JPH08298634A - Television receiver for mobile object - Google Patents

Abstract

PURPOSE: To prevent the reproduced sound from being switched to the main sound due to a change in a receiving condition at the time of receiving sound multiplex broadcasting in a multi-path area or the like and reproducing sub- sound. CONSTITUTION: A sub-sound storing circuit 50 for forcedly selecting and outputting a sub-sound signal from a sound switching/matrix circuit 40 at the time of receiving a sub-sound storing signal regardless of the existence of a control signal is included in a sound multiplex demodulating circuit for a television(TV) tuner idependently of a sound discriminating/switching control circuit 48 for judging a sound state from a control signal superposed to a sound signal and controlling the circuit 40. Only at the time of executing timer reservation, the input of the sub-sound signal to the circuit 50 can be set up together with the setting of a receiving channel or the like. Consequently the sound to be reproduced can be prevented from being frequency switched between the sub-sound and the main sound due to the change in a receiving condition during the reserved reception, and at the time of normal reception, the generation of inaudibility due to switching of TV broadcasting from multi-sound broadcasting to monaural broadcasting can be prevented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mobile television receiver, and more particularly to a mobile television receiver suitable for demodulating a multiple audio signal including a main audio signal and a sub audio signal.

[0002]

2. Description of the Related Art Conventionally, in television broadcasting, audio is transmitted in any of monaural, stereo, and two audio, and a television receiving device side receiving this selects a television broadcasting signal of a desired channel. A voice signal is detected from the intermediate frequency signals obtained by localizing, and the control signal included in the voice signal is a stereo or two-voice multiple voice signal in which the voice signal is composed of a main voice signal and a sub-voice signal. It is determined whether there is a monaural audio signal containing only the main audio signal, and only the main audio signal is output according to the determination result, or the stereo audio composed of the left and right audio signals from the main audio signal and the sub audio signal. It controls whether to generate and output a signal or to select and output either the main audio signal or the sub audio signal.

By the way, of these television receivers,
In mobile TV receivers installed in automobiles, etc., it is easy to be affected by multipath distortion as the reception position changes, and from the detected audio signals during reception or reproduction of stereo or sub-audio. Sometimes the control signal representing the multiple audio signal cannot be detected, and the reproduced sound is switched from the stereo or sub audio to the monaural sound containing only the main audio.

On the other hand, in order to solve such a problem, conventionally, as disclosed in Japanese Patent Laid-Open No. 64-78034, if the multipath distortion is a predetermined value or less in a multipath area, auto separation is performed. It has been proposed to extend the time for enjoying the stereo reproduction sound without operating the control circuit.

[0005]

However, the proposed apparatus is intended to lengthen the time for generating a stereo audio signal by inserting the main audio signal and the sub audio signal into the matrix circuit, which is one of the two audio signals. The problem that the reception state deteriorates and the reproduced sound is switched to the main sound while reproducing the sub-audio cannot be improved at all.

That is, even if the reception state deteriorates during reception and reproduction of a stereo sound and the reproduced sound changes from a stereo sound to a monaural sound, only the stereo feeling is lost and the listening comfort is slightly lowered. , Broadcast contents can be continuously heard. However, when the sub signal of the two voices is being received and reproduced and the reception condition deteriorates and the control signal cannot be detected from the voice signal, the reproduced sound is in a language or broadcast different from that of the sub voice. Since it can be switched to the main voice of the content,
When the broadcast contents cannot be grasped and the main audio and the sub audio are frequently switched, it is very hard to hear and gives a great discomfort to the listener. However, the conventional television receiving device does not take any measures for the switching between the main audio and the sub audio, which frequently occurs in a multipath area where the reception state changes, and for a user who often hears the sub audio. , It was a very inconvenient receiver.

The present invention has been made in view of the above problems, and prevents the reproduced sound from being switched to the main sound due to the change in the receiving state during reception and reproduction of the sub-audio, thereby listening to the reproduced sound. The purpose is to eliminate the difficulty.

