Abstract:
A process and network able to restrict a video appliance equipped with either a single tuner or with multiple tuners, from receiving and subsequently displaying video image signals represented by an accompanying broadcast discretionary control data to include a high level of objectional content. A multi-tuner television receiving appliance may be constructed with at least two tuners receiving a program; a viewing restricting portion detecting a discretionary control data of the program received through one of the tuners and blocking AGC signals of the tuner receiving the program when the discretionary control data is greater than a discretionary threshold; a control portion blocking AFT signals of the other tuners when the viewing of the program received the receiving tuner is restricted.

Description:
CLAIM FOR PRIORITY  
         [0001]    This application makes reference to, incorporates the same herein, and claims all benefits accruing under 35 U.S.C. §119 from my Korean Patent Application No. 2000-6163, earlier filed in the Korean Industrial Property Office on Feb. 10, 2000, the entirety of which is hereby incorporated by reference.  
         BACKGROUND OF THE INVENTION  
         [0002]    1. Field of the Invention  
           [0003]    The present invention relates to single and multi-tuner television receiving techniques and apparatus generally, and more particularly, to a process and circuit that enable a user to restrict viewing of selected video image programs of an appliance equipped with either a single or a multiple number of television tuners.  
           [0004]    2. Description of the Background Art  
           [0005]    Recent proposed changes in federal regulations within the United States mandate that a discretionary control feature, commonly called the “V-chip” function, be incorporated into the design and construction of consumer television receiver circuits. This V-chip function allows a parent or other responsible person discretionary control to block-out television programs that the parent deems to be inappropriate for young viewers. The V-chip function may be implemented by incorporatation into one or more dedicated ICs or by inclusion in a microprocessor. The proposed discretionary control feature will be encoded and transmitted to television receivers on the twenty-first (i.e., line  21 ) line of the 525 horizontal scanned lines that make up one frame of each picture screen. Each transmission of line  21  contains a synchronizing clock burst that is followed by data. The data contained within line  21  also contains closed captioning information to display words (i.e., descriptive text) on the television screen for hearing impaired viewers. Line  21  data further includes discretionary control data with a value representing the level of sex and violence in the corresponding video program that is currently being run. The discretionary control data is fed into the microprocessor or V-chip integrated circuit. The parent pre-sets a discretionary threshold for the television receiver. If the discretionary control data carried by line  21  is less than the discretionary threshold set for the television receiver, then the amount and degree of sex and violence in the currently running program is considered to be acceptable, and the viewer is allowed to watch the program. If the discretionary control data is greater than the discretionary threshold then the amount and degree of sex and violence in the presently running program is considered to be unacceptable, and the video signal carried by that channel is blanked out, or otherwise made unviewable.  
           [0006]    Applicances for watching video programs have been constructed in recent years with multiple tuners. Video appliances constructed with two or more tuners, such as television receivers coupled with video cassette recorders (i.e., a TVCR), have been proposed for example, by Sung-doug Kim in an  Apparatus For Performing Programmed Recording Using Broadcast Program Data and Method Therefor In a Two - tuner System , U.S. Pat. No. 6,058,242 issued on May 2, 2000. These multi-tuner video appliances are also sometimes referred to as “TV/VCR combos” by retail vendors such as Circuit City.  
           [0007]    I have noticed however, that this type of supervisory discretionary control can be implemented out only for video receiving appliances that have a single tuner. Therefore, a viewer can watch a program that carries discretionary control data with a value that is greater than the discretionary threshold by using multiple devices or by using a device equipped with two turners, for example, a TV coupled with a video cassette recorder (e.g., a VCR or a TVCR). In further detail, if the value of the discretionary control data for a program is greater than the discretionary threshold value that has been set by the user of that video appliance, a video signal received through a TV receiving tuner is blanked out or made unviewable, whereas the same program can be recorded onto a video cassette tape through the recording tuner of the VCR. Consequently, I have found that the discretionary control function can not be easily and fully implemented with a video receiving appliance that has more than two tuners such as a TVCR, and that there is a need for a television receiving apparatus that performs the discretionary control function even when the receiving apparatus has more than two tuners such as a TVCR, and a method of restricting the viewing of selected video programs via video receiving appliances that are equipped with multiple tuners.  
