JPH05292410A - High-vision receiver - Google Patents

Abstract

PURPOSE:To connect a MUSE decoder outside without considerably increasing the number of terminals by using the decoder video signal output terminal of the conventional high-vision receiver for both of inputs and outputs and providing a changeover switch. CONSTITUTION:This device is provided with an AFC pulse input terminal 16, AFC pulse detection circuit 17 to automatically detect AFC pulses, input/output changeover switch 12, input/output discriminating circuit 18 to discriminate and switch signals from these two circuits, and video signal switching circuit 11 and corresponding to a signal from the input/output discriminating circuit, a decoder input/output circuit switches video signals from an inside simplified MUSE decoder 10 and an outside MUSE decoder 1 and impresses those video signals to a signal processing circuit 9.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a decoder input / output circuit for a high-definition television receiver (hereinafter referred to as a high-definition receiver) having a built-in simple MUSE decoder.

[0002]

2. Description of the Related Art In a conventional high-definition receiver with a built-in MUSE decoder, since the band of the video signal of the MUSE decoder is higher than that of the simple MUSE decoder, it is not necessary to purposely provide an external MUSE decoder input terminal.

Decoder-related terminals of a conventional high definition receiver with a built-in MUSE decoder will be described below with reference to FIG. As shown in FIG. 4, the decoder-related terminals are video output terminals 2, 3, 4 and audio output terminals 5, 6, 7,
It has only 8 output terminals and no input terminals.

[0004]

However, in the above configuration, when the built-in decoder is the simple MUSE decoder, the band of the video signal of the simple MUSE decoder does not reach the band of the video signal of the MUSE decoder.
It is inferior in terms of image quality. Further, since there is no decoder input terminal, there is a drawback that the MUSE decoder cannot be connected to the outside.

In view of the above drawbacks, it is an object of the present invention to connect the MUSE decoder to the outside without increasing the number of terminals by using the video signal output terminal of the decoder as an input / output terminal.

[0006]

In order to solve the above problems, a decoder input / output circuit for a high-definition receiver according to the present invention uses a decoder video output terminal of a conventional high-definition receiver as an input / output and a user switches a switch. This allows the MUSE decoder to be connected to the outside.

According to a second aspect of the present invention, the automatic frequency control (Autom) is provided as in the configuration of the high-definition receiver.
Attic Frequency Control (hereinafter referred to as AFC) When the video signal from the external MUSE decoder is not input even when the user switches to external input by combining the pulse input terminal, the detection circuit, and the input / output determination circuit, that is, the external MUSE This is a high-definition receiver having a decoder input / output circuit that can automatically switch to the image of the built-in simplified MUSE decoder when an AFC pulse from the decoder is not detected.

According to the invention of claim 3, in the receiver main body,
This is for the case where there is a MUSE signal input terminal and also has a sub-screen function, and during normal MUSE reception, a simplified MUSE decoder or an AFC from the MUSE decoder
Since the pulse is given to the BS tuner, the movement of the BS tuner is restricted.
By combining the E signal input terminal, the AFC pulse switching circuit, and the control circuit, when the image from the MUSE signal source is displayed on the main screen, the image of the built-in simple type MUSE decoder is used, and the simple type MUSE decoder By stopping the AFC pulse with the AFC pulse switching circuit, by freeing the movement of the BS tuner,
The NTSC output of the BS tuner is displayed on the child screen or the parent and child display can be reversed.

[0009]

The present invention has the above-mentioned configuration and is of a simplified type MUSE.
It is possible to connect a MUSE decoder to the outside without greatly increasing the number of terminals in the HDTV receiver with a built-in decoder.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. The same reference numerals and parts or means shown in FIGS. 1, 2, 3, and 4 indicate the same parts.

(First Embodiment) FIG. 1 is a block diagram showing a first embodiment of the present invention. Simple MUSE decoder 1
When the input / output switch 12 is set to output the video signal A from 0, the signal processing circuit 9 and the video input / output terminal 1 are passed through the bidirectional video signal switching circuit 11.
It is output to 3, 14, and 15. The MUSE decoder 1 external to the HDTV receiver has video input / output terminals 13 and 14,
If it is connected to 15, the video signal switching circuit 11 is switched by setting the user input / output selector switch 12 to the input side, and the signal of the MUSE decoder 1 is input to the signal processing circuit 9. ..

