing device where a tape advanced by a capstan driving motor has recorded thereon video signals and a track signal, said system, comprising means for reproducing said track signal, a R-S flip-flop circuit responsive to the polarity of a signal produced by rectifying the reproduced video signal for producing a signal of a high level or a low level, a flip-flop circuit responsive to the output from said R-S flip-flop circuit, a reversible counter, a pair of gate circuits responsive to the output from said flip-flop circuit for operating said reversible counter in one direction or other, a D-A converter for converting the digital output from said reversible counter into an analogue quantity, and a phase modulator responsive to said analogue quantity to shift the phase of the reproduced track signal to operate the capstan driving motor of the device.
Claim 4
Dependent Claim
149 words
An automatic tracking system for a magnetic recording and reproducing device where a tape advanced by a capstan driving motor has recorded thereon video signals and a track signal, said system, comprising means for reproducing said track signal, a R-S flip-flop circuit responsive to the polarity of a signal produced by rectifying the reproduced video signal for producing a signal of a high level or a low level, a flip-flop circuit responsive to the output from said R-S flip-flop circuit, a reversible counter, a pair of gate circuits responsive to the output from said flip-flop circuit for operating said reversible counter in one direction or other, a D-A converter for converting the digital output from said reversible counter into an analogue quantity, and a phase modulator responsive to said analogue quantity to shift the phase of the reproduced track signal to operate the capstan driving motor of the device.
Claim 5
Dependent Claim
70 words
The automatic tracking system according to claim 2 which further includes an automatic-manual trasfer switch, a control circuit for controlling the capstan driving motor, and a circuit for providing a signal in accordance with the degree of phase shift between the control track signal and the video signals, said switch selectively connecting said control circuit to either the output of said D-A converter or the output of said signal-providing circuit.
References Cited (Backward Citations)
US3176208A
Cited
US3206665A
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US3495208A
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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) | 1976-10-08 | 1977-04-09 | 1977-10-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-10-08 | 1981-04-09 | 1981-10-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-10-08 | 1985-04-09 | 1985-10-09 | $7700.00 | Window Closed / Lapsed |