         SUMMARY OF THE INVENTION  
         [0008]    It is therefore, an object of the present invention to provide an improved process and apparatus for viewing video programs.  
           [0009]    It is another object to provide a process and apparatus able to restrict the viewing of programs via a video appliance that is equipped either with a single tuner or with multiple tuners.  
           [0010]    It is a still further object to provide a video display appliance and process for operating the appliance that is equipped either with a single tuner or with multiple tuners, to enable entry of a single restrictive viewing setting to simultaneously control viewing access to video signals that could otherwise be received by any of the multiple tuners.  
           [0011]    It is a yet further object to provide a television receiving apparatus that performs a discretionary control function even in video receiving apparatus that is equipped either with a single tuner or with multiple tuners such as a TVCR, and a method of restricting the viewing of programs with such receiving apparatus.  
           [0012]    It is still yet a further object to provide a simplified process and circuit able to restrict viewing of video image programs with a video appliance that is equipped either with a single tuner or with multiple tuners independently operable tuners.  
           [0013]    These and other objects may be attained with a television receiving apparatus and process that is equipped either with a single tuner or with multiple tuners receiving a program. One stage of the network for the video appliance serves to restrict viewing via the appliance by detecting the discretionary control data for the program that is being received through one of the tuners and by blocking the automatic gain control signals (i.e., the AGC signals) of the tuner that is receiving the program when the discretionary control data is greater than the discretionary threshold. A control stage of the network blocks the automatic fine tuning signals (i.e. the AFT signals) of the other tuners within the appliance when the viewing of the program received by the receiving tuner is restricted by the setting of the discretionary threshold.  
           [0014]    Another embodiment of the present invention provides a process for restricting the viewing of video programs of video appliances such as televison receivers, video cassette receivers and read and writing digital video disk players, that are equipped either with a single tuner or with multiple tuners, a viewing restriction stage and a control stage. The discretionary control data for the program that is being received through the first tuner is detected, and a comparison is made between the value of the discretionary threshold installed by the user in the appliance and the discretionary control data detected for the video signal being received. A check is made to determine whether a viewer has made a recording command through any of the other tuners of the appliance when the detected discretionary control data that has been received for the program is less than the installed viewing restriction data. The automatic gain control signals are blocked by the view restriction stage for the tuner receiving the program when the value indicated by the discretionary control data is greater than the discretionary threshold, and the automatic fine tuning signals for the second tuner are blocked by the control stage when a comparison between the discretionary control data and the discretionary threshold indicates that viewing of the corresponding program being received by the receiving tuner is restricted.  
           [0015]    Either a single tuner or a multi-tuner television receiving apparatus may be used as a preferred embodiment of the present invention, so that when the discretionary control data in the currently running program is greater than the discretionary threshold, not only one tuner of the video appliance, but also all of the other tuners of the appliance are blocked, whereupon no one is able to use that appliance to view the program that the parents have deemed to be inappropriate for young viewers. Additionally, since the principles of the present invention may be implemented with a transistor used to block the automatic fine tuning signals in order to lock the second tuner, both the circuit and the operational program for implementing the principles of this invention may be simplified. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0016]    A more complete appreciation of this invention, and many of the attendant advantages thereof, will be readily apparent as the same becomes better understood by reference to the following detailed description when considered in conjunction with the accompanying drawings in which like reference symbols indicate the same or similar components, wherein:  
         [0017]    [0017]FIG. 1 is a block diagram illustrating a circuit that provides supervisory regulation of the viewing provided by a single tuner television appliance constructed as a preferred embodiment of the present invention;  
         [0018]    [0018]FIG. 2 is a flow chart illustrating one process for operating a single tuner video appliance, as another preferred embodiment of the present invention;  
         [0019]    [0019]FIG. 3 is a block diagram illustrating a circuit that provides supervisory regulation of the viewing provided by a single tuner VCR constructed as a preferred embodiment of the present invention;  
         [0020]    [0020]FIG. 4 is a block diagram illustrating a circuit for a two-tuner TVCR constructed as a preferred embodiment of the present invention; and  
         [0021]    [0021]FIG. 5 is a flow chart illustrating one process for operating a two-tuner TVCR, as another preferred embodiment of the present invention. 
