US3894201A
Expired / Lapsed
US
⏱️ 0.0 years remaining
System for dynamic and static muting
Assignee: RCA Licensing Corp
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Filing: 1974-05-31
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Granted: 1975-07-08
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Expires: 1994-05-31
Abstract
Abstract A system for providing dynamic and static muting of the subchannel amplifier circuit in a four-channel record demodulator by means of an R-C comparator network which couples and compares the frequency and phase of the subchannel output to a synchronized signal from a phase-locked loop oscillator circuit. The comparator network generates an error signal when the frequency and phase of the compared signals are not synchronized, which error signal biases a field effect transistor into conduction, thereby shunting the subchannel information from the audio output.
Inventors
- 👤 Gerald Dee Pyles
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 16:53
CPC Classifications
H; H04; H04S; H04S3/00; H04S3/006
Claims Analysis
Total Claims: 35
Claim 1
Independent Claim
314 words
In a system for reproducing multichannel sound from a record medium having at least a main audio signal channel and a superaudible modulated subcarrier signal channel, a system for providing muting of the subcarrier signal channel comprising: 1. means for recovering from said medium said main audio frequency signal components and superaudible modulated subcarrier signal components; 2. a sound reproducing system; 3. channel filtering means coupled to said recovering means for separatIng out said main audio frequency signal components from said superaudible modulated subcarrier signal components; 4. a signal processing channel coupled to said filtering means for demodulation of said separated subcarrier signal components and for coupling resultant demodulated subcarrier signal components to said sound reproducing system; and 5. means for muting said signal processing channel comprising: a. a phase-locked loop circuit coupled to said filtering means for generating an output signal representative of the output signal of said filtering means when variations in the output signal of said filtering means are within predetermined limits and for generating an output signal independent of the output signal of said filtering means in a first instance when said variations are not within said predetermined limits, and in a second instance when said output signal of said filtering means is substantially absent; b. means coupled between said filtering means and said phaselocked loop circuit for comparing the output signals of said filtering means and phase-locked loop circuit and for generating an error signal when said output signals are different, and for providing a cancellation effect when said output signals are the same; c. means responsive to said error signal for decoupling said signal processing channel from said sound reproducing system, thereby muting said demodulated subcarrier signal channel; and 6. signal combining means for coupling said main audio frequency signal components and the resultant demodulated subcarrier signal components of said signal processing channel to said sound reproducing system.
Claim 2
Dependent Claim
314 words
In a system for reproducing multichannel sound from a record medium having at least a main audio signal channel and a superaudible modulated subcarrier signal channel, a system for providing muting of the subcarrier signal channel comprising: 1. means for recovering from said medium said main audio frequency signal components and superaudible modulated subcarrier signal components; 2. a sound reproducing system; 3. channel filtering means coupled to said recovering means for separatIng out said main audio frequency signal components from said superaudible modulated subcarrier signal components; 4. a signal processing channel coupled to said filtering means for demodulation of said separated subcarrier signal components and for coupling resultant demodulated subcarrier signal components to said sound reproducing system; and 5. means for muting said signal processing channel comprising: a. a phase-locked loop circuit coupled to said filtering means for generating an output signal representative of the output signal of said filtering means when variations in the output signal of said filtering means are within predetermined limits and for generating an output signal independent of the output signal of said filtering means in a first instance when said variations are not within said predetermined limits, and in a second instance when said output signal of said filtering means is substantially absent; b. means coupled between said filtering means and said phaselocked loop circuit for comparing the output signals of said filtering means and phase-locked loop circuit and for generating an error signal when said output signals are different, and for providing a cancellation effect when said output signals are the same; c. means responsive to said error signal for decoupling said signal processing channel from said sound reproducing system, thereby muting said demodulated subcarrier signal channel; and 6. signal combining means for coupling said main audio frequency signal components and the resultant demodulated subcarrier signal components of said signal processing channel to said sound reproducing system.
Claim 3
Dependent Claim
4 words
a sound reproducing system;
Claim 4
Dependent Claim
4 words
a sound reproducing system;
Claim 5
Dependent Claim
60 words
A muting system according to claim 1 in which said muting means provides dynamic muting in a first instance when said variations in said output signal of said filtering means are not within said predetermined limits and in which said muting means provides static muting in a second instance when said output signal of said filtering means is substantially absent.
