JP3409550B2 - Television receiver with built-in VTR - Google Patents

Description

Description: BACKGROUND OF THE INVENTION [0001] 1. Field of the Invention [0002] The present invention relates to a television receiver with a built-in video tape recorder (VTR), and more particularly to a television compatible with wide broadcasting. The present invention is characterized in that a noise component induced in a sound reproducing head of a VTR is reduced and removed by a magnetic flux leaking from a vertical deflection yoke of a John receiver. 2. Description of the Related Art Conventionally, in a television receiver with a built-in VTR, as shown in FIG. 2, during reproduction of the VTR, a vertical deflection yoke 4 of the television receiver is attached to a reproduction head 1 of the sound. In order to reduce the vertical deflection frequency interference sound induced by the magnetic flux leaked from the coil, a coil 2 in which noise of the opposite polarity is induced is inserted in series with the reproducing head 1, and a reproduced signal without noise is reproduced by the reproducing amplifier 3. Amplifying. [0003] By the way, recently, television broadcasting has been wide-broadcasted and has an aspect ratio of one.
In order to view both the 6: 9 wide broadcast and the 4: 3 normal broadcast, it is necessary to change the deflection angle.
However, when the screen size is switched, the amount of magnetic flux leaking from the vertical deflection yoke changes. Therefore, in a television receiver having a built-in VTR as described above,
Switching the screen size changes the noise applied to the reproducing head, and this measure must be taken. SUMMARY OF THE INVENTION In order to solve this problem, the present invention provides a method for reproducing a sound from a coil in order to cancel a noise component induced in a sound reproducing head by a magnetic flux leaking from a vertical deflection yoke. It is connected in series to the head to change its inductance value. [0005] Thus, when the screen size is switched during the reproduction of the VTR, a reproduced sound with less noise can be obtained. According to the first aspect of the present invention, when an aspect ratio of a screen is switched by changing a current flowing through a vertical deflection yoke, the current from the vertical deflection yoke is changed. In order to cancel noise components of different magnitudes, which are induced in the audio reproducing head by the leakage magnetic flux, a coil in which noise having a polarity opposite to that of the noise component is induced is connected in series to the audio reproducing head, and It is characterized in that the inductance value is changed according to the current flowing through the deflection yoke, so that even if the screen size is switched during the reproduction of the VTR, sound without vertical deflection frequency interference sound can be reproduced. (Embodiment 1) An embodiment of the invention described in claim 1 of the present invention will be described below with reference to FIG. The difference from the conventional example shown in FIG.
, A coil 5 is provided in series, and a switch 6 is provided in parallel with the coil 5. By opening and closing the switch 6, the inductance value of a coil connected in series to the regenerative amplifier 3 is changed. According to this configuration, if an optimum inductance value is selected for the deflection current flowing through the vertical deflection yoke 4 which changes due to the switching of the aspect ratio, noises of different magnitudes induced in the reproducing head 1 are selected. The component can be removed, and sound reproduction without vertical deflection frequency interference sound can be expected. Although the inductance value is changed by the coil 5 and the switch 6 in the above description, a configuration in which a switching is provided by providing a regenerative amplifier and a plurality of coils connected in series to the regenerative amplifier is also possible. As described above, according to the present invention, it is possible to realize the reproduction of the sound from which the vertical deflection frequency interference sound has been removed irrespective of the current flowing through the vertical deflection yoke due to the change in the screen size of the television. be able to.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram of a television receiver with a built-in VTR according to an embodiment of the present invention; FIG. 2 is a block diagram of a conventional television receiver with a built-in VTR; Reference Signs List 1 playback head 2, 5 coil 3 playback amplifier 4 vertical deflection yoke 6 switch

Continuation of the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) H04N 5/765 H04N 5/91-5/956 G11B 33/06

Claims (1)

(57) [Claim 1] When an aspect ratio of a screen is switched by changing a current flowing through a vertical deflection yoke,
In order to cancel noise components of different magnitudes, which are induced in the audio reproducing head by the leakage magnetic flux from the vertical deflection yoke, a coil in which noise having a polarity opposite to that of the noise component is induced is connected in series to the audio reproducing head. And a VTR with a built-in VTR, wherein the inductance value is changed according to a current flowing through the vertical deflection yoke.