[0008]

The invention as set forth in claim 1 made in order to achieve the above object is a television set corresponding to a receiving channel designated from the outside, from a received signal inputted from a receiving antenna. Channel selecting means for selecting a broadcast signal and converting it to an intermediate frequency signal, audio signal detecting means for detecting an audio signal from the intermediate frequency signal, and selecting and outputting a main audio signal from the audio signal Main audio processing means, sub audio processing means for detecting and outputting a sub audio signal from the audio signal, and that the audio signal is a stereo audio or two audio multiplex audio signal from the audio signals. Control signal detecting means for detecting the control signal represented, and if the control signal is not detected by the control signal detecting means,
When the main audio signal from the main audio processing means is selected and output, and the control signal detecting means detects the control signal representing the stereo audio, the main audio signal and the sub audio from the main audio processing means. A stereo audio signal is generated and output from the sub audio signal from the processing means, and when a control signal representing two audios is detected by the control signal detection means, in response to a main / sub switching signal input from the outside. A television receiver for a mobile body, comprising: a voice switching control unit that selects and outputs either a main voice signal from the main voice processing unit or a sub voice signal from the sub voice processing unit. A sub voice holding command input means for inputting a sub voice holding command for forcibly selecting and outputting the sub voice signal from the voice switching control means by operation, and a sub voice holding command input means. When a command is input, a sub audio holding control that causes the audio switching control means to select and output the sub audio signal from the sub audio processing means regardless of the detection state of the control signal by the audio signal detection means. Means and are provided.

The invention described in claim 2 is the same as claim 1.
In the television receiver for a mobile object described in (1), as the sub audio holding command input means, in addition to the sub audio holding command, a timer reservation capable of inputting a reservation reception channel, a reservation reception start time, and a reservation reception end time, respectively. Reservation information storing means for storing each reservation information input from the timer reservation input means, time measuring means for measuring the current time, and current time measured by the time measuring means. Based on the reservation information stored in the reservation information storage means, the channel selection command corresponding to the reservation reception channel is selected from the time when the current time is the reservation reception start time to the time when the reservation reception end time is reached. Reservation reception control means for outputting to the station means to cause the selection means to select the television broadcast signal of the reservation reception channel, and further, the sub audio holding system. The means, when the tuning means selects the reserved reception channel and the reservation information storage means stores the sub audio holding command as the reservation information, regardless of the detection state of the control signal. The sub-audio signal is selected and output from the audio switching control means.

Next, the invention described in claim 3 is the television receiver for mobile body according to claim 2, wherein the timer reservation input means uses the reception channel, reception start time, and reception as the reservation information. An end time and encoded data obtained by encoding the sub voice holding command into a predetermined code are input, and the reservation information storage means decodes each reservation information from the input encoded data. It is characterized by storing.

[0011]

In the mobile television receiving apparatus according to the present invention, the channel selecting means is a television corresponding to the receiving channel designated from the outside, from the receiving signals input from the receiving antenna. The broadcast signal is selected and converted into an intermediate frequency signal, and the audio signal detection means detects an audio signal from the intermediate frequency signal. Then, the main audio processing means selects and outputs the main audio signal from the audio signals, and the sub audio processing means detects and outputs the sub audio signal from the audio signals.

[0012] In television broadcasting, the audio signal is a pair of main and sub-multiplexed audio signals obtained by synthesizing left and right stereo audio signals, or two audio signals of two types of audio, one main audio and the other sub audio. In the case of a multiple voice signal, the control signal representing each of these multiple voice signals is superposed on the voice signal, so the control signal detecting means detects the control signal from the voice signal, The voice switching control means, based on the detection state of the control signal by the control signal detection means,
Switches the audio signal output as the playback sound.

That is, the audio switching control means reproduces the main audio signal from the main audio processing means because only the main audio signal is present in the audio signal unless the control signal is detected by the control signal detection means. When a control signal representing stereo sound is detected by the control signal detection means, the left and right audio signals are output from the main audio signal from the main audio processing means and the sub audio signal from the sub audio processing means. When a control signal representing two voices is detected by the control signal detecting means, a main voice signal from the main voice processing means is generated according to the main / sub switching signal input from the outside. Or the sub audio signal from the sub audio processing means is selected as the audio signal for reproduction.

When an auxiliary voice holding command is input from the auxiliary voice holding command input means by an external operation, the sub voice holding control means detects the control signal by the voice signal detecting means with respect to the voice switching control means. Regardless of the state, the sub audio signal from the sub audio processing means is selected and output.

