JPH0129447B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to an emergency warning broadcast receiver in a television receiver.

Configuration of a conventional example and its problems The configuration of an emergency warning broadcast receiving section in a conventional television receiver is shown in FIG.

Power is always supplied to the tuner section, intermediate frequency amplification/detection section, and audio intermediate frequency amplification/detection section of the television receiver from a separate power supply regardless of whether the television receiver's power switch is turned on or off, and when on standby to receive emergency broadcasts. It is becoming a state. A voice detection output is supplied to point A. This audio detection output is connected to the emergency warning broadcast decoder circuit 1,
Demodulation and code discrimination of the FSK signal are performed. Output B from the emergency warning broadcast decoder circuit 1 is connected to an audio output stage power supply control circuit 2. Point D is connected to a power source generated by a flyback transformer, and a voltage is applied when the television receiver is turned on. Audio output stage power supply control circuit 2 is B
and D, and when the power of the television receiver is turned on or an emergency warning broadcast is received, output C is generated, switch 6 is turned on, and power supply H is applied to audio output amplification circuit 5. Apply. The audio detection output A is also connected to the volume control circuit 3.

The volume control circuit 3 performs volume control using the DC voltage F from the volume control switching circuit 4. The output E from the volume control circuit 3 is input to the audio output amplification circuit 5. The volume control switching circuit 4 is output B from the emergency warning broadcast decoder circuit 1, and is a D/A switch controlled by a remote control etc. of the television receiver.
The output voltage G from the converter and the midpoint voltage of emergency alarm volume volume 7 are switched, and regardless of the state of output voltage G, when an emergency warning broadcast is received, the volume is set at emergency alarm volume volume 7. This is a circuit to accomplish this. I is the power supply added to the emergency warning volume volume 7. The output of the audio output circuit 5 is connected to a speaker 8.

FIG. 2 shows in detail the volume control switching circuit 4 of the emergency warning broadcast receiving section in the television receiver having such a configuration. B is the output from the emergency warning broadcast decoder circuit 1 as described above. This B is connected to the control terminal of the analog switch 11 and the input of the inverter 9. The output of inverter 9 is connected to a control terminal of analog switch 10. The input end of the analog switch 10 is connected to G, and the output end is connected to the input end F of the volume control circuit 3. The input end of the analog switch 11 is connected to the midpoint of the emergency warning volume volume 7, and the output end is connected to the aforementioned F. When an emergency warning broadcast is received and B becomes high level, analog switch 1
1 becomes conductive, the analog switch 10 becomes non-conductive, and the input F to the volume control circuit 3 becomes the voltage set by the emergency warning volume volume 7. If the emergency warning volume 7 is placed on the front of the television receiver so that the user can adjust it, it will be possible for the user to accidentally set the volume 7 to the minimum setting and no sound will be output even if an emergency broadcast is received. It happens.

Furthermore, if the emergency alert volume volume 7 is provided inside the receiver, the user will not be able to adjust the volume depending on the content of the emergency alert broadcast, or will not be able to adjust the volume when testing the emergency alert broadcast receiver. It's inconvenient.

Purpose of the Invention The present invention eliminates the above-mentioned drawbacks, and makes it possible to keep the volume constant until the user confirms that the emergency broadcast has been received, and then adjust the volume with the emergency alert volume after confirmation. .

Structure of the Invention The present invention enables the control voltage of the volume control circuit using the DC voltage of the television receiver to be switched by three switch circuits, and controls the switch circuit between the output from the emergency warning broadcast reception decoder circuit and the output from the emergency warning broadcast receiving decoder circuit. The control voltage is controlled by the output of the memory circuit controlled by the alarm reception confirmation switch, and the control voltage is the conventional volume control voltage of the television receiver, the voltage from the emergency alarm volume volume, and the fixed resistor. When an emergency alert is received, the volume is always constant, and after confirmation of reception, the volume is adjusted by the emergency alert volume. Except for reception, the volume is set to the conventional volume level of a television set.

DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below with reference to FIG.

Output B of the emergency warning broadcast decoder circuit is connected to an inverter 12 and one input end of a two-input AND circuit 15. The other input is connected to the other end J of the emergency warning broadcast confirmation switch 18.
A chattering prevention circuit consisting of a resistor 16 and a capacitor 17 is also connected to.

The output of the inverter 12 is the input of the inverter 13, and the output of the inverter 12 is also connected to the control terminal A of the analog switch 23. The output of the inverter 13 is also connected to a clock input terminal of a D flip-flop 14 and one input terminal of a two-input AND circuit 22. The D input and preset terminal PR are connected to power supply I. The output terminal of the two-input AND circuit 15 is connected to a clear terminal OKR. The output terminal Q of the D flip-flop 14 is connected to the control terminal U of the analog switch 25. The output terminal Q is connected to the other input terminal of the two-input AND circuit 22, and the output terminal of 22 is connected to the control terminal A of the analog switch 24.
The output terminals of the analog switches 23, 24, and 25 are wired together and connected to the input terminal F to the volume control circuit, and the output terminals of the analog switches 23, 24, and 25 are connected to the input terminal F of the volume control circuit. The midpoint voltage of the emergency broadcast volume volume 19, which is the input of 24, and the power supply voltage I, which is the input of the analog switch 25, are connected to the resistors 20 and
It is configured to switch the voltage divided by 1.