     
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS  
       [0022]    Embodiments of the present invention will hereinafter be described in detail through a preferred embodiment of the present invention, with reference to the accompanying drawings. FIG. 1 shows a circuit of a television receiver  80  that is equipped with a single tuner  12 , constructed according to one design for a preferred embodiment of the present invention. An antenna  8 , or some other source of video image signals such as a cable modem, respectively applying either broadcast or cable image video signals via signal lead  11  to tuner  12  that feeds selector  16 , a video processor  20 , a display controller  24 , and a video display  25 . View restricting stage  26 , selector  28 , memory  30  and command input stage  32  are disposed to receive commands and operational instructions from a user as a result of the user&#39;s manual maniplulations of a multikey keypad for a hand-held remote controller  36 , and a control stage such as a microprocessor based controller  34 . The control electrode of a first transistor Q 1  is coupled to be driven by signals output from pin S 3  of controller  34 .  
         [0023]    Video image signals that are being received through tuner  12 , are selectively provided to video processing stage  20  through selector  16 . Optionally, selector  16  may provide a single image signal received via either tuner  12  or via some other source to video processor  20 .  
         [0024]    VCR circuit  18  divides the received multiple image signals into brightness signals and color signals, processes the brightness and color signals, and then frequency modulates the brightness and color signals. These frequency modulated brightness and color signals are transferred to a recording deck  22 , where the image signals are recorded onto a recording medium such as a video cassette tape. Alternatively, or in addition, a different switch (not shown) may selectively apply either video image signals reproduced from a video tape to video processor  20 , or provide the video image signals received by tuner  12  may be applied to a DVD recorder for storage on a DVD disk.  
         [0025]    Video processor  20  receives image signals from tuner  12  or reproduced image signals from either a VCR or DVD circuit (not shown), and processes the brightness signal components and color signal components of the image signals received, and applies red, green and blue signals (i.e., RGB signals) to display controller  24 . Display controller  24  drives a video display device such as a thin film display or a cathode ray tube display  25  that displays RGB image signals on the display portion  25  in response to reception of the synchronizing signals.  
         [0026]    View restriction stage  26  detects the presence of discretionary control data, i.e., V-chip data, contained among the data carried by line  21  of the multiple image signals received by video processor  20 , and feeds the decoded discretionary control data to controller  34  after decoding the detected discretionary control data. View restriction stage  26  maybe constructed as a decoder that provides an output signal to controller  34  that is representative of the discretionary control data carried by line  21 . View restriction stage  26  decides whether the discretionary control data has a value that is less than the discretionary threshold. When a program carried on line twenty-one discretionary control data that indicates a value that is greater than the discretionary threshold that has been most recently set by the supervisory user, view restriction stage  26  blocks the AGC voltage for tuner  12  that is receiving that particular program, through selector  28 , thereby blocking out the television program corresponding to the discretionary control data that the parent of the young viewer deems to be inappropriate.  
         [0027]    The discretionary control data, the discretionary threshold that has been pre-set by a user, a user ID code, and other operational information is written into and read from memory  30  by controller  34 .  