That is, in the mobile television receiving apparatus according to the first aspect, the user inputs a sub audio holding command as necessary, and the sub audio processing means detects the sub audio detected from the audio signal. An audio signal can be forcibly output. Therefore, according to the mobile television receiver,
Even under conditions where the reception state of the TV broadcast signal changes and the detection state of the control signal in the control signal detection means changes frequently, such as in a multipath area, the sub audio signal is forcibly output and the reproduced sound is reproduced. Can be prevented from frequently changing from the sub voice to the main voice. Therefore, even if noise is mixed in the reproduced sound (sub-audio) as the reception condition deteriorates, the user can continuously grasp the broadcast content,
For a user who often hears the sub-audio, the reception device is extremely convenient.

Next, in the mobile television receiving apparatus according to the second aspect of the present invention, in addition to the sub audio holding command, reservation is performed as a sub audio holding command input means for inputting the sub audio holding command by an external operation. There is provided timer reservation input means capable of respectively inputting a reception channel, a reservation reception start time, and a reservation reception end time. When each reservation information is input from this timer reservation input means, the reservation information storage means Reservation information is stored respectively.

Then, the reservation reception control means, based on the stored reservation information and the current time measured by the time counting means, until the reservation reception start time reaches the reservation reception end time. A channel selection command corresponding to the reserved reception channel is output to the channel selection means to cause the channel selection means to select the television broadcast signal of the reserved reception channel. Further, during this channel selection, if a sub audio holding command is stored as the reservation information in the reservation information storage means, the sub audio holding control means forcibly selects and outputs the sub audio signal to the audio switching control means. Let

That is, in the case where the sub audio holding command can be input at any time by operating the sub audio holding command input means, when the TV broadcasting is switched from the bi-audio broadcasting such as the bilingual broadcasting to the monaural broadcasting, the reproduced sound is reproduced. It is conceivable that the sub-audio will suddenly occur when the TV broadcasting is switched from the monaural broadcasting to the two-audio broadcasting if left unattended.

Therefore, in the mobile television receiving apparatus according to the second aspect, the sub audio holding command for forcibly outputting the sub audio signal from the audio switching control means can be input only when the timer is reserved. By doing so, these problems are solved. Therefore, according to the mobile television receiver of the second aspect, by performing timer reservation, it is possible to surely realize the sub-audio holding function only for a television broadcast in which two audio broadcasts are performed. , A more convenient TV receiver.

Further, in the mobile television receiving apparatus according to the present invention, the timer reservation input means predetermines a reception channel, a reception start time, a reception end time, and the sub audio holding command as reservation information. The coded data encoded into the code is input, and the reservation information storage means decodes and stores each reservation information from the input coded data.

Therefore, according to the television receiver for a mobile object of the third aspect, a bar code, a gem star code (so-called G code) or the like which is conventionally used for timer reservation in a video recorder or the like is used. As described above, the reservation information encoded by the arrangement of the bars, the numerical values, etc. can be input from the timer reservation input means, and the timer reservation can be made extremely easily.

[0022]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 3 is a block diagram showing the overall configuration of an on-vehicle audio / visual system (AV system) to which the present invention is applied.

As shown in FIG. 3, the AV system of this embodiment is provided with a television tuner (TV tuner) 1 as a television receiver, a display 52 for displaying an image, and a rear window of an automobile. Receiving antenna ANT and receiving antenna ANT including a glass antenna and a rod antenna for diversity reception
Amplifier 5 that amplifies and outputs the received signal from
4. A CD that stores map data for driving guidance
A CD-ROM player 56 for reading information from the ROM,
Radio receiver 5 for receiving AM / FM radio broadcasts
8, and a display computer 60 that is connected to each of these units via a bus 59 for bidirectional communication and centrally controls these units.

The display computer 60 receives signals from various sensors for detecting the operating state of the operating panel (that is, a command from the vehicle occupant) provided on the radio receiver 58 and the operating state of the vehicle (vehicle speed, brake operation, steering angle, etc.). This is for displaying on the display 52 a television image obtained by the TV tuner 1, image data such as map data read by the CD-ROM player 56, a message to a vehicle occupant, and the like in accordance with a vehicle signal. When the vehicle is stopped and the display of the television image is selected by the vehicle occupant, the received image is displayed on the display 52 by the video signal from the TV tuner 1.

