JPS6184190A - Television receiver - Google Patents

Abstract

PURPOSE:To suppress the deterioration of a reproduction signal by supplying directly chrominance and luminance signals supplied to a mixer circuit in a video tape recorder to a video chroma process circuit for forming a signal for driving an image receiving tube. CONSTITUTION:A changeover switch 23a switches a signal line so that either one of a luminance signal from a luminance/chromaticity separator circuit 5 and that from a luminance signal processing circuit 11 is selectively supplied to a video chroma process circuit 7. A changeover switch 23b switches the signal line so that either one of a chromaticity signal from the circuit 5 and that from a chromaticity signal processing circuit 12 is selectively supplied to the circuit 7. Thus the luminance signal demodulated by the circuit 11 and the chromaticity signal subjected to the frequency conversion by the circuit 12 are directly supplied to the circuit 7 without passing through a mixer circuit 13 and the circuit 5. Accordingly the signal route of a television receiver 21 is shortened by route as is found unnecessary in such a way compared with a conventional one, and thus the signal deterioration can be suppressed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a television receiver in which the image quality of a reproduced video signal is improved by shortening the signal path.

[Conventional technology]

2. Description of the Related Art A television receiver with an integrated video tape recorder is known, in which a video tape recorder is built into the television receiver. A conventional television receiver 1 of this kind shown in FIG. 2 is roughly composed of a receiver body 2 and a video tape recorder 3. As shown in FIG. The receiver body 2 includes a changeover switch 4 and a luminance/chromaticity separation circuit 5 such as a comb filter that separates luminance signals and chromaticity signals from the supplied composite video signal.
The luminance and chromaticity signals separated by the luminance and chromaticity separation circuit 5 are supplied to the video chroma process circuit 7 and the image receiver, which form three primary color video signals of red, green, and blue necessary for driving the picture tube 6. Pipe 6 etc. constitute the main components.

The video tape recorder 3 includes a reproduction amplifier circuit 1 that amplifies the signal read from the magnetic tape 9 by the rotating magnetic head 8.
0, a luminance signal processing circuit 11 that demodulates the frequency modulated luminance signal from the reproduction amplifier circuit 10, and a reproduction amplifier circuit 10.
The center frequency is 158MHz.
The main components include a chromaticity signal processing circuit 12 that converts into a chromaticity signal, a mixing circuit 13 that mixes the output of the luminance signal processing circuit 11 and the output of the chromaticity signal processing circuit 12, and the like.

The video tape recorder 3 and the receiver body 2 are connected to a mixing circuit 1
3 and the luminance/chromaticity separation circuit 5 are integrated by connecting them via a changeover switch 4. By switching the changeover switch 4, the video signal from the built-in tuner, external video tape recorder, etc. and the built-in video Video signals from the tape recorder 3 can be switched.

[Problem that the invention seeks to solve]

In the conventional television receiver 1 described above, when the video reproduced by the built-in video tape recorder 3 is displayed on the picture tube 6, the luminance signal demodulated by the luminance signal processing circuit 11 is also
The chromaticity signal frequency-converted in the chromaticity signal processing circuit 12 is also mixed in the mixing circuit 13 and then separated in the luminance/chromaticity separation circuit 5. Signal processing is added to convert the signals back into separate signals. For this reason, although a signal processing process such as mixing and separation is obtained that apparently does not involve a change in the signal, there are problems in that the signal actually deteriorates.

[Means for Solving the Problems] This invention solves the above problems, and separates a video signal read from a magnetic tape into a luminance signal and a chromaticity signal, and performs predetermined signal processing on each. A television receiver having a built-in video tape recorder which is then mixed in a mixing circuit, wherein a luminance signal and a chromaticity signal supplied to the mixing circuit in the video tape recorder are used to form a signal for driving a picture tube. The gist of this invention is to provide a means for directly supplying the video chroma processing circuit.

[Effect]

When displaying a playback signal from a built-in video tape recorder, the present invention directly converts the luminance signal and chromaticity signal supplied to the mixing circuit in the video tape recorder to the video tape recorder.
Supplies the chroma process circuit.

〔Example〕

Hereinafter, embodiments of the present invention will be described with reference to FIG. FIG. 1 is a schematic circuit diagram showing an embodiment of the television receiver of the present invention. In addition, in Figure 1,
Components that are the same as those in FIG. 2 are given the same reference numerals.

