JPH08186776A - Voice controller - Google Patents

Abstract

PURPOSE: To limit the sound volume in a commercial mode and to obtain a TV receiver that always has the optimum sound volume by outputting the signals through a logic circuit only when a reception mode signal is switched to a stereo broadcast from a monaural mode. CONSTITUTION: A logic circuit 18 outputs a control signal 19 to reduce the sound volume when the transmission mode of a multivoice signal is switched to a stereo broadcast from a monaural broadcast and as long as the multivoice signal of the transmission mode and a selection signal 14 of the demodulation circuit of a picture receiver are set in modes except a forced monaural mode. When the signal 19 is inputted to a sound volume control circuit 20, the voice signals which suppress the amplification degrees of low frequency amplifier circuits 2 and 3 of left and right voices and also reduce their sound volumes are outputted from the sound volume control output 22 as long as a control switch 21 is kept in an ON state. When the transmission mode of the multivoice signal is switched again to the monaural broadcast from the stereo broadcast, the circuit 18 outputs the signal 19 to increase the sound volume. When the signal 19 is inputted to the circuit 20, the signals are outputted to increase the amplification degrees of both circuits 2 and 3.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a volume control section in an audio circuit of a television receiver or the like.

[0002]

2. Description of the Related Art A block diagram of a conventional audio circuit of a television receiver is shown in FIG.

In FIG. 3, 1 is an audio multiplex signal demodulation circuit, 2 and 3 are left and right audio low frequency amplification circuits, 4 and 5 are power amplification circuits, 6 and 7 are speakers, and 8 and 9 are audio multiplex signal demodulation circuits. Left and right audio signals demodulated by 1; 10 and 11 are audio signals whose volume and balance are adjusted; 12 and 13 are audio output signals; 14 is a demodulation circuit selection signal;
Reference numeral 7 is a volume adjustment signal.

In such a conventional circuit block configuration, the voice detection signal 16 in which the sub voice signal and the control signal are multiplexed is demodulated by the voice multiplexed signal demodulation circuit 1 into a stereo signal or a bilingual signal. At this time, the selection signal 14 of the demodulation circuit performs main / sub audio switching and monaural / stereo selection switching, and the audio content linked with the demodulation selection is externally output as the multi-mode signal 15 for the broadcast signal and displayed. Used for etc.

The signal subjected to RL separation by the audio multiplex signal demodulation circuit 1 is amplified by the low frequency amplification circuits 4 and 5 and supplied to the speakers 6 and 7. The audio multiplexed signal demodulation circuit 1 identifies and demodulates monaural broadcasting and polyphonic broadcasting according to the content of the broadcast signal. At this time, the multi-tone broadcast has two types, stereo and bilingual, and is discriminated by the pilot signal.

[0006]

In the audio circuit of the above-mentioned conventional television receiver, when the volume is increased by switching to the commercial mode by broadcasting, the volume is output as it is, which is annoying. was there. Therefore, an object of the present invention is to provide an audio control device capable of reducing the sound volume only during the commercial, focusing on the change of the audio mode of the broadcast signal during the commercial.

[0007]

In order to achieve the above object, the present invention provides a voice multiplex signal demodulation circuit for determining a reception mode in a voice multiplex signal receiving device, and an output from the voice multiple signal demodulation circuit. A logical circuit that logically operates the reception mode signal, a volume control circuit that outputs a signal that limits the volume by the output of the logic circuit, and a low-frequency amplification circuit whose amplification degree is controlled by the volume control circuit. The logic circuit is configured to output a signal only when the reception mode signal changes from monaural to stereo.

[0008]

According to the present invention, when the monophonic broadcast is being received, the broadcast mode is changed and the volume is lowered when the commercial (stereo mode) is set, and the broadcast mode is changed again and the commercial (stereo mode) is ended. ,
When it comes to monaural broadcasting, the volume is increased (restored).

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, a structure according to an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram of a volume control device of the present invention.

In FIG. 1, reference numeral 1 is a voice multiplexed signal demodulation circuit, 18 is a logic circuit for detecting a sub voice mode and changing a volume control voltage output, 20 is a volume control circuit corresponding to the logic circuit 18, and 21 is optional. The control switch signal for controlling and canceling the volume, 22 is the volume control output, and 17 is the volume adjustment signal, and those with the same numbers as in FIG. 3 have the same configuration.

FIG. 2 is a timing chart for explaining the operation of the logic circuit 18 and the volume control circuit 20.

The logic circuit 18 operates in the multi-sound signal transmission mode when the signals of the multi-sound signal transmission mode (monaural, stereo, two-voice) and the selection signal 14 of the demodulation circuit on the receiver side are other than forced monaural. , When switching from monaural broadcasting to stereo broadcasting (in FIG. 2, selection signal 1
4 is switched from H to L), the control signal 19 for lowering the volume is output from the logic circuit 18. (The control signal 19 for lowering the volume switches from L to H.)

When the control signal 19 for lowering the volume is input to the volume control circuit 20, the volume control output 22 outputs the signal when the control switch 21 is on (for example, the commercial voice restriction mode switch is operated). 2 and 3
The left and right audio low-frequency amplification circuits are suppressed in amplification degree, and the audio signal whose volume is lowered is output.

When the transmission mode of the sound multi-signal is switched from the stereo broadcast to the monaural broadcast again, the logic circuit 18 outputs the control signal 19 for increasing (returning) the volume.

When this output is input to the volume control circuit 20, when the control switch 21 is on, the volume control output 2
A signal for increasing the amplification degree of the low-frequency amplifier circuits 2 and 3 is output to 2 in order to increase the volume. That is, if the monaural broadcast is being received as a basic condition, the volume will be lowered only when the monaural broadcast is switched to the stereo broadcast.

Further, as can be seen from FIG. 2, when the control switch 21 is turned off, the above operation does not operate.

As described above, according to the volume control apparatus of the embodiment of the present invention, the volume control output is controlled by using the logic circuit for identifying the broadcast mode, the volume control circuit controlled by the logic output, and the control switch. By controlling and limiting the volume when the broadcast sound multimode is switched from the monaural broadcast to the stereo broadcast, the volume of commercials and the like can be automatically lowered.

[0019]

As described above, according to the present invention, in the audio multiplex signal receiving apparatus, the audio multiplex signal demodulating circuit for determining the receiving mode and the receiving mode signal output from the audio multiplex signal demodulating circuit are logically operated. And a volume control circuit that outputs a signal for limiting the volume by the output of the logic circuit, and a low-frequency amplification circuit whose amplification degree is controlled by the volume control circuit. Since the configuration is such that the signal is output only when the mode signal changes from monaural to stereo, there is an excellent effect that the volume during commercials can be limited and a television receiver with an optimal volume can be provided at all times.

[Brief description of drawings]

FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention.

FIG. 2 is a timing chart showing the operation of the embodiment of the present invention.

FIG. 3 is a block diagram showing a conventional configuration.

[Explanation of symbols]

 1 audio multiple signal demodulation circuit 2, 3 low frequency amplification circuit 4, 5 power amplification circuit 6, 7 speaker 18 logic circuit 21 volume control circuit

Claims (2)

[Claims] 1. A voice multiple signal receiving apparatus, a voice multiple signal demodulating circuit for determining a receiving mode, a logic circuit for logically operating a receive mode signal output from the voice multiple signal demodulating circuit, and an output of the logic circuit. A sound volume control circuit for outputting a signal for limiting the sound volume, and a low-frequency amplification circuit whose amplification degree is controlled by the sound volume control circuit.
The audio control device, wherein the logic circuit outputs a signal only when the reception mode signal changes from monaural to stereo. (2)