On the other hand, the radio receiver 58 is capable of accommodating a plurality of compact discs (CDs) via a bidirectional communication bus 62, and a CD autochanger 64 for reading information from any CD and reproducing an audio signal. TV tuner 1, radio receiver 58, CD autochanger 6
Various audio devices, such as an audio amplifier 66 which receives various audio signals from 4 and the like, amplifies one of the audio signals and outputs the amplified audio signal to a speaker, are connected.

The radio receiver 58 is provided with an operation panel for the vehicle occupant to set the operation of the AV system as described above, and in accordance with the operation situation, switching of audio signals generated from the speaker, volume and sound quality. And the like. When the vehicle passenger selects the TV sound, the audio signal from the TV tuner 1 is output from the audio amplifier 66 to the speaker.

The information read from the CD by the CD autochanger 64 is sent to the CD-RO via the data bus 68.
It is input to the M player 56, and this information is further recorded on the CD-R.
The image data such as map data read by the OM player 56 is input to the display computer 60 via the data bus 69. Then, the display computer 60 causes the display 52 to display the input image data when the driving guide of the vehicle or the display of the CD information is selected.

Next, the TV tuner 1 performs data communication via the bus 59 as shown in FIG.
A microcomputer that executes various controls such as switching of reception channels and reservation reception according to various commands from a vehicle occupant input through an operation panel provided on the radio receiver 58 or a key input device 16 for remote control operation. (Microcomputer) 14, a reception unit 12 that selects a television broadcast signal of a reception channel designated by the microcomputer 14 from the reception signals input from the antenna amplifier 54 and demodulates a video signal and an audio signal, It is composed of a power supply circuit 18 which receives power supply from a battery mounted on a vehicle and supplies power to these respective parts. still,
The microcomputer 14 has a built-in clock for measuring the current time for receiving a reservation.

Then, the receiving section 12 generates a local oscillation signal having a frequency corresponding to the receiving channel designated by the microcomputer 14 side, and mixes the local oscillating signal with the receiving signal, so that the television of the receiving channel designated. Broadcast signal,
For example, a tuning circuit 2 as a tuning means for converting an intermediate frequency signal of video 58.75 MHz and audio 54.25 MHz.
An intermediate frequency amplification / detection circuit 4 that amplifies the intermediate frequency signal to detect a video signal, and an image amplification circuit 6 that amplifies the detected video signal and outputs the amplified video signal to the display 52.
And an audio detection circuit 8 as an audio signal detection means for detecting an audio signal (FM detection) from the intermediate frequency signals amplified by the intermediate frequency amplification / detection circuit 4, and from the detected audio signals. A pair of left and right audio signals for stereo broadcasting and main or sub audio signals for dual audio broadcasting, including the audio signals for monaural broadcasting, are output from the left and right speakers provided in the vehicle interior. The audio multiplex demodulation circuit 10 outputs the audio signals L and R.

Next, as shown in FIG. 2, in the audio multiplex demodulation circuit 10, the audio signal FM-detected by the audio detection circuit 8 is amplified by the amplification circuit 22, and the main audio signal (0 to 15 kHz) therein is amplified. ) Is a de-emphasis circuit 24 and a low-pass filter (LPF) 2 as main audio processing means.
It is input to the voice switching / matrix circuit 40 via 6. Of the audio signals amplified by the amplifier circuit 22, the sub-audio signal (16 kHz to 47 kHz) is a band-pass filter (BPF) 28, a limiter 30, a sub-audio FM detection circuit 32, a de-audio signal as a sub-audio processing means. It is input to the audio switching / matrix circuit 40 via the emphasis circuit 34 and the LPF 36. The de-emphasis circuit 2
Reference numerals 4 and 34 are for improving the SN ratio by flattening each audio signal, since each audio signal is emphasized at the broadcasting station side.

Next, during audio multiplex broadcasting (that is, during stereo broadcasting or dual audio broadcasting) in which the sub audio signal is superimposed on the audio signal FM-detected by the audio detection circuit 8, that effect is added to the audio signal. Control signal (55.125 kHz)
Are superimposed, the multiplex control AM detection circuit 42 and the limiter 44 are provided in the audio multiplex demodulation circuit 10 as control signal detection means for demodulating the control signal from the audio signal.
And a multi-control FM detection circuit 46.