In FIG. 1, a television receiver 21 has a receiver main body 22.
A switch circuit 23 is provided between the luminance/chromaticity separation circuit 5 and the video/chroma process circuit 7, and the changeover switch 4 is omitted. The switch circuit 23 has a changeover switch 23a, 23b provided in a luminance signal line 24 and a chromaticity signal line 25, and both changeover switches 23a, 23b can be switched in conjunction with each other.

The changeover switch 23a switches the signal line to selectively supply one of the luminance signal from the luminance/chromaticity separation circuit 5 and the luminance signal from the luminance signal processing circuit 11 to the video/chroma processing circuit 7. . Further, the changeover switch 23b selectively supplies one of the chromaticity signal from the luminance/chromaticity separation circuit 5 and the chromaticity signal from the chromaticity signal processing circuit 12 to the video/chroma processing circuit 7. , switch the signal line.

Here, if the video reproduced by the video tape recorder 3 integrated in the receiver main body 22 is to be displayed on the picture tube 6, the changeover switches 23a and 231) of the switch circuit 23 are both switched to the video tape recorder 3 side as shown in the figure. . As a result, the video tape recorder 3 and the receiver body 2
2, the luminance signal processing circuit 11 and the chromaticity signal processing circuit 12 are connected to the video/chroma processing circuit 7.

Therefore, the luminance signal demodulated by the luminance signal processing circuit 11 and the chromaticity signal frequency-converted by the chromaticity signal processing circuit 12 are directly transmitted without passing through the mixing circuit 13 and the luminance/chromaticity separation circuit 5. The signal is supplied to a video chroma processing circuit 7.

Therefore, in the television receiver 21, the signal path is shorter than that of the conventional television receiver 1 because the signal does not pass through the mixing circuit 13 and the luminance/chromaticity separation circuit 5, and signal deterioration can be suppressed.

Note that when displaying a television signal received by an antenna output from a built-in tuner on the picture tube 6, or when displaying a playback signal from a video tape recorder (not shown) external to the television receiver 21, , the changeover switch 23a123b in the switch circuit 23,
It is preferable to switch to the luminance/chromaticity separation circuit 5 side.

In this way, when the television receiver 21 displays a signal reproduced by the built-in video tape recorder 3, the television receiver 21 directly converts the luminance signal and chromaticity signal supplied to the mixing circuit 13 in the video tape recorder 3 into a video chroma signal. Since the configuration is such that the signal is supplied to the process circuit 7, compared to the conventional configuration in which the signal is supplied to the video/chroma process circuit 7 via the mixing circuit 13 and the luminance/chromaticity separation circuit, the mixing circuit 13 and the luminance/chromaticity separation circuit are 5 can be omitted, image quality can be improved accordingly, and the significance of integrating the video tape recorder 3 into the receiver main body 22 can be increased.

〔Effect of the invention〕

As explained above, according to the present invention, when displaying a playback signal from a built-in video tape recorder, the luminance signal and chromaticity signal supplied to the mixing circuit in the video tape recorder are directly sent to the video chroma processing circuit. Compared to the conventional configuration in which the signal is supplied to the video/chroma processing circuit via the mixing circuit and the luminance/chromaticity separation circuit, the signal path passing through the mixing circuit and the luminance/chromaticity separation circuit is This can be omitted, the image quality can be improved accordingly, and the significance of integrating the video tape recorder into the receiver main body can be increased.

[Brief explanation of drawings]

FIG. 1 is a schematic circuit diagram showing an embodiment of a television receiver of the present invention, and FIG. 2 is a schematic circuit diagram showing an example of a conventional television receiver. 3... Video tape recorder, 5... Luminance/chromaticity separation circuit, 6... Picture tube, 7... Video/chroma process circuit, 11... Luminance signal processing circuit, 12... Color degree signal processing circuit, 21...television receiver, 22
...Receiver body, 23...Switch circuit.

Claims (1)

[Claims] The television receiver is equipped with a built-in video tape recorder that separates a video signal read from a magnetic tape into a luminance signal and a chromaticity signal, performs predetermined signal processing on each signal, and then mixes the video signal in a mixing circuit. A television receiver comprising means for directly supplying luminance signals and chromaticity signals supplied to a mixing circuit in a tape recorder to a video chroma processing circuit that forms signals for driving a picture tube.