JPH07226886A - On-vehicle television receiver - Google Patents

Abstract

PURPOSE:To attain the channel selection of sound by using as in the conventional manner in the area of strong electric field intensity and effectively utilizing the function of presetting a receiving frequency in the area of weak intensity. CONSTITUTION:Only broadcasting wave of electric intensity which is strong enough to satisfactorily receive both video and sound is stored in a preset memory 22. A microcomputer 2 sets a reference signal level to be the reference of comparing to be the reference signal level of a high level to conduct automatic preset operation. To put it in the concrete, the radio wave from an antenna 11 is set to be a reception frequency specified by a tuner part 12 and introduced to a wave-detector and decoder 13, and its received signal level is sent to the microcomputer 2. The microcomputer 2 compares the received signal level with the set reference signal level of the high level and when the received signal level is higher, the reception frequency is stored in the memory 22 so as to Sweep the reception frequency again. In the above-mentioned manner, all the reception frequencies are successively compared and only the broadcasting wave with the received signal level higher than the reference signal level is stored in the memory 22.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a television receiver having a preset function for storing a specific reception frequency in advance, and more particularly, it cannot be preset because the electric field strength is lower than a reference signal level required for presetting. At times, the present invention relates to a vehicle-mounted television receiver capable of presetting a reception frequency with which sound is reproduced well even when the electric field strength is low.

[0002]

2. Description of the Related Art In a vehicle-mounted television receiver, a reception frequency with a high electric field strength capable of receiving a good image is stored in a memory (hereinafter referred to as a preset) in advance so that the reception frequency can be easily selected and used. Sometimes, a preset method is adopted in which a desired reception frequency can be selectively received by a one-touch operation of a push button switch or the like.

FIG. 7 is a block diagram showing the structure of a conventional vehicle-mounted television receiver. Hereinafter, description will be given with reference to the drawings. 6
Is a detection demodulation unit that detects and demodulates the received radio wave. An antenna 61 that receives the radio wave, a tuner unit 62 that selectively receives the broadcast wave of a specific frequency, and a detection demodulator 63 that detects and demodulates the selected broadcast wave. Composed. The reception signal level (electric field strength of the received radio wave) from the tuner unit 62 is sent to the microcomputer 7. Reference numeral 7 denotes a microcomputer, which sends a reception frequency instruction signal for instructing the reception frequency to the detection demodulation unit 6, and receives the reception signal level sent from the tuner unit 62 and a preset reference signal level (normally a good image is obtained. (Set to the lowest field strength required). Reference numeral 8 denotes a display unit for displaying an image, which includes an image amplifier 81 for amplifying the image signal separated from the detection demodulator 63, and a display 82 such as a liquid crystal for displaying. Reference numeral 9 denotes an audio unit for reproducing sound, which is composed of a sound amplifier 91 for amplifying the sound signal separated from the detection demodulator 63 and a speaker 92 for reproducing sound.

Further, a preset switch 71 and a preset memory 72 are connected to the microcomputer 7, and when the preset switch 71 is operated, the corresponding preset memory 72
The frequency of the broadcast wave stored in is called and is sent to the detection demodulator 6 as a reception frequency signal. And 7
Reference numeral 0 is an auto preset switch for activating an auto preset operation, which will be described later, for automatically storing the frequency in the preset memory 72.

Next, a method of storing the frequency of the broadcast wave in the preset memory 72 will be described. In the auto-preset method, when the auto-preset switch 70 is operated, the reception frequency (1-62 ch) is received based on the instruction from the microcomputer 7.
Are sequentially scanned, the detected and demodulated reception signal levels of the respective reception frequencies are compared with the reference signal level preset in the microcomputer 7, and if the reception signal level is higher, the reception frequency is stored in the preset memory 72. be registered. If the received signal level is lower, a good image cannot be obtained, so the received frequency is not stored in the preset memory 72. In this way, the received signal level and the reference signal level of the broadcast waves of all the received frequencies are sequentially compared, and only the frequency of the broadcast wave having the received signal level higher than the reference signal level is automatically preset memory 72.
Memorized in.