The control signal after demodulation controls the voice switching / matrix circuit 40 by judging whether the voice signal received from this control signal is monaural, stereo, or two voices. Is output to the microcomputer 14 as voice information indicating the reception state. Upon receiving this audio information, the microcomputer 14 determines whether the currently received television broadcast is a monaural broadcast, a stereo broadcast, or a dual audio broadcast, and displays it on the operation panel or the like.

On the other hand, the voice switching / matrix circuit 40 is
Only the main audio signal is output as the left and right audio signals L and R, only the sub audio signal is output as the left and right audio signals L and R, or the main audio signal and the sub audio signal are input to the stereo matrix. The left and right stereo audio signals are reproduced, and the reproduced stereo audio signals are output as the left and right audio signals L and R as they are.

The voice switching / matrix circuit 4
The audio discrimination switching control circuit 48 for controlling 0 outputs only the main audio signal as the left and right audio signals L and R during monaural broadcasting. During stereo broadcasting, the stereo audio signal is usually reproduced from the main and sub audio signals, and the reproduced stereo audio signal is output as the left and right audio signals L and R respectively. However, a command from a vehicle occupant is received. Microcomputer 1
When the switching signal from 4 to monaural audio signal is input,
Similar to monaural broadcasting, only the main audio signal is output as left and right audio signals L and R. Also, during dual audio broadcasting, normally, only the main audio signal is output as the left and right audio signals L and R, as in the case of monaural broadcasting, but a switching signal from the microcomputer 14 to the sub audio signal is received in response to a command from the vehicle occupant. Is input, only the sub audio signal is the left and right audio signals L,
Output as R.

As described above, the voice discrimination switching control circuit 4
Reference numeral 8 determines whether the television broadcast is monaural broadcast, stereo broadcast, or dual audio broadcast based on the control signal superimposed on the audio signal, and controls the audio switching / matrix circuit 40 according to the determination result. However, among the signal lines connecting the voice discrimination switching control circuit 48 and the voice switching / matrix circuit 40, the voice discrimination switching control circuit 48 outputs a control signal for switching the output between the main voice signal and the sub voice signal. A sub-sound holding circuit 50 is provided on the signal line for doing so. When the sub voice holding circuit 50 receives the sub voice holding signal from the microcomputer 14, the voice discrimination switching control circuit 48.
Voice switching / matrix circuit 4 instead of the control signal from
A control signal for forcibly outputting the sub audio signal from 0 as the left and right audio signals L and R is input to the audio switching / matrix circuit 40 and corresponds to the sub audio holding control means of the present invention.

As a result, in the TV tuner 1 of the present embodiment, the reception condition of the television broadcast signal deteriorates in the multipath area and the like, and the two-voice broadcast is displayed even though the reception channel is the two-voice broadcast. Even if the control signal cannot be demodulated, if the sub-audio holding signal is input from the microcomputer 14 to the sub-audio holding circuit 50, the sub-audio signal is switched from the audio switching / matrix circuit 40 to the left and right audio signals L and R. Can be forced to output.

Next, a control process executed by the microcomputer 14 for the vehicle occupant to input the auxiliary voice holding signal from the microcomputer 14 to the auxiliary voice holding circuit 50 will be described. In this embodiment, the sub audio holding signal can be output from the microcomputer 14 only when the TV tuner 1 is operated for a predetermined time by so-called timer reservation. Therefore, in the following description, First, when the user operates the key input device 16 to make a timer reservation, the reception channel (C
H) The reservation process will be described, and then the reservation reception process executed by the microcomputer 14 to activate the receiving unit 12 according to the reservation content to receive the television broadcast signal of the reservation channel.

FIG. 4 is a flow chart showing the reception CH reservation process. In this reception CH reservation processing, the user operates the key input device 16 as timer reservation input means,
Start by inputting a reservation code composed of a numerical sequence of, for example, 0 to 9 that encodes the reception channel, reception start time, reception end time, and sub-voice holding information indicating whether or not to hold the sub-voice. To be done.

