JPS6133084A - Television receiver - Google Patents

Abstract

PURPOSE:To omit a switching operation of a sound reproduction mode and to improve the operability with a TV receiver, by performing an automatic switching action in the same way as the sound reproduction set previously even in case the switch is needed for the sound reproduction mode for channel selection. CONSTITUTION:Switching parts 11L and 11R are controlled by the switch signal given from a microcomputer 13, and the sound reproduction mode of a sound reproduction circuit 8 is decided by the switching state of a mode switching circuit 11. The sound reproduction mode set previously is read out of a nonvolatile memory 21 with a channel that is designated newly as a selection channel through a channel switching operation. Then the reproduction mode of the circuit 8 is controled with switch so as to obtain the coincidence with the reproduction mode read out of the memory 21. With such a TV receiver, a sound reproduction mode exactly equal to that set in a channel selection mode is obtained automatically as long as a sound reproduction mode is previously set to a channel. Thus it is not needed to switch the sound reproduction mode when a channel is selected.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a novel television receiver, and in particular to a television receiver capable of receiving audio multiplex broadcasting. It is an object of the present invention to provide a novel television receiver with good operability, which is capable of switching to a preset audio playback mode for broadcast channels.

BACKGROUND OF THE INVENTION Audio multiplex broadcasting using television broadcasting has come to be performed in the United States as well. Audio multiplex broadcasting in the United States is L+R signal, L-R signal, and SAP.
(Separate Φ audio program) signal. The reproduction mode of the audio reproduction circuit built into the television receiver is MAIN mode, SA
It is possible to arbitrarily switch between three types of modes: P mode and BOTH mode. Incidentally, when the MAIN mode is set, the left channel signal is reproduced by the left speaker, and the right channel signal is reproduced by the right speaker. Furthermore, when selecting a channel on which audio multiplex broadcasting is not performed, the mode must be set to MAIN mode. Furthermore, when the SAP mode is set, the SAP signal is reproduced by the left and right speakers. When set to BOTH mode, R is set to one speaker.
The signal (monaural signal) is reproduced, and the SAP signal is reproduced by the other speaker.

By the way, if such a television receiver capable of receiving audio multiplex broadcasts for the United States is set to SAP mode, and after enjoying one channel's television broadcast, the user switches channels to enjoy another television broadcast. Noise often occurs when the newly selected channel is a channel that does not perform audio multiplex broadcasting. This is because, among broadcasting stations in the United States, there are stations that leave the carrier on when not broadcasting SAP, and stations that do not broadcast the carrier at all. Therefore,
Normally, the receiver side does not detect the absence of a carrier and apply muting. Therefore, the problem that noise is generated and causes discomfort to the viewers cannot be avoided. Furthermore, due to the audio multiplex broadcasting system, if you set the audio multiplex mode and select a channel that does not perform audio multiplex broadcasting, you will not be able to obtain the same sound as when you set the MAIN mode. Therefore, in such a case, after switching channels, it is necessary to switch the audio reproduction mode of the audio reproduction circuit to the MAIN mode.

On the other hand, when you enjoy broadcasting on a channel that does not have audio multiplex broadcasting, and then switch to a channel that does audio multiplex broadcasting, for example, when you try to change the audio playback mode to BOTH mode, Both the operation for switching the audio playback mode and the operation for switching the audio playback mode must be performed. Therefore, there was a problem of poor operability.

Problems to be Solved by the Invention However, the present invention attempts to solve the conventional problem that it is necessary to perform an operation to switch the audio playback mode when selecting a channel, resulting in poor operability. .

Means for Solving the Problems 1 - The means adopted by the present invention for solving the above problems is to store the audio reproduction mode set in advance for each channel in the audio reproduction mode storage means; hand,
j Tatsumi Every time you call a station, select part 1 from the audio playback mode storage means.
The audio reproduction mode set in advance for the station channel is read out, and the audio reproduction mode of the audio reproduction circuit is switched based on the read result.

According to the television receiver of the present invention, even if it becomes necessary to switch the audio playback mode when selecting a channel, the switching is automatically performed according to the preset audio playback mode. , there is no need to perform an operation to switch the audio playback mode, improving operability.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The television receiver of the present invention will be described in detail below with reference to embodiments shown in the accompanying drawings.

