JPS6364414A - Broadcast receiving set - Google Patents

Abstract

PURPOSE:To eliminate necessity of operation of a viewer aud eliminate waste of electric power and annoyance to neighbors by detecting interruption of broadcast waves during receiving in the state of power source on, and cutting off the power source automatically. CONSTITUTION:Video amplification signals after detection inputted from a video amplifier circuit 5 are converted to voltage by a frequency/voltage converter 25 and this output voltage is compared with a reference voltage 1 V0 of relatively small value. When the output voltage becomes lower than the reference voltage V0, a driving signal is outputted from a comparator 26 to operate a power source driving circuit 27, and a power source switch S is made to cut off state. That is, when broadcast in receiving is terminated, and broadcast waves of that frequency is not received by an antenna, output frequency of the circuit 5 becomes substantially'', and output voltage of the converter 25 also becoms '0' and the power source switch becomes off. Accordingly, no annoyance is given to neighbors in next morning even if it is forgotten to switch off at night.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to broadcast receivers such as television receivers and radio receivers, and particularly relates to an automatic power-off technique for such broadcast receivers.

[Conventional technology]

Conventional broadcast receivers include those that are equipped with only a main power switch as a power control means, and those that are equipped with a sub power switch that is provided in a subsequent stage in addition to the main power switch. 0 with a remote control mechanism that uses sonic signals or infrared signals.
There is one that is configured to allow N10FF control. Therefore, the power ON10 F F operation of the broadcast receiver is basically performed by manual operation of the main power switch (button), or in the case of a receiver having a remote control mechanism as described above, the power ON10 F F operation is performed by the main power switch.
In addition to the 0FF operation, the sub power switch was remotely controlled using the remote control mechanism.

[Problem that the invention seeks to solve]

However, in the case of the conventionally configured broadcast receiver described above, in order to turn on/off the power, it is necessary to manually operate the main power switch (button).
Alternatively, even if it is performed by remote operation using a remote control mechanism, in any case, it is necessary to perform the operation based on the viewer's active will.

This poses almost no problem when it comes to turning on the power, but there is still a lot of room for improvement when it comes to turning off the power, due to the following circumstances.

In other words, recently, with the increase in late-night broadcasts, people often watch TV and radio until late at night, but they often accidentally fall asleep while watching, and as a result, the broadcast receiver has to be turned off. The broadcast receiver will be left in the ON state without being operated, and therefore, even if the broadcast being received ends and radio waves of that frequency are no longer transmitted (in other words, even if the broadcast radio waves are no longer received), the broadcast receiver will remain in the ON state. In the case of television receivers in particular, only a mottled pattern is displayed on the screen and loud noise is output from the speakers, which continues until the next morning when the broadcast begins. become.

This not only wastes a lot of power, but can also cause noise problems that are extremely nuisance to neighbors.

The present invention has been made in view of the above-mentioned conventional circumstances, and the purpose of the present invention is to automatically turn off the power when the broadcast being received ends, even if the viewer accidentally falls asleep late at night and forgets to turn off the power. It is an object of the present invention to provide a convenient broadcasting receiver whose power can be cut off at any time.

[Means for solving problems]

In order to achieve the above object, the broadcast receiver according to the present invention is configured to be able to detect the interruption of the broadcast radio waves being received while the power is on, and to automatically detect the interruption of the broadcast radio waves when the interruption of the broadcast radio waves is detected. The device is equipped with an automatic power cut-off mechanism configured to cut off the power automatically.

[Effect]

The effects achieved due to the above characteristic configuration are as follows.

That is, according to the broadcast receiver according to the present invention, as will become clearer from the description of specific embodiments described later, when the power is turned on, the broadcast being received ends and the broadcast radio waves of that frequency are broadcast. When the receiver stops receiving signals, the automatic power shutoff mechanism configured as described above operates and automatically shuts off the power without requiring any operation from the viewer, so even if the viewer unexpectedly falls asleep late at night, etc. Even if you forget to turn off the power to your broadcast receiver, the power will be automatically cut off when the broadcast you are currently receiving ends. This will definitely eliminate the inconvenient and wasteful situations that tend to occur in the past, such as leaving things unattended, as well as the associated problems of large amounts of electricity wasted and the generation of noise that is a huge nuisance to the neighborhood. I can do it now.