As shown in FIG. 4, when this process is started, first in S110 (S represents a step), the reservation code input from the key input device 16 is read, and S1
At 20, it is determined whether the read reservation code is normal. And if the reservation code is not normal,
In S130, a response message for causing the vehicle occupant to re-enter the reservation code is generated by voice, and S1
If the reservation code is normal, the process proceeds to S140, and a response message indicating that the reservation code has been normally read is generated by voice or the like, and the process proceeds to S150.
Move to

In step S150, from the read reservation code, the reception channel, reception start time, reception end time,
And the sub audio holding information is decoded, and in S160, each of the decoded reservation information is stored in the RAM as a reservation information storage unit.
To be stored. Then, after storing this reservation information, S17
At 0, the power supply from the power supply circuit 18 to the receiver 12 is cut off (power off) to stop the operation of the receiver 12,
The process ends.

Next, FIG. 5 is a flow chart showing the reservation reception process as the reservation reception control means. The reservation receiving process is executed when the reservation information is stored in the RAM by the reception CH reservation process. As shown in FIG. 5, when this process is started, first, in S210, the current time is read from the built-in clock as the time counting means, and R is read.
It waits until the reception start time is reached by determining whether or not the reception start time stored in the AM has come.

At the reception start time, S220
Then, the power supply from the power supply circuit 18 to the reception unit 12 is started (power supply is turned on), and the RA for the tuning circuit 2 of the reception unit 12 is
The reception channel (CH) stored in M is set, the television broadcast signal of this channel is tuned in, and in S240, the sub audio holding information is read from the RAM to determine whether or not the sub audio holding is necessary. . If it is not necessary to hold the sub-voice, a voice switching reference signal for causing the voice discrimination switching control circuit 48 to execute a normal operation is output in S250, and S
If it is necessary to hold the sub-voice, the process proceeds to S2.
At 60, a process as a sub voice holding command input means for outputting a sub voice holding signal to the sub voice holding circuit 50 is executed, and S
Move to 270.

Next, in S270, the present time is read from the built-in clock and it is judged whether or not the reception end time stored in the RAM has come to wait until the reception end time is reached. Then, when the reception end time comes, in S280, the power supply from the power supply circuit 18 to the reception unit 12 is cut off (power supply OFF), and the process ends.

As described above, in the TV tuner 1 of this embodiment, by providing the sub audio holding circuit 50 in the audio multiplex demodulation circuit 12, when the control signal representing the two audio broadcast cannot be detected from the audio signal. However, the audio switching / matrix circuit 40 is configured to forcibly output the sub audio signal, and the compulsory output (holding the sub audio) of the sub audio signal is performed by so-called timer reservation. It can be executed only when the TV tuner 1 is operated from a preset reception start time to a reception end time.

Therefore, according to the TV tuner 1 of the present embodiment, the reception state of the television broadcast signal changes in a multipath area or the like, and a control signal indicating that the reception channel is a two-voice broadcast. Even if it becomes impossible to demodulate, the sub audio signal can be forcibly reproduced during the period when the timer-reserved receiving channel is reserved and received, and the reproduced sound is between the sub audio and the main audio. It is possible to prevent frequent switching. Therefore, even if noise is mixed in the reproduced sound (sub audio) due to the deterioration of the reception state, the vehicle occupant can continuously grasp the broadcast content and often hear the sub audio. It will be a very easy-to-use TV tuner for users.

Further, the sub-audio hold can be set only at the time of reservation reception, and at the time of normal reception, the audio is reproduced according to the control signal in the audio signal, so that it is possible to perform the two-audio broadcast on the television broadcasting. It becomes possible to execute sub audio retention only, and during normal reception, the TV broadcast switches from dual audio broadcast to monaural broadcast, and no sound can be heard.
It is possible to prevent sudden occurrence of sub-audio from the speaker when the television broadcasting is switched from the monaural broadcasting to the two-audio broadcasting.

Further, since various reservation information can be set by a preset reservation code and it is not necessary to sequentially input the receiving channel, the reception start / end time, etc., even if the vehicle driver is the vehicle Settings can be made in a short time during suspension, and mistaken input of reservation information can be prevented.

Although one embodiment of the present invention has been described above, the present invention is not limited to this embodiment and can take various forms. For example, in the present embodiment, the T that is formed separately from the display 52, the audio amplifier 66, etc. as a part of the vehicle-mounted AV system.
Although the V tuner 1 has been described, the present invention is not limited to the above, as long as it is a television receiver that is integrally configured with a display, a speaker, and in some cases, a television antenna, as long as it is a television receiver compatible with audio multiplex broadcasting. It can be applied similarly to the embodiment. Further, the present invention is also applicable to a television receiver dedicated to an audio signal, which demodulates an audio signal of a television broadcast and does not demodulate a video signal with or without an audio signal of AM / FM radio broadcast. It can be applied similarly to the embodiment.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a TV tuner according to an embodiment.

