US3789379A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Compensation of reproduced signal by measuring a deviation of recorded reference signal
Assignee: Northrop Grumman Innovation Systems LLC
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Filing: 1973-02-23
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Granted: 1974-01-29
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Expires: 1993-02-23
Abstract
Abstract A playback circuit has a first frequency modulated discriminator for discriminating a reference signal reproduced from a recording medium and a second frequency modulated discriminator for discriminating a data signal reproduced from the same recording medium as the reference signal. A shift register storage means is arranged to store the reproduced data signals and to apply them to the second discriminator at a rate determined by a clock signal produced by a voltage controlled oscillator driven by an output signal from the first discriminator.
Inventors
- 👤 I Breikss
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 22:00
CPC Classifications
G; G11; G11B; G11B20/00; G11B20/22; G11B20/225; G11B20/10; G11B20/16
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
221 words
A playback system comprising reference signal input means arranged to be connected to a source of reference signals, first comparing means connected to said reference input signal means for producing an output signal indicative of a variation of the reference signal from a predetermined standard, voltage controlled oscillator means having an input circuit connected to receive said output signal from said comparing means to produce an output signal having a frequency representative of said output signal from said comparing means, data input signal means arranged to be connected to a source of data signals having a variable repetition rate, signal storing means having an input circuit connected to said data input means and an output circuit and arranged to store a predetermined number of data signals and to transfer the stored data signals out of said storing means to said output circuit in response to a clock signal, circuit means for applying an output signal from said voltage controlled oscillator as a clock signal to said storing means, output terminal means, and second comparing means having an input circuit connected to said output circuit of said storing means and an output circuit connected to said output terminal means and arranged to produce an output signal for applying to said output terminal means representative of the repetition rate of the data signals.
Claim 2
Dependent Claim
221 words
A playback system comprising reference signal input means arranged to be connected to a source of reference signals, first comparing means connected to said reference input signal means for producing an output signal indicative of a variation of the reference signal from a predetermined standard, voltage controlled oscillator means having an input circuit connected to receive said output signal from said comparing means to produce an output signal having a frequency representative of said output signal from said comparing means, data input signal means arranged to be connected to a source of data signals having a variable repetition rate, signal storing means having an input circuit connected to said data input means and an output circuit and arranged to store a predetermined number of data signals and to transfer the stored data signals out of said storing means to said output circuit in response to a clock signal, circuit means for applying an output signal from said voltage controlled oscillator as a clock signal to said storing means, output terminal means, and second comparing means having an input circuit connected to said output circuit of said storing means and an output circuit connected to said output terminal means and arranged to produce an output signal for applying to said output terminal means representative of the repetition rate of the data signals.
Claim 3
Dependent Claim
38 words
A playback system as set forth in claim 1 wherein said data signals are frequency modulated signals and said second means for comparing includes a frequency modulated discriminator arranged to discriminate the data signals from said storage means.
Claim 4
Dependent Claim
106 words
A playback system as set forth in claim 1 wherein said first comparing means includes a phase detector for comparing a pair of input signals applied thereto and producing an output signal representative of the difference in phase of the compared input signals, a fixed frequency reference oscillator means, first circuit means arranged to connect an output signal from said reference oscillator means as a first input signal to said phase detector means and second circuit means arranged to connect said reference signal input terminal to a second input circuit of said phase detector means to apply a second input signal to said phase detector means.
Claim 5
Dependent Claim
31 words
A playback system as set forth in claim 1 wherein said means for comparing includes means for adjusting the phase and amplitude of an output signal from said means for comparing.
Claim 6
Dependent Claim
31 words
A playback system as set forth in claim 2 wherein said first comparing means includes a frequency modulated discriminator arranged to discriminate the reference signals from said reference signal input means.
Claim 7
Dependent Claim
17 words
A playback system as set forth in claim 5 wherein said storing means is a shift register.
References Cited (Backward Citations)
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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) | 1977-01-28 | 1977-07-30 | 1978-01-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-01-28 | 1981-07-30 | 1982-01-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-01-28 | 1985-07-30 | 1986-01-29 | $7700.00 | Window Closed / Lapsed |