The number of preset switches 71 varies depending on the device, but normally there are 6 to 10, and the viewer can watch the video / audio of the broadcast wave of the reception frequency corresponding to the switch only by pressing the preset switch. it can. Incidentally, in the auto preset, the preset order is usually from the low reception frequency to the high reception frequency, but if the manual preset is used together, the reception frequency can be selected. However, in both cases, only the reception frequency whose reception signal level is higher than the reference signal level is stored in the preset memory 72.

[0007]

Although it is unavoidable that a good image cannot be displayed because the electric field strength is weak, there are cases where it is desired to hear only the voice even if the image cannot be seen. In general broadcasting, good audio is often obtained even if good video is not obtained. Even in such a case, if the received signal level is compared with the reference signal level necessary for obtaining a good image as in the conventional case and auto preset is performed, the image quality is poor but the sound can be heard well. There is a problem that I cannot remember. Further, in an area where the electric field strength is weak, there is almost no reception frequency stored in the preset memory 72, and there is a problem that the auto preset function is useless.

An object of the present invention is to solve such a problem, and an object thereof is to enable a preset memory to store the reception frequency of a broadcast wave in which audio can be heard even when an image is not seen.

[0009]

In order to achieve the above object, the present invention stores a plurality of preset memories for storing the reception frequency of television broadcasting and a preset memory corresponding to the preset switch when the preset switch is operated. Preset reception means for receiving a broadcasting station of the specified reception frequency, sweeping the reception frequency of the television broadcasting, comparing the reception signal level from the tuner section with the reference signal level, and receiving the signal higher than the reference signal level. In a vehicle-mounted television receiver equipped with an auto-preset means for sequentially storing the reception frequency having a signal level in advance in correspondence with a preset switch, a state detection means for detecting the state of the display section and a state detection means for detecting the state of the display section The reference signal level is the first reference signal necessary for reproducing a good image. Level, or is characterized in that it comprises good signal level setting means for setting a second reference signal level required to reproduce the sound, the.

Preferably, the state detecting means detects an open / closed state of the display section, and the state detecting means detects a connection or cutoff state of a video signal of the display section. Is something
Alternatively, in the case where the display unit is a liquid crystal display, the state detecting means detects whether the backlight of the liquid crystal display unit is on or off.

Further, a plurality of preset memories for storing the reception frequency of the television broadcast, and a preset receiving means for receiving the broadcasting station of the reception frequency stored in the preset memory corresponding to the preset switch when the preset switch is operated, In an on-vehicle TV receiver equipped with, a receiving frequency sweeping means for sweeping the receiving frequency of TV broadcasting in the tuner section, a received signal level from the tuner section at the time of receiving frequency sweep, and necessary for reproducing good video A first signal level comparison means for comparing the first reference signal level with the first reference signal level, the received signal level from the tuner section, and a second signal level required for reproducing good sound.
The second signal level comparing means for comparing the received signal level with the first reference signal level higher than the first reference signal level according to the comparison result of the first signal level comparing means. The first memory group for storing the preset switch, and the reception frequency having the reception signal level higher than the second reference signal level according to the comparison result of the second signal level comparison means, It is characterized by further comprising a second memory group for storing the preset switch and a selecting means for selecting the first memory or the second memory as the preset memory according to the state of the display unit. It is a thing.

Preferably, the state detecting means detects an open / closed state of the display section, and the state detecting means detects a connection or interruption state of a video signal of the display section. Is something
Alternatively, in the case where the display unit is a liquid crystal display, the state detecting means detects whether the backlight of the liquid crystal display unit is on or off.