〔Example〕

Hereinafter, specific embodiments of the present invention will be described based on the drawings.

FIG. 1 is a block circuit diagram schematically showing the overall configuration of a television receiver as a broadcast receiver configured to apply the present invention. Note that the present invention is basically applicable to both color television receivers and monochrome television receivers, so the first aspect of the present invention is applicable to both color and monochrome television receivers.
For convenience, the figure shows the overall schematic configurations of a monochrome television receiver and a color television receiver at the same time. That is, in FIG. 1, the part indicated by dotted lines is a circuit part specific to color television receivers, and the part indicated by double solid lines is an automatic power cutoff mechanism X, which is a circuit part unique to the present invention. The other portions indicated by solid lines are circuit portions that are substantially common to both monochrome television receivers and color television receivers.

Now, the configuration of the circuit portion except for the automatic power cut-off mechanism X that is unique to the present invention is already well known as a general monochrome television receiver and a color television receiver, so it will be described very briefly here. I'll just explain it.

That is, 1 is an antenna that receives television waves transmitted from a broadcasting station and converts them into high-frequency current. 2 is a tuner, which includes a tuning circuit 2A that selects a high-frequency current of a desired broadcasting frequency from among high-frequency currents of various frequencies flowing from the antenna 1, and a tuning circuit 2A that selects a high-frequency current of a frequency related to a desired broadcast from among high-frequency currents of various frequencies flowing from the antenna 1; A high frequency amplification circuit 2B that amplifies the high frequency current at the same frequency, and a local oscillation circuit 2C that generates a current with a frequency corresponding to the selected frequency.
and a mixing circuit 2D that mixes both output currents from the high frequency amplifier circuit 2B and the local oscillation circuit 2C to generate an intermediate frequency current.

Below, the video output system will be mainly explained.

Reference numeral 3 denotes an intermediate frequency amplification circuit that amplifies the intermediate frequency current (including the video signal and the audio signal) output from the mixing circuit 2D of the tuner 2. 4 is a video signal (including a video current and a synchronization signal in the case of a monochrome television, and a brightness signal in the case of a color television) by AM detection from the signal output from the intermediate frequency amplification circuit 3.

This is a video detection circuit that extracts the carrier color signal and synchronization signal). In this video detection circuit 4, in the case of a monochrome television receiver, the audio signal is super-hetero gain detected to obtain the second audio intermediate frequency, but in the case of a color television, the subsequent color video The audio signal is cut by a trap circuit so as not to adversely affect the signal. Reference numeral 5 denotes a video amplification circuit that amplifies the video signal output from the video detection circuit 4.

In the case of a monochrome television receiver, the video signal output from the video amplification circuit 5 (from which the audio signal has been removed by the trap circuit in its output stage) is sent to the cathode or grid of the monochrome picture tube 6. By applying this voltage, the electron beam emitted from the electron gun of the monochrome picture tube 6 is controlled, and the intensity of the electron beam is changed according to the magnitude of the video signal. Further, the video signal output from the video amplification circuit 5 is also input to the synchronization signal separation circuit 7, where only the synchronization signal is extracted from the video signal, and furthermore, the synchronization signal is vertically After being separated into a vertical synchronizing signal and a horizontal synchronizing signal by a synchronizing signal extraction circuit 8 and a horizontal synchronizing signal extraction path 9, the signals are further converted into sawtooth currents by a vertical oscillation circuit 10 and a horizontal oscillation circuit 11, respectively.
The vertical sawtooth current and the horizontal sawtooth current are applied to the monochrome picture tube 6. Further, the horizontal sawtooth current output from the horizontal oscillation circuit 11 is also supplied to the flyback transformer of the high voltage power supply circuit 2 to generate a high voltage, and the high voltage is applied to the monochrome picture tube 6.
It is supplied to the electron gun.