The drawings are for explaining an example of implementation of the television receiver of the present invention, and FIG. 1 is a block diagram showing the circuit configuration of the television receiver. In the figure, ■ is a tuner, 2 is a PLL circuit for controlling channel selection, 3 is a video intermediate frequency amplification circuit, 4 is a video detection circuit, 5 is a video reproduction circuit, and 6 is a cathode ray tube.

7 is an audio intermediate frequency amplification circuit; 8 is an audio reproduction circuit for reproducing the audio signal output from the audio intermediate frequency amplification circuit;
It consists of an audio multiplex signal demodulation circuit 9, a matrix 10, and a mode switching circuit 11 for switching audio reproduction modes. 1
2L is a left channel speaker, and 12R is a right channel speaker.

When the audio multiplexed signal 14-tone circuit 9 of the audio reproduction circuit 8 receives the audio multiplexed signal from the audio intermediate frequency amplification circuit 7, it separates and outputs the sum signal R1 difference signal L-R and the SAP signal. When an ordinary monaural signal, which is not an audio multiplexed signal, is received from the audio intermediate frequency amplification circuit 7, the monaural signal is output as is.

The matrix 10 is composed of the sum signal L+R and the difference signal L-.
To receive the R signal, separate the left signal R and the right signal R.
Output separately from two output terminals. Note that when receiving a normal monaural signal, the same monaural signal is output from the two terminals.

-The mode switching circuit 11 is connected to the left and right speakers 12L.
, 12R, a pair of switching units 11L, 1I
This pair of switching parts 11L and 11
R are always switched in the same manner as each other. Switching section lI corresponding to left speaker 2L
L has a first switching terminal connected to an output terminal that outputs the left signal of the matrix 10, a second switching terminal connected to an output terminal that outputs SAP of the audio multiplex signal demodulation circuit 9, and a third switching terminal. The terminal is the sum signal L of the audio multiplex signal demodulation circuit 9
It is connected to an output terminal that outputs +R, and a common terminal is connected to the speaker 2L.

In addition, the switching section 11 corresponding to the right speaker 2R
The first switching terminal of R is connected to the output terminal for outputting the right signal R of the matrix 10, and the second and third switching terminals are both connected to the output terminal for outputting the signal SAP of the audio multiplex signal demodulation circuit 9. , and the common terminal is speaker 2R
is connected to. This switching section 11L and II
The switching of R is controlled by a switching signal from a microcomputer 3, which will be described later, and the switching of the audio reproduction circuit 8 is controlled by the switching state of the switching section 11L and IIR, that is, the switching state of the mode switching circuit 11. An audio playback mode is determined.

The microcomputer 3 is used as a system controller for a television receiver, and 14 is its CPU, 15 is a ROM, 16 is a RAM, and 17 is an interface for receiving remote control signals. It is connected to a receiving circuit 18 for use. 19 is a photodiode for receiving a remote control signal using infrared light from a remote controller (not shown); and 20 is a photodiode for receiving a remote control signal using infrared light from a remote controller (not shown); It is sent to the station control PLL circuit 2.

Reference numeral 21 is a non-volatile memory that stores audio playback modes set in advance for each channel. Reference numeral 22 denotes an interface for sending out an audio playback mode switching signal, which serves to send out an audio playback mode switching signal to the mode switching circuit 11.

The non-volatile memory 21 is configured such that an audio reproduction mode for each channel can be written by appropriate presetting operations of a remote controller (not shown). Therefore, for each channel, the audio playback mode is preset as shown in the table below, for example. In addition, in the table, club "01" indicating the audio playback mode is MAI
N mode, rlo, + indicates SAP mode, r
tIJ indicates BOTH mode.

Incidentally, in this presetting, it is necessary to set channels on which audio multiplex broadcasting is not performed to the MAIN mode. For channels where audio multiplex broadcasting is performed, select the audio playback mode according to your preference.

FIG. 2 is a flowchart showing a program executed by the microcomputer 13 when a channel selection operation is performed.

(a) "Has a channel switching operation been performed?" When the main routine of the program is completed, it is determined whether a channel switching operation has been performed.

(b) "Reading the audio playback mode corresponding to the selected channel from the switching unit memory" above step (b)
If the result of the determination is rYes J, the preset audio playback mode for the channel newly designated as the selected channel by the channel switching operation is read from the nonvolatile memory 21. In this example, if the newly selected channel is the third channel, the read audio reproduction mode should be the BOTH mode (see the table above).