         [0028]    Controller  34  includes a microcomputer and its peripheral circuit. Controller  34  regulates the operation and performance of all of the components of the TV circuit  80  in response to commands input by the user through command input stage  32 . Controller  34  regulates the operation of selector  16  via control signals output on its terminal S 0 . Controller  34  also controls the electrical conductivity through the collector-emitter semiconducting path of transistor Q 1  by contolling the voltage applied by terminal S 3  to the base electrode of transistor Q 1  in response to the control provided by view restriction stage  26  in order to mute the AFT signals for tuner  12  when the indicated value of the discretionary control data that accompanies a video program is greater than the discretionary threshold previously stored in memory  30  by the supervisory user of the appliance.  
         [0029]    [0029]FIG. 2 is a flow chart illustrating one of the several possible operations of a video appliance equipped with one or more discrete tuner stages (e.g., such as video appliance  80  shown in FIG. 1) in accordance with the principles of the present invention. When viewing the video images on display device  25  of a video signal that is received on a channel tuned through tuner  12 , the operation to restrict viewing of video images carried by one, or more channels is as follows.  
         [0030]    During step  100 , when the broadcast signal is received through the first tuner  12 , controller  34  generates control signals on its terminal S 0  to switch selector  16  so that a multiple image signal provided by tuner  12  may be applied to video processor  20 . Controller  34  also generates a control signal at terminal S 2  to switch selector  28  to apply the automatic gain contol signals AGC for tuner  12 . Subsequently, during step  102 , the multiple image signal received through tuner  12  is applied to view restriction stage  26  to be decoded to allow detection of the discretionary control data carried by line  21  data. Then, in step  104  controller  34  makes a determination of whether the program currently being received is accompanied by discretionary control data that indicates a value that is less than the discretionary threshold currently stored in memory  30 ? When the value indicated by the discretionary control data carried by line  21  is less than the discretionary threshold, the AGC signal for tuner  12  is maintained during step  106  “as is” in order to continue application of the AGC signal to the tuner  12  so that the viewer will be allowed to watch the program that corresponds to the discretionary control data.  
         [0031]    When the value of the discretionary control data carried by line  21  is greater than the discretionary threshold most recently stored in memory  30 , the receiving operation of tuner  12  is locked in step  112  by generation of a control signal S 2  to cause actuator  28  to block transmission of the AGC signal to tuner  12 . As a result, it becomes impossible for the viewer to watch any program of video images through tuner  12  that has a value indicated by its accompanying discretionary control data which is greater than the discretionary threshold.  
         [0032]    When a recording command is received by controller  34  from command input stage  32  for the same channel as is currently being received through the second tuner, the control voltage applied to the base of transistor Q 1  by terminal S 3  turns transistor Q 1  on so that AFT signals for second tuner  12  are shunted to either ground or to a local reference potential by the collector-emitter path of transistor Q 1  and the reception of that channel via second tuner  12  is blocked, thus locking the receiving operation of the multiple tuner appliance and thereby restricting reception to only those channels that are received through first tuner  10 . At the same time, during step  112  the AGC signals of tuner  12  are also blocked by third selector  28 , thereby preventing second tuner  12  from being used to receive any channel when the value of the discretionary control data carried by line  21  of a video image signal on that channel is greater than the discretionary threshold most recently stored in memory  21 . Therefore, it is impossible to either record or to view any program received via tuner  21  that has discretionary control data that is greater in value than the discretionary threshold.  
         [0033]    [0033]FIG. 3 shows a circuit of a video cassette recorder  90  as an exemplar of another single tuner video appliance constructed according to one design for a preferred embodiment of the present invention, with tuner  10 . Antenna  7 , or some other source of video image signals such as a cable modem, respectively applying either broadcast or cable video image signals via signal lead  9  to tuner  10  that selectively feeds selector  14 , respectively applying either broadcast or cable image video signals via selector  14  to a video cassette recorder circuit (i.e., a VCR circuit)  18 . View restricting stage  26 , selector  28 , memory  30 , and command input stage  32  disposed to receive commands and operational instructions from a user as a result of the user&#39;s manual maniplulations of a multikey keypad for a hand-held remote controller  36 , and a control stage such as a microprocessor based controller  34 . The control electrode transistor Q 2  is coupled to be driven by signals output from pin S 4  of controller  34 .  