On the other hand, in the case of a color television receiver, the video amplification circuit 5 mainly amplifies the brightness signal without amplifying the carrier color signal much, and the brightness signal and the color signal are simultaneously received in a color image, which will be described later. to join the pipe,
It is configured to delay the output of the brightness signal for a predetermined period of time. The signal output from the video amplification circuit 5 is directly input to the matrix circuit 1 as a brightness signal, and is also input to the band amplification circuit 13, where the carrier color signal and the color synchronization signal are input. Only the frequency portion containing the color signal is greatly amplified to extract the carrier color signal and the color synchronization signal. And the band amplification circuit 1
The carrier color signal and color synchronization signal outputted from the blue demodulation circuit 14. It is input to the red demodulation circuit 15 and the color subcarrier generation circuit 16, and the color subcarrier generation circuit I
The output signal from 6 is input to a phase delay circuit 17.

That is, the color subcarrier generation circuit 16 and the phase delay circuit 17 generate color subcarriers whose phases are different from each other by 90 degrees from the color synchronization signal, and the color subcarrier from the color subcarrier generation circuit 16 is sent to the red demodulation circuit 15. , and color subcarriers whose phases differ by 90 degrees from the phase delay circuit 17 are input to the blue demodulation circuit 14. As a result, the carrier color signal is detected in each of the blue demodulation circuit 14 and red demodulation circuit 15, and the blue signal (B) and the red signal (
The blue signal (B) and the red signal (R) are input to the matrix circuit 18. The matrix circuit 18 receives the input brightness signal and blue signal (B).

Based on the red signal (R), a red signal (R) of a predetermined strength
, a blue signal (B), and a green signal (G), and supply these color signals to the red electron gun, blue electron gun, and green electron gun of the color picture tube 19, respectively. Note that the color picture tube 19 also receives a vertical saw current from the vertical oscillation circuit 10, a horizontal saw current from the horizontal oscillation circuit 11, and a high voltage power supply circuit 12, as in the case of the monochrome television receiver. High voltage electricity is applied from

Next, the audio output system will be explained.

In the case of a monochrome television receiver, the second audio intermediate frequency generated in the video detection circuit 4 is input to the audio intermediate frequency amplification circuit 20 and amplified, as in a normal FM radio, and then the audio The signal is FM-detected by the detection circuit 21, further low-frequency amplified by the low-frequency amplification circuit 22, and then supplied to the speaker 23.

On the other hand, in the case of a color television receiver, since the video detection circuit 4 cuts the audio signal as described above, the output signal from the intermediate frequency amplification circuit 3 is guided to the second audio detection circuit 24. generates a second audio intermediate frequency, and transmits the second audio intermediate frequency to the audio intermediate frequency amplification circuit 2;
0. From then on, the process is the same as in the case of the monochrome television receiver.

Now, in the monochrome television receiver or the color television receiver configured as described above, the automatic power cut-off mechanism X, which is a circuit part unique to the present invention, in this embodiment It is connected to the output stage of the circuit 5, and is configured to be able to detect the interruption of the broadcast radio waves being received while the power is on, and automatically detect the interruption of the broadcast radio waves when the interruption of the broadcast radio waves is detected. Configured to shut off power.

That is, as shown in FIG. 2, the automatic power cutoff mechanism X includes an F/V converter 25 that converts the detected video amplified signal inputted from the video amplification circuit 5 into F/V (frequency/voltage); Compare the output voltage ■ from the F/V converter 25 with the reference voltage V (a relatively small value), and
The output voltage V from the /V converter is the reference voltage ■. a comparator 26 that outputs a drive signal when the
The power source drive circuit 27 receives the drive signal from the comparator 26 and automatically turns off the power switch S of the broadcast receiver.

Therefore, when the broadcast that is being received ends while the broadcast receiver is in the power ON state, and the broadcast radio waves of that frequency are no longer received from the antenna 1, the output frequency from the video amplification circuit 5 becomes substantially 0, and accordingly. F/V converter 25
Since the output voltage V from is also substantially O (<VO),
The comparator 26 outputs a drive signal to the power supply drive circuit 27, whereby the power switch S of the broadcast receiver is automatically turned off without the need for any operation by the viewer.

FIG. 3 shows another embodiment of the automatic power-off mechanism and a reset circuit 29 for returning the integrating circuit 28 to its initial state at regular intervals.

The rest of the configuration is the same as that of the above embodiment, and its operation is also obvious from the description of the above embodiment, so its explanation will be omitted.

