JPS6128451Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a so-called two-screen television receiver that can independently display information from different video sources (different channels, different video signal sources). This invention relates to a two-screen television receiver configured to prioritize display of character signals on the main screen and shift and display the main video signal being received on the sub-screen, and by adopting a configuration that can continuously display received information, The purpose is to increase the usefulness of dual-screen television receivers.

Not limited to this type of two-screen television receiver,
In a normal character multiplex television receiver,
When receiving a text program, the previously received video signal is completely erased, so the video information is forced to be interrupted and important information is missed.

Also, after setting the text multiplex program code and selecting the desired program (that is, after entering the text program receiving mode), it takes, for example, 3 times for the transmission of one program until the selected program is actually displayed. It takes seconds and the number of programs
10, there will be a waiting time of up to 30 seconds, but if the normal TV program is being displayed during that time, is it possible that the receiver is actually working and selecting the text program? However, the problem is that it is difficult to determine whether the device is malfunctioning or not.

In this invention, the time from when the text program code is set until the desired text program that is actually transmitted is selected and displayed is that the text programs that are transmitted sequentially are sequentially displayed on the sub-screen like turning a page. When the desired program for which the program code has been set is transmitted, the content of the text program is displayed on the main screen, and at the same time, the video that was being displayed until then is virtually moved to the sub screen. The above-mentioned drawbacks can be improved by configuring the device to be changed.

Hereinafter, details of the present invention will be explained with reference to drawings showing circuit block diagrams of essential parts.

This two-screen television receiver is comprised of a first television reception system T1, a second television reception system T2, a channel number code exchange circuit B, and a character multiplex receiver R.

The first television reception system T1 includes a first reception block t1 including a varactor tuner, a VIF circuit, and a video detection circuit, and a first electronic channel selection device that, in combination with the varactor tuner, constitutes a PLL or voltage synthesizer type electronic channel selection device. The main components include a circuit P1, a first video signal processing circuit V1, and a first cathode ray tube B1 (for example, a 26-inch CRT) as a display means forming a main screen.

The first video signal processing circuit V1 includes the first video signal processing circuit V1.
The video signal received by the first receiving block t1 is sent to the cathode ray tube B1 or the character multiplex receiver R.
selectively switches and supplies output character signals.

As shown in FIG. 2, the first video signal processing circuit V1 is roughly divided into a first luminance signal processing circuit Y1, a first chrominance signal processing circuit C1, a first matrix circuit M1, and a first video switch S1. be done. Similarly, the second television receiving system T2 includes a varactor tuner, a VIF
A second receiving block t2 including a circuit and a video detection circuit, and a PLL in combination with the varactor tuner.
Alternatively, a second electronic tuning circuit (P2) constituting a voltage synthesizer type electronic tuning device;
The main components include a video signal processing circuit V2 and a second cathode ray tube B2 (for example, a 5-inch CRT) as a display means forming a sub-screen.

The second video signal processing circuit V2 includes the second video signal processing circuit V2.
The video signal received by the second receiving block t2 is sent to the cathode ray tube B2 or the character multiplex receiver R.
selectively switches and supplies output character signals.

As shown in the main circuit diagram of Fig. 2, this second
The video signal processing circuit V2 is roughly divided into a second luminance signal processing circuit Y2, a second chrominance signal processing circuit C2, a second matrix circuit M2, and a second video switch S2. The first or second electronic channel selection circuit P1 or P2 controls a programmable divider in the PLL loop using a binary code corresponding to the channel button selected by the operator, and outputs a predetermined voltage obtained from the comparator. In addition to the usual random access type electronic tuning circuit configuration applied to the varactor tuner, in addition to the binary code conversion circuit E for the programmable divider set corresponding to the channel being received in one reception block, The frequency dividing ratio of the programmable divider of the PLL circuit in the other channel selection circuit is set by the binary code, and this programmable divider is controlled, and the other varactor tuner is set to receive the channel corresponding to this binary code. The structure shall be such that it can be set. The channel code conversion circuit E is operated by a C signal, which will be described later, supplied from the teletext receiver, and is operated by the first electronic channel selection circuit P.
1 channel code (binary code that sets the programmable divider in the PLL circuit) and latches it as necessary to set the division ratio of the programmable divider in the PLL circuit in the second electronic tuning circuit P2. setting so that the second receiving block t2 receives the channel that the first receiving block t1 was receiving immediately before, and at the same time connects the channel that the first receiving block t1 was receiving immediately before
The channel code of the electronic tuning circuit P2 (binary code for setting the programmable divider in the PLL circuit) is received and latched, and the division ratio of the programmable divider of the PLL circuit in the first electronic tuning circuit P1 is determined. The first receiving block t1 is connected to receive the channel that the second receiving block t2 was receiving immediately before the C signal was generated.