         [0034]    Video image signals that are being received through tuner  10 , are selectively provided to VCR circuit  18  through selector  14 . Optionally, selector  14  may provide a single image signal received via either tuner  10  or some other source to both VCR circuit  18  and some other video appliance.  
         [0035]    VCR circuit  18  divides the received multiple image signals into brightness signals and color signals, processes the brightness and color signals, and then frequency modulates the brightness and color signals. These frequency modulated brightness and color signals are transferred to a recording deck  22 , where the image signals are recorded onto a recording medium such as a video cassette tape. Alternatively, or in addition, a different switch (not shown) may selectively apply the image signals provided by tuner  10  to a DVD recorder for storage on a DVD disk.  
         [0036]    Image signals reproduced from the tape by recording deck  22  are FM-demodulated by VCR circuit  18  and then are provided for viewing and entertainment to a video processor for a televison set, such as processor  20  shown in FIG. 1.  
         [0037]    View restriction stage  26  detects the presence of discretionary control data, i.e., V-chip data, contained among the data carried by line  21  of the multiple image signals received by video processor  20 , and feeds the decoded discretionary control data to controller  34  after decoding the detected discretionary control data. View restriction stage  26  maybe constructed as a decoder that provides an output signal to controller  34  that is representative of the discretionary control data carried by line  21 . View restriction stage  26  decides whether the discretionary control data has a value that is less than the discretionary threshold. When a program has discretionary control data that indicates a value that is greater than the discretionary threshold that has been most recently set by the supervisory user, view restriction stage  26  blocks the AGC voltage for tuner  10  that is receiving that particular program, through selector  28 , thereby blocking out the television program corresponding to the discretionary control data that the parent of the young viewer deems to be inappropriate.  
         [0038]    The discretionary control data, the discretionary threshold that has been pre-set by a user, a user ID code, and other operational information is written into and read from memory  30  by controller  34 .  
         [0039]    Controller  34  includes a microcomputer and its peripheral circuit. Controller  34  regulates the operation and performance of all of the components of appliance  90  in response to commands input by the user through command input stage  32 . Controller  34  regulates the operation of selector  14  via control signals output on its terminals S 1 . Controller  34  also controls the electrical conductivity through the collector-emitter semiconducting path of transistor Q 2  by contolling the voltage applied by terminal S 4  to the base electrodes of transistor Q 2  in response to the control provided by view restriction stage  26  in order to mute the AFT signals for tuner  10  when the indicated value of the discretionary control data that accompanies a video program is greater than the discretionary threshold previously stored in memory  30  by the supervisory user of the appliance.  
         [0040]    [0040]FIG. 4 shows a circuit of a two-tuner TVCR  200  constructed according to one design for a preferred embodiment of the present invention, with two independently operable tuners  10 ,  12 . The two-tuner TVCR includes either a first antenna  7 , or some other source of video image signals such as a cable modem, respectively applying either broadcast or cable video image signals via a first signal lead  9  to first tuner  10  that selectively feeds first selector  14  and second selector  16 , either a second antenna  8 , or some other source of video image signals such as a cable modem, respectively applying either broadcast or cable image video signals via a second signal lead  11  to second tuner  12  that feeds first selector  14  and second selector  16 , a video cassette recorder circuit (i.e., a VCR circuit)  18 , a video processor  20 , a display controller  24 , a video display  25 , a view restricting stage  26 , a third selector  28 , a memory  30 , a command input stage  32  disposed to receive commands and operational instructions from a user as a result of the user&#39;s manual maniplulations of a multikey keypad for a hand-held remote controller  36 , and a control stage such as a microprocessor based controller  34 . The control electrode of a first transistor Q 1  is coupled to be driven by signals output from pin S 3  of controller  34 , and the control electrode of a second transistor Q 2  is coupled to be driven by signals output from pin S 4  of controller  34 .  