(Embodiment 2) Next, an embodiment of the second invention of the present invention will be described with reference to FIG.

In FIG. 2, in addition to the configuration of FIG. 1, an input / output discrimination circuit is added between the input / output changeover switch 12 and the video signal changeover circuit 11, and an AFC pulse input terminal 16 and an AFC pulse detection circuit 17 are provided. Is added. The AFC pulse detection signal from the MUSE decoder 1 outside the HDTV receiver and the signal from the input / output selector switch 12 are discriminated by the input / output discriminating circuit 18, so that the input / output selector switch 12 is on the input side. A due to the power being off, etc.
Built-in simplified MUS when FC pulse is not detected
The video signal from the E decoder 10 can be given priority to the signal processing circuit 9.

(Embodiment 3) Next, an embodiment of the third invention of the present invention will be described with reference to FIG.

3 is different from that of FIG. 2 in that
The MUSE signal input terminal 19, the AFC pulse switching circuit 20, and the control circuit 21 are added, and the control signal from the control circuit 21 is also input to the input / output determination circuit 18. This corresponds to the case where the receiver has the MUSE signal input terminal 19 and the sub-screen function.
When a signal from a MUSE signal source such as an EVTR is displayed on the screen, a control signal is supplied from the control circuit 21 to the input / output determination circuit 18 in order to use the simplified MUSE decoder 10, and the video signal from the simplified MUSE decoder 10 is processed. Circuit 9
It is forcibly switched to give to. At this time, the AFC pulse is output from the simplified MUSE decoder, but if this is given to the BS tuner 22, its movement is restricted, and the NTSC output of the BS cannot be displayed on the inset screen. This is prevented. Therefore, the AFC pulse switching circuit 20 forcibly stops the AFC pulse and frees the movement of the BS tuner. This is the same when the parent and child screens are reversed.

[0016]

The present invention has the above-described structure and is of a simplified type M
It is possible to connect the MUSE decoder to the outside without greatly increasing the number of terminals in the HDTV receiver with a built-in USE decoder.

[Brief description of drawings]

FIG. 1 is a block diagram of a decoder input / output circuit of a high-definition receiver according to an embodiment of the present invention.

FIG. 2 is a block diagram of a decoder input / output circuit of a high-definition receiver in one embodiment of the second invention of the present invention.

FIG. 3 is a block diagram of a decoder input / output circuit of a high-definition receiver in one embodiment of the third invention of the present invention.

FIG. 4 is a block diagram of a video and audio output unit of a conventional high-definition receiver.

[Explanation of symbols]

 1 MUSE Decoder 10 Simple MUSE Decoder 11 Video Signal Switching Circuit 12 Input / Output Changeover Switch 16 AFC Pulse Input Terminal 17 AFC Pulse Detection Circuit 18 Input / Output Discrimination Circuit

Claims (3)

[Claims] 1. A video signal changeover circuit and an input / output changeover switch are provided, and a video signal of an internal simplified MUSE decoder and an external MUSE decoder is changed over by a signal of the changeover switch, and the video is outputted to a signal processing circuit. A high-definition receiver equipped with a decoder input / output circuit that gives signals. 2. An AFC pulse input terminal, an AFC pulse detection circuit that detects a pulse, an input / output changeover switch, and an input / output determination circuit that determines and switches a signal from the AFC pulse detection circuit or the input / output changeover switch. A decoder input / output having a video signal switching circuit, which switches between a video signal of an internal simplified MUSE decoder and an external MUSE decoder according to a signal from the input / output determination circuit, and supplies the video signal to a signal processing circuit. HDTV receiver with circuit. 3. An AFC pulse input terminal, an AFC pulse detection circuit for detecting a pulse, an input / output changeover switch, and an input / output discrimination circuit for discriminating and switching a signal from the AFC pulse detection circuit or the input / output changeover switch. , A video signal switching circuit, a MUSE signal input terminal, an AFC pulse switching circuit, and a control circuit, and an internal simplified MU is provided by a signal from the input / output determination circuit.
The SE decoder and the video signal of the external MUSE decoder are switched, the video signal is given to the signal processing circuit, and AF is performed by signals from the input / output determination circuit and the control circuit.
A high-definition receiver equipped with a decoder input / output circuit that can also switch C pulses to the BS tuner.