[0013]

In general television broadcasting, good audio is often obtained even if good video is not obtained. That is, the received signal level required to obtain good sound is
Lower than the received signal level required to get a good picture. If the state detecting means detects the state of the display unit and the display unit is in a receivable state, the first signal necessary for obtaining the received signal level from the tuner unit and a good image.
The reference signal level is compared by the comparison means and stored in the preset memory. Further, if the state detecting means detects the state of the display unit and the display unit is in the unreceivable state, the received signal level from the tuner unit and the second reference signal level necessary for obtaining good sound are set. The comparison means compares and is stored in the preset memory. as a result,
During reception and reproduction, the display is made receivable in a broadcast wave having a high electric field strength that allows good reception of video, and video and audio are reproduced with one touch. Also, in the case of a broadcast wave having a weak electric field strength such that an image cannot be properly received, the display is made unreceivable and only the sound is reproduced by one touch.

If the state detecting means detects the state of the display unit and the display unit is in a receivable state,
The comparison means compares the received signal level from the tuner section with the first reference signal level required to obtain a good image, and the result is stored in the first preset memory group. Further, if the state detecting means detects the state of the display unit and the display unit is in the unreceivable state, the received signal level from the tuner unit and the second reference signal level necessary for obtaining good sound are set. The comparison means compares and is stored in the second preset memory group. As a result, at the time of reception / reproduction, the first or second preset memory group is selected according to the state of the display unit (that is, whether both video and audio are reproduced or only audio is reproduced).

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a block diagram showing the configuration of a vehicle-mounted television receiver according to an embodiment of the present invention. Hereinafter, description will be given with reference to the drawings. Reference numeral 1 is a detection demodulation unit that detects and demodulates the received radio wave, including an antenna 11 that receives the radio wave, a tuner unit 12 that selectively receives a broadcast wave of a specific frequency, and a detection demodulator 13 that detects and demodulates the selected broadcast wave. Composed of. The reception signal level (received electric field strength) from the tuner unit 12 is sent to the microcomputer 2. 2 is a microcomputer, which is a detection demodulation unit 1
A reception frequency instruction signal for instructing the reception frequency is sent to the receiver, and the reception signal level sent from the tuner unit 12 is compared with a preset reference signal level. Also,
The microcomputer 2 selects whether or not to display an image depending on the operation state of the operator, and opens the stored display 32 (displays the screen) or closes it (stores the screen).
The display 32 is instructed as to whether or not to set the state.

Reference numeral 3 denotes a display unit for displaying a video, which is composed of a video amplifier 31 for amplifying the video signal separated from the detection demodulator 13, and a display 32 such as a liquid crystal for displaying. Reference numeral 4 is an audio unit for reproducing voice, and is an audio amplifier 4 for amplifying the audio signal separated from the detection demodulator 13.
1. The speaker 42 reproduces voice. Also,
A preset switch 21 and a preset memory 22 are connected to the microcomputer 2, and when the preset switch 21 is operated, the frequency of the broadcast wave stored in the corresponding preset memory 22 is called and sent to the detection demodulator 1 as a reception frequency signal. It Reference numeral 20 denotes an auto preset switch for activating an auto preset operation, which will be described later, for automatically storing the frequency in the preset memory 22.

FIG. 2 is a flowchart showing an auto preset process executed by the microcomputer 2. This process is started when the auto preset switch 20 is operated. In step A1, it is determined whether the display 32 is in the open state or the closed state. If the display state is the open state, the process proceeds to step A2, and if the display state is the closed state, the process proceeds to step A4. In this judgment, the microcomputer 2 originally controls the display 32 in response to a switch operation to open or close the display 32. Therefore, this control state is stored in the memory and Can be performed from the control state stored in. The state of the display 32 can be detected by using a switch, an optical sensor, or the like that works in conjunction with the movement of the display 32. If it is open, the display 32 is in a state where it can be displayed on the front and display an image, and if it is closed, the display 32 is stored in the device.