         [0041]    Multiple image signals that are being simultaneously received through different ones of independently variable first and second tuners  10 ,  12 , are selectively provided to VCR circuit  18  through first selector  14  and to video processor  20  through second selector  16 . Optionally, selectors  14 ,  16  may provide a single image signal received via either tuner  10  or tuner  12  to both VCR circuit  18  and video processor  20 .  
         [0042]    VCR circuit  18  divides the received multiple image signals into brightness signals and color signals, processes the brightness and color signals, and then frequency modulates the brightness and color signals. These frequency modulated brightness and color signals are transferred to a recording deck  22 , where the image signals are recorded onto a recording medium such as a video cassette tape. Alternatively, or in addition, a different switch (not shown) may selectively apply the image signals provided by tuners  10 ,  12  to a DVD recorder for storage on a DVD disk.  
         [0043]    Image signals reproduced from the tape by recording deck  22  are FM-demodulated by VCR circuit  18  and then are provided to video processor  20 . Video processor  20  receives multiple image signals from either tuners  10 ,  12  or reproduced image signals from VCR circuit  18 , or from another source of reproduction such as a DVD player (not shown), and processes the brightness signal components and color signal components of the image signals received, and applies red, green and blue signals (i.e., RGB signals) to display controller  24 . Display controller  24  drives a video display device such as a thin film display or a cathode ray tube display  25  that displays RGB image signals on the display portion  25  in response to reception of the synchronizing signals.  
         [0044]    View restriction stage  26  detects the presence of discretionary control data, i.e., V-chip data, contained among the data carried by line  21  of the multiple image signals received by video processor  20 , and feeds the decoded discretionary control data to controller  34  after decoding the detected discretionary control data. View restriction stage  26  maybe constructed as a decoder that provides an output signal to controller  34  that is representative of the discretionary control data carried by line  21 . View restriction stage  26  decides whether the discretionary control data has a value that is less than the discretionary threshold. When a program has discretionary control data that indicates a value that is greater than the discretionary threshold that has been most recently set by the supervisory user, view restriction stage  26  blocks the AGC voltage for the corresponding tuner  10 ,  12  that is receiving that particular program through third selector  28 , thereby blocking out the television program corresponding to the discretionary control data that the parent of the young viewer deems to be inappropriate.  
         [0045]    The discretionary control data, the discretionary threshold that has been pre-set by a user, a user ID code, and other operational information is written into and read from memory  30  by controller  34 .  
         [0046]    Controller  34  includes a microcomputer and its peripheral circuit. Controller  34  regulates the operation and performance of all of the components of the TVCR circuit in response to commands input by the user through command input stage  32 . Controller  34  regulates the operation of selectors  14 ,  16  via control signals output on its terminals S 1 , S 0 , respectively. Controller  34  also controls the electrical conductivity through the collector-emitter semiconducting path of first and second transistors Q 1 , Q 2  by contolling the voltages applied by terminals S 3 , S 4  to the respective base electrodes of transistors Q 1 , Q 2  in response to the control provided by view restriction stage  26  in order to mute the AFT signals for either of the two tuners  10 ,  12  when the indicated value of the discretionary control data that accompanies a video program is greater than the discretionary threshold previously stored in memory  30  by the supervisory user of the appliance.  
         [0047]    [0047]FIG. 5 is a flow chart illustrating one of the several possible operations of the two-tuner TCVR equipped with two, or more discrete tuner stages (e.g., such as the embodiment shown in FIG. 1) in accordance with the principles of the present invention. When viewing the video images on display device  25  of a video signal that is received on a channel tuned through second tuner  12  and simultaneously recording a channel selected through first tuner  10  by using the VCR, the operation to restrict viewing of video images carried by one, or more channels is as follows.  