The text multiplex receiver R can have a well-known configuration and will not be described in detail, but it is set by a pulse generated upon completion of inputting a program code for receiving a text program, and a desired program is selected. Time t
0, that is, the input program code and the program code in the character information transmitted on the 20th line match.
1, the first control signal W is generated during the period t1, and the first control signal W is generated at time t1.
An attached circuit is provided to continue receiving the text program from the point in time and generate the second control signal C.

With such a configuration, under normal conditions, the first
The cathode ray tube B1 projects the video signal from the first receiving block, and the second cathode ray tube B2 projects the video signal from the second receiving block. Next, when a desired program code is input into the character multiplex receiver R and the receiver is set to receive mode, the first control signal W is supplied from the receiver R to the second video signal processing circuit V2. This first control signal W switches the second video switcher S2, which is an electronic switch, to the position indicated by the dotted line, and inputs the character signals sequentially output from the character multiplex receiver R to the second matrix circuit M2. The character information that is sent out one after another is displayed on the second cathode ray tube B2 in the same way as when turning a page. That is, at this point, the character multiplex receiver R is
The second reception block t2 sequentially reads the character code group inserted in the 20th line of the channel television signal received and converts it into a character signal (video signal displayed as predetermined characters on the cathode ray tube). and is supplied to the second video signal processing circuit V2.

Next, at time t1, when the input program code and the program code in the transmitted text information match, the text multiplex receiver R outputs a second control signal C and moves the first video switch S1 to the position indicated by the broken line. From then on, only the text information of the selected text program is read until another program is selected, and the text information is sent to the first video signal processing circuit V through the signal path L as a text signal.
Supply to 1.

With the generation of the negative output of the second control signal C and the disappearance of the first control signal W, the second video switch S2 switches to the solid line position. At the same time, the second control signal C operates the channel code conversion circuit E, and converts the binary code for setting the programmable divider of the channel received by the first reception block t1 via this circuit to the second reception block. The signal is supplied to the programmable divider of the PLL circuit during t2 to connect the channel that the first receiving block t1 was receiving until then to be received by the second receiving block t2. Therefore,
The video signal of that channel is displayed on the second cathode ray tube B2, and the content of the selected text program is displayed on the main screen of the first cathode ray tube B1.

Since the present invention has the above-described configuration, it can improve all the drawbacks of the conventional example mentioned above.

It goes without saying that the present invention can also be applied to the case where the main and sub screens are configured on the same cathode ray tube.

[Brief explanation of drawings]

FIG. 1 is a circuit block diagram of a two-screen television receiver according to the present invention, and FIG. 2 is a block diagram of the main parts. t1...first television reception system, t2
...Second television reception system, V1...First video signal processing circuit, V2...Second video signal processing circuit, R...Teletext broadcasting receiver, E...Channel code exchange circuit.

Claims (1)

[Scope of utility model registration request] A video signal processing circuit each comprising a channel selection circuit, a television tuner, a video intermediate frequency amplification and detection circuit, an electronic switch for switching and inputting the output video signal of the detection circuit and the character signal, and This occurs when the first and second television receiving systems are equipped with display means for displaying images or text information, and the program code or text program reception mode is set, and the set text broadcast program is selected. a first control signal that disappears at a point in time, and a first control signal that occurs at a point in time when a set program is selected;
A second control signal that continues while the program is being received and all character signal outputs received from the time when the program code is set are input to at least one of the video signal processing circuits of the first and second television reception systems. a teletext receiver comprising a circuit; and controlling an electronic switch in a video signal processing circuit of either the first or second television receiving system using the first control signal to send the character signal to the video display means. The electronic switch in the other video signal processing circuit of the first and second television reception systems is controlled by the circuit connection for page turning display and the second control signal to transmit the selected character signal to the corresponding video display means. The channel code conversion circuit, etc. is controlled by the circuit connection to be displayed and the second control signal, and the channel selection information of the tuner that was supplying reception information to the other video signal processing circuit immediately before the generation of the second control signal is transmitted to one of the abovementioned channels. A dual-screen television receiver comprising, in addition to a tuner supplying received information to a video signal processing circuit of the other side, a circuit connection for adding the received signal to one of the video signals.