Claim 6
Dependent Claim
4 words
a sound reproducing system;
Claim 7
Dependent Claim
4 words
a sound reproducing system;
Claim 8
Dependent Claim
24 words
channel filtering means coupled to said recovering means for separatIng out said main audio frequency signal components from said superaudible modulated subcarrier signal components;
Claim 9
Dependent Claim
24 words
channel filtering means coupled to said recovering means for separatIng out said main audio frequency signal components from said superaudible modulated subcarrier signal components;
Claim 10
Dependent Claim
59 words
A muting system according to claim 1 in which said means for decoupling said signal processing channel from said sound reproducing system comprises an active device having a control electrode and a main current conducting path, said active device being responsive to a bias level at said control electrode for providing a variable impedance in said main current path.
Claim 11
Dependent Claim
24 words
channel filtering means coupled to said recovering means for separating out said main audio frequency signal components from said superaudible modulated subcarrier signal components;
Claim 12
Dependent Claim
24 words
channel filtering means coupled to said recovering means for separating out said main audio frequency signal components from said superaudible modulated subcarrier signal components;
Claim 13
Dependent Claim
31 words
a signal processing channel coupled to said filtering means for demodulation of said separated subcarrier signal components and for coupling resultant demodulated subcarrier signal components to said sound reproducing system; and
Claim 14
Dependent Claim
31 words
a signal processing channel coupled to said filtering means for demodulation of said separated subcarrier signal components and for coupling resultant demodulated subcarrier signal components to said sound reproducing system; and
Claim 15
Dependent Claim
46 words
A muting system according to claim 3 in which said control electrode of said active device is biased by said error signal, said bias rendering said main current conducting path conductive, thereby attenuating said signal processing channel to provide muting of said demodulated subcarrier signal channel.
Claim 16
Dependent Claim
31 words
a signal processing channel coupled to said filtering means for demodulation of said separated subcarrier signal components and for coupling resultant demodulated subcarrier signal components to said sound reproducing system; and
Claim 17
Dependent Claim
31 words
a signal processing channel coupled to said filtering means for demodulation of said separated subcarrier signal components and for coupling resultant demodulated subcarrier signal components to said sound reproducing system; and
Claim 18
Dependent Claim
166 words
means for muting said signal processing channel comprising: a. a phase-locked loop circuit coupled to said filtering means for generating an output signal representative of the output signal of said filtering means when variations in the output signal of said filtering means are within predetermined limits and for generating an output signal independent of the output signal of said filtering means in a first instance when said variations are not within said predetermined limits, and in a second instance when said output signal of said filtering means is substantially absent; b. means coupled between said filtering means and said phase-locked loop circuit for comparing the output signals of said filtering means and phase-locked loop circuit and for generating an error signal when said output signals are different, and for providing a cancellation effect when said output signals are the same; c. means responsive to said error signal for decoupling said signal processing channel from said sound reproducing system, thereby muting said demodulated subcarrier signal channel; and
Claim 19
Dependent Claim
166 words
means for muting said signal processing channel comprising: a. a phase-locked loop circuit coupled to said filtering means for generating an output signal representative of the output signal of said filtering means when variations in the output signal of said filtering means are within predetermined limits and for generating an output signal independent of the output signal of said filtering means in a first instance when said variations are not within said predetermined limits, and in a second instance when said output signal of said filtering means is substantially absent; b. means coupled between said filtering means and said phase-locked loop circuit for comparing the output signals of said filtering means and phase-locked loop circuit and for generating an error signal when said output signals are different, and for providing a cancellation effect when said output signals are the same; c. means responsive to said error signal for decoupling said signal processing channel from said sound reproducing system, thereby muting said demodulated subcarrier signal channel; and
Claim 20
Dependent Claim
146 words
means for muting said signal processing channel comprising: a. a phase-locked loop circuit coupled to said filtering means for generating an output signal representative of the output signal of said filtering means when variations in the output signal of said filtering means are within predetermined limits and for generating an output signal independent of the output signal of said filtering means when said variations are not within said predetermined limits; b. means coupled between said filtering means and said phase-locked loop circuit for comparing the output signals of said filtering means and phase-locked loop circuit and for generating an error signal when said output signals are different, and for providing a cancellation effect when said output signals are the same; c. means responsive to said error signal for decoupling said signal processing channel from said sound reproducing system, thereby muting said demodulated subcarrier signal channel; and
Claim 21
Dependent Claim
146 words
means for muting said signal processing channel comprising: a. a phase-locked loop circuit coupled to said filtering means for generating an output signal representative of the output signal of said filtering means when variations in the output signal of said filtering means are within predetermined limits and for generating an output signal independent of the output signal of said filtering means when said variations are not within said predetermined limits; b. means coupled between said filtering means and said phase-locked loop circuit for comparing the output signals of said filtering means and phase-locked loop circuit and for generating an error signal when said output signals are different, and for providing a cancellation effect when said output signals are the same; c. means responsive to said error signal for decoupling said signal processing channel from said sound reproducing system, thereby muting said demodulated subcarrier signal channel; and
Claim 22
Dependent Claim
51 words
A muting system according to claim 4 in which said active device is a field effect transistor having a gate as a control electrode and a main current conducting path, said transistor being responsive to a bias level at said gate for providing a variable impedance in said main current path.