         [0048]    During step  100 , when the broadcast signal is received through second tuner  12 , controller  34  generates control signals on its terminals S 0  and S 1  respectively to switch second selector  16  so that a multiple image signal provided by second tuner  12  may be applied to video processor  20 , and to switch first selector  14  so that a multiple image signal provided by first tuner  10  maybe applied to VCR circuit  18 . Controller  34  also generates a control signal at terminal S 2  to switch third selector  28  to apply the automatic gain contol signals AGC for second tuner  12 . Subsequently, during step  102 , the multiple image signal received through second tuner  12  is applied to view restriction stage  26  to be decoded to allow detection of the discretionary control data carried by line  21  data. Then, in step  104  controller  34  makes a determination of whether the program currently being received is accompanied by discretionary control data that indicates a value that is less than the discretionary threshold currently stored in memory  30 ? When the value indicated by the discretionary control data carried by line  21  is less than the discretionary threshold, the AGC signal of the second tuner  12  is maintained during step  106  “as is” in order to continue application of the AGC signal to the second tuner so that the viewer will be allowed to watch the program that corresponds to the discretionary control data.  
         [0049]    When the value of the discretionary control data carried by line  21  is greater than the discretionary threshold most recently stored in memory  30 , controller  34  makes a check during step  108  to determine whether a recording command has been received for the same channel through first tuner  10 . When no recording command is determined by step  108  to have been received for the first tuner, the receiving operation of second tuner  12  is locked in step  112  by generation of a control signal S 2  to cause third actuator  28  of block transmission of the AGC signal to second tuner  12 . As a result, it becomes impossible for the viewer to watch any program of video images through second tuner  12  that has a value indicated by its accompanying discretionary control data that is greater than the discretionary threshold.  
         [0050]    When a recording command is received by controller  34  from command input stage  32  for the same channel as is currently being received through the second tuner, the control voltage applied to the base of transistor Q 1  by terminal S 3  turns transistor Q 1  on so that AFT signals for second tuner  12  are shunted to either ground or to a local reference potential by the collector-emitter path of transistor Q 1  and the reception of that channel via second tuner  12  is blocked, thus locking the receiving operation of the multiple tuner appliance and thereby restricting reception to only those channels that are received through first tuner  10 . At the same time, during step  112  the AGC signals of the second tuner  12  are also blocked by third selector  28 , thereby preventing second tuner  12  from being used to receive any channel when the value of the discretionary control data carried by line  21  of a video image signal on that channel is greater than the discretionary threshold most recently stored in memory  30 . Therefore, it is impossible to record and view any program having discretionary control data that is greater in value than the discretionary threshold through the first and second tuners  10  and  12 .  
         [0051]    As described herein before, using the multi-tuner television receiving apparatus according to the preferred embodiment of the present invention, when the discretionary control data in the presently running program is greater than the discretionary threshold, not one tuner but also all of the other tuners in the video appliance are locked, whereupon the viewer is unable to view any program that parents deem inappropriate for young viewers. In addition, since transistor Q 1  blocks transmission of the AFT signals between controller  34  and second tuner  12  to lock operation of second tuner  12 , the operational program of the video appliance is substantially simplified.  
         [0052]    While the present invention has been described with respect to the particular embodiments, it will be apparent to those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the invention as defined in the following claims. By way of example, either the circuit illustrated by FIG. 1 or the circuit illustrated by FIG. 3 may be equipped with two selectors  14 ,  16 , and two transistors Q 1 , Q 2 , to be operationally coupled with a video signal appliance such as a second VCR, or a television, so that controller  34  may be used to simultaneously restrict video viewing and video signal recording by both appliances whenever the discretionary control data of a video program that is being selectively received by one of the tuners is greater than a discretionary threshold.