Next, the operation of this circuit will be explained with reference to FIG. Until t ₁ , no emergency broadcast is received, and the output B of the emergency warning broadcast reception decoder circuit is low. Therefore, the CLR terminal is low, the output is high, and Q is low. Therefore, A is at a high level, A and C are at a low level, the analog switch 23 is conductive, and the others are non-conductive. When an emergency warning broadcast is received at time t ₁ ,
B becomes high level, and the CLR terminal also becomes high level. Since the CK terminal becomes high level with a delay of the passage time of the inverters 12 and 13, Q is inverted at the time of rising. Therefore, C becomes high level, A and A become low level, only analog switch 25 becomes conductive, and resistors 20 and 21
The voltage divided by is connected to the volume control input terminal, and the sound near the maximum volume will be output. When the user confirms the broadcast content and presses the switch 18 at time _t2 , the CLR terminal becomes low level while the switch is pressed, and Q is inverted. This state is switch 18
It is retained even if you stop pressing . Therefore, A is at a high level, A and C are at a low level, only the analog switch 24 becomes conductive, and the volume is controlled by the emergency broadcast volume volume 19. When the emergency warning broadcast ends at time _t3 , A becomes high level and the conventional volume control voltage of a television receiver is supplied to F.

Effects of the Invention As described above, according to the present invention, when an emergency warning broadcast is received, the sound close to the maximum volume is forcibly output, and after the user confirms it, the emergency broadcast volume volume is adjusted. It is convenient for the user to be able to receive the emergency broadcast at high volume and know the emergency situation even if the user accidentally lowers the volume of the emergency broadcast volume to the minimum and no sound is output. . Moreover, since it is independent from the conventional volume control of a television receiver, it is useful because the conventional volume control of a television receiver cannot be changed when the power is not turned on.

[Brief explanation of drawings]

Fig. 1 is a block diagram explaining the configuration of a conventional emergency warning broadcast receiving section for a television receiver, Fig. 2 is a wiring diagram of the volume control switching circuit section of the conventional emergency warning broadcast receiving section, and Fig. 3 4 is a wiring diagram of a volume control switching circuit of an emergency warning broadcast receiver according to an embodiment of the present invention, and FIG. 4 is a timing diagram illustrating the circuit operation of the present invention. 12, 13... Inverter, 14... D flip-flop, 15, 22... AND circuit, 23, 24,
25...Analog switch, 18...Emergency warning broadcast reception confirmation button, 19...Emergency broadcast volume volume.

Claims (1)

[Claims] 1. A power supply means for supplying power to the tuner section, the intermediate frequency amplification/detection section, and the audio intermediate frequency amplification/detection section regardless of whether the power switch of the television receiver is turned on or off, and the audio intermediate frequency amplification/detection section. an emergency warning broadcast decoder circuit and an audio control circuit respectively connected to the output side; an audio output amplification circuit connected to the output side of the volume control circuit;
an audio output stage power supply control circuit that is operated by the output of the emergency warning broadcast decoder circuit when an emergency warning broadcast is input and controls the power supply voltage to be supplied to the audio output amplifier circuit; and a television receiver. An original conventional volume control voltage input terminal, a volume volume exclusively for emergency warning broadcasting, constant volume setting means for setting emergency warning broadcasting to the maximum volume or close to it, and a switch for confirming emergency warning broadcasting. Volume control voltage applied to the above input terminal,
and a volume control switching circuit that selects either one of a volume control voltage based on a volume volume and a volume control voltage based on a constant volume setting means and supplies the selected volume to the volume control circuit, the volume control switching circuit having one end in common. a first one connected to the volume control circuit, and having the other end connected to the input terminal, a volume volume exclusively for emergency warning broadcasting, and a constant volume setting means;
It is equipped with second and third switch circuits, and when an emergency warning broadcast is not being received and the emergency warning broadcast confirmation switch is not turned on, the first switch circuit is conductive and the second and third switch circuits are turned on. The circuit is cut off, and when the above-mentioned emergency warning broadcast confirmation switch is off and an emergency warning broadcast is received, the third switch circuit becomes conductive and the first and second switch circuits are cut off, and the emergency warning broadcast is received. An emergency warning broadcast receiving device configured such that when an emergency warning broadcast confirmation switch is turned on in the state, a second switch circuit is made conductive and the first and third switch circuits are cut off.