JPH0444477A - Television receiver - Google Patents

Abstract

PURPOSE:To realize a television receiver offering accurate audio and video signal reproduction by providing a speaker sounding a sound wave of a horizontal synchronizing signal in opposite phase to that of a sound wave resulting from a deflection coil or the like, a phase correction circuit of the signal and an adjustment mechanism into a cabinet. CONSTITUTION:A speaker 5 sounding a sound resulting from a horizontal synchronizing signal of 15.75kHz and a phase correction circuit 7 with a correction dial 6 mounted thereto are fitted to a ceiling of a cabinet l. A sound wave of l5.75kHz sounded mainly from a deflection coil 4 and a flyback transformer 3 is cancelled by the sound wave of 15.75kHz in opposite phase sounded from the speaker 5 installed on the ceiling of the cabinet 1. Thus, the resonance or beat due to the reproduction sound of a source and the resonance sound resulting from the horizontal synchronizing signal is not caused and then not outputted to the outside of the cabinet l, and accurate audio and video signal reproduction is attained. That is, since the reproduction sound from the source and the resonance sound resulting from the horizontal synchronizing signal do not cause the resonance or beat, the accurate audio and video signal reproduction is implemented.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a television in which unnecessary signal sounds are removed.

(Conventional technique tri> A conventional television will be explained with reference to FIG.

Figure 2 is a side sectional view showing the interior of a conventional television with a part cut away.The cabinet 1 has a cathode ray tube 2 so that the screen appears in the front opening, and a flyback transformer behind it. 3 is placed. The above-mentioned cathode ray tube 2 has a deflection coil 4 attached to its rear end neck.

When the television configured in this manner is operated, a 15.75 kHz sound wave is radiated into the air through the cabinet 1 mainly due to the vibrations of the deflection coil 4 and flyback transformer 3. This sound wave is extremely high-pitched and weak, so it is masked by the television sound, making it difficult to hear.Also, since the television signal only has a frequency band of up to 16 kHz, it has been ignored.

(Problem to be solved by the invention) However, in recent years, the shift to AV has progressed.

With the spread of B-mode satellite broadcasting and digital sound playback of laser discs, it has become possible to play back up to 20°, and the sound played back from the source and the resonance sound of the horizontal synchronization signal cause resonance and beats, making it difficult to accurately reproduce the sound. There was a problem that AV playback was not possible. As a countermeasure, the resonance sound of the horizontal synchronization signal can be reduced by wrapping the deflection coil 4 and the flyback transformer 3 in sound-absorbing material or using a vibration-proof structure, but this is difficult because they are high-voltage parts.

The present invention solves the above problem, and provides a television that performs accurate AV reproduction in which the sound reproduced from the source and the resonance sound of the horizontal synchronization signal do not cause resonance or buzzing, except for the resonance sound of the horizontal synchronization signal. It provides:

(Means for Solving the Problems) In order to solve the above problems, the present invention provides a horizontal synchronization signal of 15.75 kHz which is in opposite phase to the 15.75 kHz sound waves emitted by a deflection coil, flyback transformer, etc. The cabinet includes a speaker that generates sound waves, a phase correction circuit for the signal, and an adjustment mechanism.

(Function) With the above configuration, the 15.75 kHz sound waves mainly generated by the deflection coil 4 and flyback transformer 3 are as follows.

The waves are canceled by the opposite phase 15.75 kHz sound waves generated from the speakers installed in the cabinet and are not radiated into the air.

(Example) An example of the present invention will be described with reference to the sectional view of FIG. In the figure, the difference between this embodiment and the conventional example shown in FIG. 2 is that a horizontal synchronizing signal 15.
A speaker 5 that generates 75 kHz and a phase correction circuit 7 equipped with a correction dial 6 are installed. Since the rest is the same as the conventional example, the same components are given the same reference numerals and their explanations will be omitted.

The operation of the television configured as above will be explained.

The 15.75 kHz sound waves mainly generated by the deflection coil 4 and the flyback transformer 3 are the opposite-phase 15.7 kHz sound waves generated from the speaker 5 installed on the ceiling of the cabinet 1.
It is canceled out by the 5 kHz sound wave, and does not go out of the cabinet 1 without causing any resonance or buzzing due to the resonance sound of the playback sound from the source and the horizontal synchronization signal, and it is possible to obtain accurate A.
V playback is possible.

As described above, according to this embodiment, accurate AV reproduction is possible because the reproduced sound from the source and the resonance sound of the horizontal synchronization signal do not resonate or beat. In this embodiment, one speaker 5 is used, but it goes without saying that a plurality of speakers 5 may be used, and that the phase correction circuit 7 and the adjustment mechanism may be linked with the AFC circuit for the horizontal synchronization signal.

(Effects of the Invention) As explained above, according to the present invention, a speaker that generates a horizontal synchronization signal of 15.75 kHz sound wave having a phase opposite to a 15.75 kHz sound wave emitted by a deflection coil, flyback transformer, etc. By equipping the cabinet with a phase correction circuit and adjustment mechanism for the signal, the 15.7
A 5 kHz sound wave has an opposite phase sound wave of 15.75 kHz
The result is a television that is canceled out by the sound waves from outside the cabinet and provides accurate AV playback. Therefore, it is possible to accurately enjoy the B mode of satellite broadcasting and digital sound reproduction of laser discs.

[Brief explanation of drawings]

FIG. 1 is a side sectional view of a television according to the present invention, and FIG.
The figure is a side sectional view of a conventional television. 1... cabinet, 2... cathode ray tube,
3... Flyback transformer, 4... Deflection coil, 5... Speaker, 6... Correction dial, 7... Phase correction circuit. Patent applicant Matsushita Electric Industrial Co., Ltd.

Claims (1)

[Claims] 15. Emitted by deflection coils, flyback transformers, etc.
75kHz sound wave and opposite phase horizontal synchronization signal 15.75k
A television comprising a speaker that generates Hz sound waves, a phase correction circuit for the signal, and an adjustment mechanism in a cabinet.