FIG. 2 is a block diagram showing a configuration of an audio multiplex demodulation circuit 10 provided in a TV tuner.

FIG. 3 is a block diagram showing a configuration of an entire vehicle-mounted AV system provided with a TV tuner.

FIG. 4 is a flowchart showing a reception CH reservation process executed in a microcomputer of a TV tuner.

FIG. 5 is a flowchart showing a reservation receiving process similarly executed in the microcomputer.

[Explanation of symbols]

1 ... TV tuner 2 ... Channel selection circuit 4 ... Intermediate frequency amplification / detection circuit 6 ... Video amplification circuit 8 ... Sound detection circuit 10 ... Sound multiplex demodulation circuit 12 ... Reception unit 14 ... Microcomputer 16 ... Key input device 18 ... Power supply circuit 22 … Amplifier circuit 24… De-emphasis circuit 2
6, 36 ... LPF 28 ... BPF 30, 44 ... Limiter 32 ... Sub audio FM detection circuit 40 ... Audio switching / matrix circuit 42 ... Multiple control F
M detection circuit 46 ... Multiplex control FM detection circuit 48 ... Voice discrimination switching control circuit 50 ... Sub voice holding circuit 52 ... Display 54
… Antenna amplifier ANT… Receiving antenna 66… Audio amplifier

Claims (3)

[Claims] 1. A tuning unit for selecting a television broadcast signal corresponding to a receiving channel designated from the outside from a received signal input from a receiving antenna and converting the selected signal into an intermediate frequency signal, and the intermediate frequency signal. An audio signal detecting means for detecting an audio signal from the inside, a main audio processing means for selecting and outputting a main audio signal from the audio signal, and a sub-output for detecting and outputting a sub audio signal from the audio signal. An audio processing means; a control signal detecting means for detecting a control signal indicating that the audio signal is a stereo audio or a multiple audio signal of two audios from the audio signal; and the control signal by the control signal detecting means. Is not detected, the main audio signal from the main audio processing means is selected and output, and when the control signal representing stereo sound is detected by the control signal detection means, the main audio processing means From the main audio signal from the sub audio processing means and the sub audio signal from the sub audio processing means, and outputs the stereo audio signal. When the control signal detecting means detects a control signal representing two sounds, it is input from the outside. Audio switching control means for selecting and outputting either the main audio signal from the main audio processing means or the sub audio signal from the sub audio processing means in accordance with the generated main / sub switching signal. In a television receiver for a mobile body, a sub audio holding command input means for inputting a sub audio holding command for forcibly selecting and outputting the sub audio signal from the audio switching control means by an external operation, and the sub audio holding command. When the sub voice holding command is input from the holding command inputting means, the voice switching control means is controlled by the sub voice processing means regardless of the detection state of the control signal by the voice signal detecting means. Mobile television receiver is characterized by providing a sub-audio holding control means for selectively outputting an audio signal. 2. The auxiliary voice holding command input means includes timer reservation input means capable of inputting a reserved reception channel, a reservation reception start time, and a reservation reception end time in addition to the sub voice holding command. Reservation information storage means for storing each of the reservation information input from the timer reservation input means, time clock means for clocking the current time, current time clocked by the time clock means, and the reservation information storage means Based on the stored reservation information, outputs a channel selection command corresponding to the reservation reception channel to the channel selection means from the time when the current time is the reservation reception start time to the time when the reservation reception end time is reached. Reservation reception control means for causing the channel selection means to select the television broadcast signal of the reserved reception channel, and the sub audio holding control means includes the channel selection means. When the reserved reception channel is selected and the sub audio holding command is stored as the reservation information in the reservation information storage means, the sub switching from the audio switching control means regardless of the detection state of the control signal. The mobile television receiving apparatus according to claim 1, wherein an audio signal is selected and output. 3. The timer reservation input means is configured to input, as the reservation information, a reception channel, a reception start time, a reception end time, and encoded data obtained by encoding the sub audio holding command into a predetermined code. The mobile television receiving apparatus according to claim 2, wherein the reservation information storage unit decodes and stores each of the reservation information from the input encoded data.