JPS60127821A - Television receiver - Google Patents

Abstract

PURPOSE:To attain reception of an emergency alarm broadcast in a standby channel when a power of a television receiver is disconnected by providing an address representing a last channel position and an address representing standby channel position into a memory. CONSTITUTION:The address L storing a channel CH position during channel selection and an address W storing a standby CH position are provided to a memory 18, the address L is rewritten at each channel selection by a microcomputer muCM17 and the address W is written by preset. The muCM17 fetches the content of the address W when the power circuit 9 is disconnected and transfers the CH data to a channel selection circuit 3. If an emergency alarm is broadcast when the power supply 9 is disconnected, the emergency broadcast is received via the standby CH by using the power supply from a standby power supply 7. When the power supply 7 is restored after it has been once disconnected, the muCM17 is operative after a prescribed time by a power supply clear circuit 14, the address is fed to the circuit 3 and when an input terminal (g) is at a low level, the address L is fed to the circuit 3.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates in particular to a channel selection control device for a television receiver incorporating an emergency warning broadcast receiver.

The configuration of the conventional example and its problems The emergency warning broadcast signal superimposed on the audio signal of the television signal is received, the received signal is decoded by the emergency warning broadcast reception decoder connected to the audio detection stage, and the output is used to decode the received signal. A television receiver with a built-in emergency warning receiver has been developed that drives a control circuit that supplies power to the audio output stage to make emergency information audible even when night television is not being watched. .

An example of a conventional configuration of such a television receiver is as shown in FIG. Since it is necessary to constantly receive TV audio, the standby power supply 7 is used to connect the tuner 2, the tuning circuit 3 for enabling the tuner to receive reception on a predetermined channel, the control circuit A4 for controlling the tuning circuit, and the video intermediate frequency amplification/detection and audio intermediate frequency amplification/detection section 5;
supplies power to. The detected audio signal a is connected to an emergency warning broadcast reception decoder 6 and an audio amplification output stage 8. Since the emergency warning broadcast reception decoder 6 also needs to be in operation at all times, it is supplied with power by the standby power supply 7.

When the emergency warning broadcast is received, the control circuit B1○ is controlled by the control signal from the emergency warning broadcast reception decoder 6, and the power from the standby power supply 7 is supplied to the audio amplification output stage 8, and the emergency warning broadcast is transmitted. The sound is made audible through a speaker 11.

When a viewer turns on the power switch of the television, the control circuit A detects the operation, controls the power supply circuit 9, supplies power to the video processing and deflection processing circuits, and supplies power to the remaining circuits of the television receiver. everything will work. At this time, the control circuit A4 detects that the power supply circuit 9 has operated, and sends a control signal C to the control circuit B10, so that power to the audio output stage 8 is also supplied. The control circuit A of the television receiver with built-in emergency warning broadcast receiver having such a configuration is shown in more detail in FIG. A key matrix circuit 13 is connected to a group d of input ports of the microcomputer 150, in which keys for instructing valve channel positions, keys for turning on/off the power, etc. are arranged in a matrix. A group e of I10 ports of the microcomputer 16 are connected to the memory 16 and the channel selection circuit 3. The memory 16 is a non-volatile memory or a battery-backed memory. The tuning circuit 3 is composed of a D/A converter, a band launch circuit, and a low-pass filter, and is configured to apply a tuning control voltage and a UHF and VHF high band and low band switching voltage to the electronic tuning tuner. Power supply clear circuit 1
Reference numeral 4 applies a signal to prevent the microcomputer from operating until it resumes normal operation after a predetermined period of time after the power from the standby power supply 7 is applied to the microcomputer 15.

The output terminal f of the microcomputer 15 is connected to the memory 16, and writes to the memory 16.

It is designed to control reading. The memory 16 has an area for storing channel data and AFC offset data, and an address for storing the channel position during channel selection.

The input port q of the microcomputer 16 is the power supply circuit 9
When the power supply circuit 9 is turned on and the television is in the receiving state, a high level signal is applied, and when it is turned off, a low level signal is applied.

The microcomputer 15 has key sense, and when the power key is pressed, if q is high level, it will send a control signal to the output terminal of microcomputer 15 to disconnect the power supply port, and if q is low level, it will send a control signal to disconnect the power supply port. If so, it outputs a control signal to turn on the power circuit to h. microcomputer 15
When the power supply circuit is turned on, it reads the contents of the address in the memory 16, sends the channel data that was being selected just before the power was turned off to the tuning circuit, and selects the same channel ( (hereinafter referred to as the last channel).

In such a conventional television receiver with a built-in emergency warning broadcast receiver, it is necessary to select and disconnect a station providing an emergency warning broadcast transmission service before turning off the power switch.

If the user performs an emergency warning broadcast service,
- If you turn off the power with a station that is not currently selected, you will receive earthquake prediction information and other information. This results in not being able to receive emergency alerts while on standby.