(c) ``Set the audio playback circuit to the audio playback mode read out from the non-volatile memory 21.'' When step (b) is completed, the audio playback circuit is set to the audio playback mode read out from the non-volatile memory 21 in step (b). 8. Therefore, if the selected channel is the third channel, regardless of the audio reproduction mode of the audio reproduction circuit before the channel switching operation, in this example, the BOTH mode is selected. It should be.

(d) "Tuning to the selected channel" When the above step (c) is completed, the channel selection control is performed so as to tune to the channel newly designated as the selected channel by the channel switching operation.

After that, return to step (a).

(e) "Has the audio playback mode been switched?" If the result of the determination in step (a) is rNoJ, that is,
If no channel switching operation has been performed, it is determined whether or not an operation for switching the audio reproduction mode has been performed.

This television receiver is designed so that the audio reproduction mode of the audio reproduction circuit 8 can be switched by appropriate operation of the remote controller during image reception, and this step (e) switches the audio reproduction mode. This is to determine whether or not an operation is being performed. by the way,
If the result of this determination is "NO", the process returns to step (a).

(f) [Switch the audio playback mode according to the switching operation] If the result of the judgment in Step 2 (e) is rYes J, the audio playback mode will be changed according to the newly specified audio playback mode by the audio playback mode switching operation. The audio reproduction mode of the audio reproduction circuit 8 is switched to .

(g) [Changing the audio playback mode settings for the currently selected channel according to the switching operationj When the above step (g) is completed, the preset audio playback mode settings for the currently selected channel will be changed. The audio reproduction mode is changed to the one specified by the audio reproduction mode switching operation.

Specifically, the audio reproduction mode for the currently selected channel in the nonvolatile memory 21 is rewritten in accordance with the switching operation. In other words, if the currently selected channel is, for example, the 4th channel.
channel, and the mode preset as the audio playback mode is MAIN mode, for example, when a switching operation is performed to switch to BOTH mode, the audio playback mode flag for the fourth channel in the nonvolatile memory 21 is set to "01" will be rewritten to "11".

After that, return to step (a). Incidentally, if the determination result in step (e) is "NO", the process immediately returns to step (a).

According to such a television receiver, if the audio reproduction mode is set for each channel in advance, the audio reproduction mode is automatically switched as set when a channel is selected. Therefore, there is no need to switch the audio playback mode when selecting a channel. Unless an inappropriate audio playback mode is set, noise may occur when switching from a channel receiving a channel with the audio playback mode set to SAP mode, for example, to another channel that does not have audio multiplex broadcasting. The inconvenience of being in a state where this occurs can be avoided.

Further, while selecting a channel in such a television receiver, the audio reproduction mode for that channel can be switched by an audio reproduction mode switching operation. Therefore, for example, if you initially enjoy audio in the MAIN mode, but later want to enjoy it in the SAP mode, all you have to do is switch the audio playback mode to the SAP mode. When the audio reproduction mode is switched in this way, the preset contents for the selected channel stored in the nonvolatile memory 21 are also automatically switched.

Effects of the Invention As described above, the television receiver of the present invention allows the audio reproduction mode storage means to store the audio reproduction mode set in advance for each channel, and each time a channel is selected, the audio reproduction mode is changed. The audio reproduction mode set in advance for the selected channel is read out from the storage means, and the audio reproduction mode of the audio reproduction circuit is switched based on the read result.

Therefore, according to the television receiver of the present invention, even if it becomes necessary to switch the audio playback mode when selecting a channel, the switching is automatically performed according to the preset audio playback mode. This eliminates the need for additional operations, improving operability.

[Brief explanation of drawings]

The drawings are for explaining an example of implementation of the television receiver of the present invention. Figure 1 is a block diagram showing the circuit configuration of the television receiver, and Figure 2 is a block diagram showing the circuit configuration of the television receiver. 3 is a flowchart showing a program executed when Explanation of symbols 8...Audio playback circuit, 21...Audio playback mode storage means (non-volatile memory)]

Claims (1)

[Claims] (1) A television receiver that has a function to demodulate audio multiplex broadcasting and has an audio playback circuit that receives an audio playback mode switching signal and switches to an audio playback mode according to the switching signal, and is configured in advance for each channel. The device has an audio reproduction mode storage means for storing the audio reproduction mode set in advance, and reads out the audio reproduction mode preset for the selected channel from the audio reproduction mode storage means each time a channel is selected, and sets the audio reproduction mode to the read audio reproduction mode. A television receiver characterized in that the audio reproduction mode of the audio reproduction circuit is switched and controlled.