Claim 23
Dependent Claim
57 words
A muting system according to claim 1 in which said comparator means comprises an R-C coupled network adjusted to yield a minimum or cancellation effect when the superaudible modulated subcarrier signal is reasonably free of spurious amplitude and frequency variations and to yield an error signal when said superaudible signal is not free of such spurious variations.
Claim 24
Dependent Claim
28 words
signal combining means for coupling said main audio frequency signal components and the resultant demodulated subcarrier signal components of said signal processing channel to said sound reproducing system.
Claim 25
Dependent Claim
28 words
signal combining means for coupling said main audio frequency signal components and the resultant demodulated subcarrier signal components of said signal processing channel to said sound reproducing system.
Claim 26
Dependent Claim
28 words
signal combining means for coupling said main audio frequency signal components and the resultant demodulated subcarrier signal components of said signal processing channel to said sound reproducing system.
Claim 27
Dependent Claim
28 words
signal combining means for coupling said main audio frequency signal components and the resultant demodulated subcarrier signal components of said signal processing channel to said sound reproducing system.
Claim 28
Dependent Claim
71 words
A muting system according to claim 1 in which said phase-locked loop circuit comprises a controlled oscillator for generating an output signal, a phase comparator responsive to the output of said main channel filtering means and said controlled oscillator for providing a control signal and loop filtering means for filtering said control signal and for coupling a resultant filtered control signal to said controlled oscillator whose output signal is controlled thereby.
Claim 29
Dependent Claim
36 words
A muting system according to claim 7 in which the output signal of said phase-locked loop unrelated to said filtering means output signal Is a signal characteristic of the free-running frequency signal of the controlled oscillator.
Claim 30
Dependent Claim
29 words
A muting system according to claim 1 in which said signal processing channel comprises demodulation circuitry for demodulating said superaudible high frequency signal components into audio frequency signal components.
Claim 31
Dependent Claim
23 words
A muting system according to claim 9 in which said superaudible subcarrier signal components comprise audio information modulated on a 30KHz carrier signal.
Claim 32
Dependent Claim
19 words
A muting system according to claim 7 in which said control signal comprises the demodulated superaudible subcarrier audio information.
Claim 33
Dependent Claim
38 words
A muting system according to claim 7 in which said controlled oscillator is of the voltage controlled type comprising a multivibrator and means for varying the frequency of oscillation of said multivibrator in response to said control signals.
Claim 34
Dependent Claim
37 words
In a system for reproducing multichannel sound from a record medium having at least a main audio signal channel and a superaudible modulated subcarrier signal channel, a system for providing muting of the subcarrier signal channel comprising:
Claim 35
Dependent Claim
37 words
In a system for reproducing multichannel sound from a record medium having at least a main audio signal channel and a superaudible modulated subcarrier signal channel, a system for providing muting of the subcarrier signal channel comprising:
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) | 1978-07-07 | 1979-01-06 | 1979-07-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-07-07 | 1983-01-06 | 1983-07-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-07-07 | 1987-01-06 | 1987-07-08 | $7700.00 | Window Closed / Lapsed |