At step A2, the level is set to the first reference signal level (high S1 level). In other words, this means that only the broadcast wave having a strong electric field strength so that both video and audio can be received well is stored in the preset memory 22, and the microcomputer 2 sets the reference signal level serving as the reference for comparison to the first reference signal level. Set to (high S1 level). At step A3, the auto preset operation is executed at the first reference signal level (high S1 level), and the process is ended. To explain this process in a little more detail, the antenna 1
A specific reception frequency of the radio wave received at 1 is selected by the tuner unit 12 and introduced into the detection / demodulator 13. The detected and demodulated received signal level is sent to the microcomputer 2. If the received signal level is higher than the preset first reference signal level (high S1 level), the microcomputer 2 stores the received frequency in the preset memory 22 and sweeps the received frequency again. To do. If the received signal level is lower, the received frequency is not stored in the preset memory 22 and the received frequency is swept again. In this way, all reception frequencies (1-62ch) are sequentially compared,
Only the broadcast wave having the received signal level higher than the reference signal level is stored in the preset memory 22. In this way, the reception frequency at which both video and audio can be received well is stored in the preset memory 22. The microcomputer 2
The display is in an open state according to the instruction, and the viewer can directly check the image reception state on the display 32.

At step A4, the level is set to the second reference signal level (low S2 level). In other words, it means that the reception frequency of a weak electric field strength that can receive good sound but not good sound is also stored in the preset memory 22, and the reference signal level as the reference for comparison is set to the second reference signal. Set to level (low S2 level).

At step A5, the auto preset operation is executed at the second reference signal level (low S2 level), and the process is completed. The details are the same as in step A3, and therefore will be omitted. In this way, the reception frequency of the reception signal level higher than the second reference signal level (low S2 level) is also stored in the preset memory 22. When the number of broadcast waves to be stored reaches the maximum number that can be stored in the preset memory 22, the auto preset operation ends at that point (step A3, step A5).

From the above, the frequency of a broadcast wave having a strong electric field strength so that both video and audio can be received well, and the frequency of a broadcast wave having a weak electric field strength such that good video cannot be received but good audio can be received. Storage processing of both frequencies in the preset memory 22 is performed according to the open / close state of the display 32. Next, a method for the viewer to use the vehicle-mounted television having the preset function according to the embodiment of the present invention will be described.

FIG. 3 is a flow chart showing a preset reception process executed by the microcomputer 2. This process is started when the viewer operates the preset switch 21.
In step B1, the frequency of the broadcast wave stored in the preset memory 22 corresponding to the preset switch operated by the viewer is read and sent to the detection demodulator 1 as a reception frequency instruction signal.

In step B2, the microcomputer 2 executes the auto-preset with the selected preset switch in the state where the display 32 is open (state of step A3).
It is determined whether or not the auto preset is executed in the closed state (state of step A5). Display 3
If the auto-preset is executed in the open state of step 2, the process proceeds to step B3. If the auto-preset is executed in the closed state, the process proceeds to step B5.

At step B3, the microcomputer 2 opens the display 32 and moves to step B4. Then, in step B4, the video and audio of the reception frequency corresponding to the selected preset switch are reproduced, and the processing ends. Further, in step B5, the microcomputer 2 closes the display 32 and moves to step B6. And
At step B6, only the sound of the reception frequency corresponding to the selected preset switch is reproduced and the process is completed.

Although it is possible to display the image when only the voice is reproduced by performing the processing from step B3 by operating a switch (not shown), a good image cannot be expected in this case. On the contrary, it is also possible to erase the video while both video and audio are being reproduced by performing the processing from step B5 by operating a switch (not shown).

Further, in this embodiment, the microcomputer 2 instructs the display 32 to open and close, so that the display 32 operates to open and close, and the received signal level is compared with a high reference signal level to preset memory. It is decided whether to memorize in 22 or compare with a low reference signal level and preset. However, the display 32 is opened and closed manually,
The state may be detected and controlled by a contact switch, an optical sensor, or the like.