Incidentally, in each of the embodiments described above, the power switch S that is automatically cut off by the automatic power cutoff mechanism It may also be a sub-power switch. However, if the automatic power cutoff mechanism X is configured to automatically shut off the latter sub power switch, the power supply drive circuit 27 in the automatic power cutoff mechanism Alternatively, an interlocking configuration may be adopted in which the sub power switch is forcibly returned to the ON state in conjunction with the cutoff operation of the main power switch. Furthermore, in a broadcast receiver equipped with a remote control mechanism, the sub power switch for remote control may be used as is as the sub power switch.

In the above-mentioned embodiment, the automatic power cut-off mechanism Not limited to the output stage of the video detection circuit 4
The audio detection circuit 2 in the audio output system, which is limited to the video output system, may be used as long as it is a line downstream from the
It may be a line subsequent to I. Furthermore, it goes without saying that the present invention is applicable not only to the above-mentioned television receiver but also to other broadcast receivers such as radio receivers and teletext receivers. It can be easily inferred from the explanation.

〔Effect of the invention〕

As is clear from the detailed description above, the broadcast receiver according to the present invention is configured to be able to detect the interruption of the broadcast radio waves being received while the power is on, and to detect the interruption of the broadcast radio waves. The system is equipped with an automatic power cut-off mechanism that automatically cuts off the power when the signal is detected, so when the broadcast being received ends and the broadcast receiver no longer receives the broadcast radio waves of that frequency. , the automatic power cut-off mechanism configured as described above operates and automatically cuts off the power, so even if the viewer forgets to turn off the broadcast receiver due to unexpected sleep in the middle of the night, the broadcast receiver will not be interrupted during reception. When the broadcast ends, the power is automatically cut off, which is an inconvenience that tends to occur in the past, such as accidentally forgetting to turn off the power and leaving the broadcast receiver unattended until the next morning. Moreover, the excellent effect of being able to reliably solve the conventional problems of the occurrence of unnecessary situations, the accompanying large waste of electricity, and the generation of noise that is a great nuisance to the neighborhood has been achieved.

[Brief explanation of the drawing]

The drawings show specific embodiments of the present invention; FIG. 1 is an overall schematic block circuit diagram of a television receiver as an example of a broadcast receiver, and FIG. 2 is a detailed block circuit diagram of the main parts. , and FIG. 3 is a detailed block circuit diagram of main parts according to another embodiment. 5... Video detection circuit, 21... Audio detection circuit, 25
...F/V converter, 26...Comparator, 2
7...Power supply drive circuit, 28...Integrator circuit, 29...
・Reset circuit, ■...Output voltage, V. ...Reference voltage, S...Power switch, X...Automatic power cutoff mechanism.

Claims (7)

[Claims] (1) An automatic power supply that is configured to be able to detect that the broadcast radio waves being received are interrupted while the power is on, and that is configured to automatically shut off the power when the interruption of the broadcast radio waves is detected. A broadcast receiver characterized by being provided with a cutoff mechanism. (2) The automatic power cutoff mechanism is connected to an F/V converter connected to a line downstream of a detection circuit for extracting video signals or audio signals from received radio waves, and the output voltage and reference from the F/V converter. and a power supply drive circuit that automatically turns off a power switch when the comparator detects that the output voltage from the F/V converter has become equal to or less than the reference voltage. Claim No. 1 (1)
Broadcasting receiver described in section ). (3) The automatic power cutoff mechanism includes an integrating circuit connected to a line downstream of the detection circuit for extracting video signals or audio signals from received radio waves, and returning the integrating circuit to its initial state at regular intervals. a reset circuit; a comparator that compares the output voltage from the integration circuit with a reference voltage; and a power switch that automatically turns on the power when the comparator detects that the output voltage from the integration circuit has become less than or equal to the reference voltage. The broadcast receiver according to claim 1, further comprising a power supply drive circuit that is turned off automatically. (4) The broadcast receiver according to any one of claims (1) to (3), wherein the power switch that is automatically cut off by the automatic power cutoff mechanism is a main power switch. (5) The power switch that is automatically cut off by the automatic power cutoff mechanism is a sub power switch provided at a later stage than the main power switch.
) to (3). (6) The broadcast receiver according to claim (5), wherein the sub power switch is configured to forcibly return to the ON state in conjunction with a cutoff operation of the main power switch. (7) The broadcast receiver according to claim (5), wherein a sub-power switch for remote control is used as the sub-power switch.