Purpose of the Invention The present invention solves the above-mentioned problems of the prior art, and makes it possible to always receive the designated channel when the television receiver is turned off (standby state), and to receive the last channel when the television receiver is turned on. To provide a television receiver with a built-in emergency warning broadcast receiver that allows channel selection.

Structure of the Invention In the present invention, an address for storing a channel to be selected in a standby state is provided in advance in a non-volatile memory or a battery-backed memory, and a signal indicating the state of the power supply from the power supply circuit is used to When the power is turned off, standby channel data is sent to the channel selection circuit.

DESCRIPTION OF EMBODIMENTS FIG. 3 shows the configuration of a television receiver according to an embodiment of the present invention. The memory 18 is a nonvolatile memory, and has an area for storing channel data and AFC offset data, an address for storing the channel position during selection, and an address W for storing the standby channel position.

L is rewritten by the microcomputer every time a channel selection operation is performed, and W is written by the microcomputer when it is in a preset state.

Every time a specific channel is selected by the key matrix 13, the microcomputer 17 transfers the channel data in the memory 18 to the channel selection circuit 3. The channel selection circuit 3 has the same configuration as that explained in FIG.

When the power key of the key matrix 13 is pressed, the microcomputer senses the input terminal q, and if q is at a high level, outputs a control signal to cut off the power from the output terminal of the microcomputer 17, and the power supply circuit 9 cut. Thereafter, the microcontroller 17 takes in the contents of the address W of the memory 18 and transfers the channel data of the channel position pointed to by it to the channel selection circuit 3. Therefore, when the power is cut off and the television receiver with a built-in emergency warning broadcasting receiver is in standby mode, it will always tune to the specified channel, that is, the station that is providing the emergency warning broadcasting service. Therefore, whenever an emergency warning broadcast is transmitted, the broadcast is likely to be received by the emergency warning broadcast reception decoder.

When the standby power supply 7 is cut off due to a power outage, etc., the next time the standby power supply 7 is started, and the microcomputer 17 becomes operational again after a certain period of time by the power supply clear circuit 14, the microcomputer 17 is The contents of the address W of the memory 18 are read, the channel data of the standby channel position is transferred to the channel selection circuit 3, and the station providing the emergency warning broadcasting service is selected and placed in a reception standby state. After that, sense the input terminal q, and if q is low level, it will remain in the reception standby state, and if q is high level, it will read the address of memory 18 and transfer the last channel data to channel selection circuit 3. and selects the channel that the viewer was last tuning to.

The power supply circuit 9 has the same configuration as the conventional example, and uses a keep relay or the like to maintain the state controlled by the output from the microcomputer 17 until it is next controlled by h. The standby power supply 7 and the power supply clear circuit 14 have the same configuration as in the conventional example, and the input terminal group d1 of the microcomputer 17, the output terminal group e, and the output terminal f are also the same.

In this way, by having the address indicating the last channel position and the address W indicating the standby channel position in the memory 18, the standby channel is set when the power supply circuit 9 is off, and the standby channel is set when the power supply circuit 9 is turned on. Selected from the last channel.

Effects of the Invention As described above, according to the present invention, when the television receiver is disconnected by the viewer, the TV receiver is set to a pre-specified standby channel regardless of the station that was being selected at the time of disconnection. This is useful because it can be put on standby while emergency warning broadcasts can be received, and the listener does not have to tune in to a station that is providing the emergency warning broadcast service before turning off the power. be.

[Brief explanation of drawings]

FIG. 1 is a block diagram of a conventional television receiver with a built-in emergency warning broadcast receiver, FIG. 12 is a block diagram of its channel selection control circuit, and FIG. 3 is a television receiver according to an embodiment of the present invention. FIG. 2 is a block diagram of a channel selection control circuit of the machine. 2...Tuner, 3...Tuning selection circuit, 4
... Control circuit A, 6 ... Emergency warning broadcast reception decoder, 7 ... Standby power supply, 8 ...
Audio amplification output stage, 9... Power supply circuit, 10...
... Control circuit B, 11... Speaker, 13.
...Key matrix circuit, 15...Microcomputer, 16...Memo IJ, 17
・・・・・・Microcomputer.

Claims (1)

[Scope of Claims] An emergency warning broadcast receiving circuit that receives an audio detection signal as input, this circuit and a tuner section 2 channel selection circuit section. It has a standby power supply circuit that constantly supplies power to the video/audio intermediate frequency amplification and detection circuit regardless of whether the television receiver itself is turned on or off, and the channel selection circuit is controlled by a memory that stores channel selection information and a microcomputer. , an address in the memory for storing the channel that was being selected immediately before the viewer turned off the power, and an address for storing the channel to be selected when the power is turned off and operating only on standby power. A television receiver that can receive a specific channel in a standby state, and that when the power is turned on, the channel that was being received immediately before the power was turned off is received.