In a television receiver of the type in which the display 32 is always exposed, the microcomputer 2 opens the display 32 during presetting and reception / reproduction.
Instead of closing, the video signal should be connected or shut off, and in the case of a liquid crystal display, the backlight should be turned on or off. As described in detail above, according to the present embodiment, the microcomputer automatically changes the reference signal level for auto-preset by judging the open / closed state of the display, and the viewer can only listen to the sound. You can listen to various broadcast waves just by operating the preset switch.

FIG. 4 is a block diagram showing the configuration of a vehicle-mounted television receiver according to the second embodiment of the present invention. Hereinafter, description will be given with reference to the drawings. Reference numeral 1 is a detection demodulation unit that detects and demodulates the received radio wave, including an antenna 11 that receives the radio wave, a tuner unit 12 that selectively receives a broadcast wave of a specific frequency, and a detection demodulator 13 that detects and demodulates the selected broadcast wave. Composed of. The reception signal level (received electric field strength) from the tuner unit 12 is sent to the microcomputer 2. Reference numeral 2 denotes a microcomputer, which sends a reception frequency instruction signal for instructing the reception frequency to the detection demodulation unit 1 and compares the reception signal level sent from the tuner unit 12 with a preset reference signal level.
In addition, the display unit of the microcomputer 2 is in an open (screen display) state or closed (screen storage).
The preset memory 22a or 22b is selected by receiving a signal from a detector 33 such as a contact switch for detecting whether the preset memory 22a or 22b is in the state.

Reference numeral 3 denotes a display unit for displaying an image, which is an image amplifier 31 for amplifying the image signal separated from the detection demodulator 13, a display 32 such as a liquid crystal for displaying, and a display unit in an open (screen display) state. It is composed of a detector 33 such as a contact switch for detecting whether it is in the open state or in the closed (screen storage) state. Four
Is an audio unit for reproducing voice, and is composed of a voice amplifier 41 for amplifying the voice signal separated from the detection demodulator 13, and a speaker 42 for reproducing voice.

Further, a preset switch 21 and two preset memories 22a and 22b are connected to the microcomputer 2, the preset memory 22a or 22b is selected according to the output of the detector 33 of the display unit 3, and the preset switch 21 is further selected. When is operated, the frequency of the broadcast wave stored in the corresponding preset memory 22a or 22b is called and sent to the detection demodulator 1 as a reception frequency signal. 20 is a preset memory 22
It is an auto preset switch for activating an auto preset operation, which will be described later, for automatically storing the frequency in a or 22b.

FIG. 5 is a flow chart showing the auto preset process executed by the microcomputer 2 of the second embodiment.
The present embodiment is a method in which there are two systems of a preset memory group which is stored in the preset memory when the electric field strength is strong and a preset memory group which is stored in the preset memory when the electric field strength is weak, and they are separately stored in the preset memory.

This process is started when the auto preset switch 20 is operated. In step C1, it is determined whether the display 32 is in the open state or the closed state, and if it is in the open state, the process proceeds to step C2, and if it is in the closed state, the process proceeds to step C3. In this judgment, the state of the display 32 can be known from the output of the detector 33 of the display unit 3. That is, the detector 33 is composed of, for example, a contact switch, and the display 3
When 2 is stored and the contact switch is pressed, a close signal is output, and when the display 32 is displayed and the contact switch is opened, an open signal is output. There is also a method of detecting whether or not the display 32 blocks the optical path using an optical sensor or the like.

In step C2, the level is set to the first reference signal level (high S1 level). That is, this means that only the reception frequency having a strong electric field strength so that both video and audio can be received well is stored in the preset memory 22a, and the microcomputer 2 sets the reference signal level serving as the reference for comparison to the first reference signal level. Set to (high S1 level).

At step C3, the preset memory group is designated as the group (22a). That is, instructing to store the result of comparing the received signal level and the first reference signal level in the preset memory of the preset memory group (22a) below. At Step C4, the auto preset operation is executed at the first reference signal level (high S1 level), and the process is completed. To explain this processing in more detail, the radio wave received by the antenna 11 is transmitted to the tuner unit 1.
A specific reception frequency is selected at 2 and introduced to the detection / demodulator 13. The detected and demodulated received signal level is sent to the microcomputer 2. If the received signal level is higher than the preset first reference signal level (high S1 level), the microcomputer 2 stores the received frequency in the preset memory 22a, and sweeps the received frequency again. To do.
If the received signal level is lower, the received frequency is not stored in the preset memory 22a and the received frequency is swept again. In this way, all reception frequencies (1-62
ch) are sequentially compared, and only the reception frequency having the reception signal level higher than the reference signal level is stored in the preset memory 22.
Store in a. In this way, the reception frequency that enables good reception of both video and audio is the preset memory 22a.
Memorized in. It should be noted that the display is in an open state, and the viewer can display the video reception state on the display 32.
You can check directly with.

In step C5, the level is set to the second reference signal level (low S2 level). In other words, the preset memory 22b has a reception frequency with a weak electric field intensity that can receive good audio but cannot receive good audio.
The second reference signal level (low S2 level) is set as the reference signal level serving as a reference for comparison.

At step C6, the preset memory group is designated as the group (22b). That is, instructing to store the result of comparison between the received signal level and the second reference signal level in the preset memory of the preset memory group (22b) below. At Step C7, the auto preset operation is executed at the second reference signal level (low S2 level), and the process is terminated. The details are the same as in the case of step C4 described above, and will be omitted. In this way, the reception frequency of the reception signal level higher than the second reference signal level (low S2 level) is also stored in the preset memory 22b. The number of broadcast waves to be stored is the preset memory 22.
When the maximum number that can be stored in b is reached, the auto preset operation is terminated at that point (step C4, step C4).
7).

As described above, the reception frequency is so strong that electric field strength is strong enough to receive both video and audio, and the frequency of a broadcast wave whose electric field strength is weak enough that good video cannot be received but good audio can be received. Both preset memories 22
The storage processing to the a and 22b is performed according to the open state and the closed state of the display 32. Next, a method for the viewer to use the vehicle-mounted television having the preset function according to the embodiment of the present invention will be described.

FIG. 6 is a flow chart showing the preset reception process executed by the microcomputer 2. This process is started when the viewer operates the preset switch 21.
In step D1, the microcomputer 2 determines from the output of the detector 33 whether the display 32 is in the open state or the closed state. If it is open, go to step D2. If it is closed, go to step D3.
Move to.

At step D2, the microcomputer 2 designates the preset memory group (22a), and then proceeds to step D4. Further, in step D3, the microcomputer 2 designates the preset memory group (22b), and then proceeds to step D4.
In step D4, the frequency of the broadcast wave stored in the portion corresponding to the preset switch operated by the viewer is read out from the preset memory group (22a) or the preset memory group (22b) designated in step D2 or step D3. Then, the signal is sent to the detection / demodulation unit 1 as a reception frequency instruction signal, and the image and sound (in the case of display open) or sound (in the case of display closed) of the reception frequency corresponding to the selected preset switch are reproduced and the processing is finished.

Although it is possible to display the image when only the sound is reproduced by performing the processing from step B3 by operating a switch (not shown), a good image cannot be expected in this case. On the contrary, it is also possible to erase the video while both video and audio are being reproduced by performing the processing from step B5 by operating a switch (not shown).

According to the present embodiment, even if the preset memory has a margin due to the layout limitation of the device, the preset number is limited by the number of switches (generally push buttons) provided on the front panel (problem in area). When the number of switches cannot be increased, there is an advantage that the number of broadcast waves that can be easily stored in the preset memory can be increased by having two preset memory groups.

[0042]

As described above in detail, according to the present invention, the same usage as in the conventional method can be performed in the area where the electric field strength is strong, and the voice channel can be easily selected in the area where the electric field strength is weak. In addition, the number of broadcast waves that can be stored in the preset memory can be increased, and the preset function can be effectively used.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a vehicle-mounted television receiver according to an embodiment of the present invention.

FIG. 2 is a flowchart showing an auto preset process executed by a microcomputer according to an embodiment of the present invention.

FIG. 3 is a flowchart showing a preset reception process executed by a microcomputer according to an embodiment of the present invention.

FIG. 4 is a block diagram showing a configuration of a vehicle-mounted television receiver according to a second embodiment of the present invention.

FIG. 5 is a flowchart showing an auto preset process executed by a microcomputer according to the second embodiment of the present invention.

FIG. 6 is a flowchart showing preset reception processing executed by a microcomputer according to the second embodiment of the present invention.

FIG. 7 is a block diagram showing a configuration of a conventional vehicle-mounted television receiver.

[Explanation of symbols]

 1 ... Detection and demodulation unit 2 ... Microcomputer 3 ... Display unit 4 ... Audio unit

Claims (8)

[Claims] 1. A plurality of preset memories for storing reception frequencies of television broadcasts, and preset receiving means for receiving a broadcasting station having a reception frequency stored in a preset memory corresponding to the preset switches when the preset switch is operated. , Sweeping the reception frequency of the television broadcasting, comparing the reception signal level from the tuner unit with the reference signal level, and corresponding the reception frequency having the reception signal level higher than the reference signal level to the preset switch in advance. In order to reproduce a good image with the reference signal level according to the state detection means for detecting the state of the display part and the state of the display part, in a vehicle-mounted television receiver having an auto preset means for sequentially storing 1st reference signal level required for, or needed to play good audio Car TV receiver, characterized in that it includes a signal level setting means for setting a second reference signal level, the. 2. The vehicle-mounted television receiver according to claim 1, wherein the state detecting means detects an open / closed state of the display section. 3. The vehicle-mounted television receiver according to claim 1, wherein the state detecting means detects a connection or disconnection state of a video signal of the display section. 4. The display unit is in a state in which a backlight is turned on or off when the display unit is a liquid crystal display.
The vehicle-mounted television receiver described. 5. A plurality of preset memories for storing reception frequencies of television broadcasts, and preset receiving means for receiving a broadcasting station of a reception frequency stored in a preset memory corresponding to the preset switches when the preset switch is operated. In order to reproduce a good video, in the in-vehicle TV receiver equipped with, the receiving frequency sweeping means for sweeping the receiving frequency of the TV broadcast in the tuner section, the received signal level from the tuner section at the time of the receiving frequency sweep First signal level comparing means for comparing with a necessary first reference signal level, the received signal level from the tuner section at the time of receiving frequency sweep, and a second reference necessary for reproducing good voice Second signal level comparing means for comparing the signal level with the first signal level comparing means In response to the comparison result of the first memory group for storing the reception frequency having the reception signal level higher than the first reference signal level in association with the preset switch, the comparison result of the second signal level comparison means. And a second memory group for storing the reception frequency having the reception signal level higher than the second reference signal level in association with the preset switch, and the first memory or the first memory according to the state of the display unit. A vehicle-mounted television receiver, comprising: a selection unit that selects two memories as the preset memory. 6. The vehicle-mounted television receiver according to claim 5, wherein the state detecting means detects an open / closed state of the display section. 7. The vehicle-mounted television receiver according to claim 5, wherein the state detecting means detects a connection or disconnection state of the video signal of the display section. 8. The display unit according to claim 5, wherein the display unit is a liquid crystal display in which the backlight is on or off.
The vehicle-mounted television receiver described.