KR100257257B1 - Television having a mode transition function - Google Patents

Abstract

PURPOSE: A television receiver having a mode conversion function is provided to convert an operation mode into an RF mode by enabling a user to selectively operate a key in case that an R,G,B signal is applied through a scart jack from a peripheral device. CONSTITUTION: A remote control device enables a user to input a mode conversion signal for converting an operation mode of a TV receiver. A receiving unit receives the mode conversion signal, and converts the signal into an electric signal. A microprocessor outputs a low-level signal or a high-level signal. An inverter is composed of resistances and a transistor. The inverter inverses a level of an FB signal in case that the FB signal is inputted through the scart jack from the peripheral device. A NOR gate receives the signal outputted from the inverter and the signal outputted from the microprocessor.

Description

TV receiver with mode switching

1 is a view for explaining a mandatory mode switching process according to the prior art.

2 is a block diagram of a television receiver having a mode switching function according to an embodiment of the present invention;

* Explanation of symbols for main parts of the drawings

1: antenna 2: tuner

3: IF circuit 4: external device

5: SCART JACK 6: Socket

7: Chroma IC 8: CRT driver

9: CRT 10: Remote Controller

11: receiver 12: microprocessor

13: inverter 14: NOR gate

The present invention relates to a television receiver in which switching to an RF mode is possible according to a user's selective key operation even when an RGB signal is applied from an external device through a scart jack.

Recently, as consumers' tastes have become more advanced, cases of widespread use of television receivers as general media devices rather than simple airwave receivers by connecting audio or other devices to television receivers have become commonplace. In the middle, a 21-pin scart jack for receiving a signal from an external device and a separate socket for connecting the same are being commercialized on the case back of the main body.

1 is a diagram showing the main components of the above-described television receiver, in which, reference numeral 1 is an antenna, and 2 is a tuner for tuning a specific broadcast signal set by a user among broadcast signals received by the antenna. ), 3 is an intermediate frequency circuit (hereinafter referred to as IF circuit) which outputs a composite video signal (CVS) from the broadcast signal tuned by this tuner 1, 4 is an R, G, B signal and External devices that output FB (Fast Blanking) signals, 5 and 6 are used to connect the SCART JACK and the SCART JACK which transmits the R, G, B and FB signals output from the external device 4, respectively. A television receiver (hereinafter referred to as a TV receiver) is a socket provided on the back of the case of the main body.

Reference numeral 7 generates tones (R, G, B) and luminance signals based on the composite video signal output from the IF circuit (3), and R, G, and R from the external device through the scart jack (5). When the B signal and the FB signal are applied, the chroma IC which first processes and outputs the R, G, and B signals output from an external device by forcibly switching to the R, G, and B modes by the FB signal, and the chroma IC (8) A CRT driver for driving the CRT in accordance with the color tone and luminance signal output from 7), and 9 is a CRT driven by this CRT driver.

That is, the conventional TV receiver having the above-described configuration, when the FB signal is applied from the external device 4 together with the R, G, and B signals through the scart jack 5, the operation mode of the chroma IC 7 Is forcibly switched to the R, G, and B modes, so that the R, G, and B signals of the external device 4 applied through the skat jack 5 in preference to the composite video signal output from the IF circuit 3. Is prioritized.

However, in the above-described television receiver, when the signal is switched to the R, G, and B signal processing modes by an external signal through the scart jack 6, the external device in the R, G, and B modes is turned off to switch to the RF mode. OFF) or has to remove the scart jack from the body.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and a television receiver is capable of switching to RF mode according to a user's selective key operation even when an R, G, or B signal is applied from an external device through a skat jack. The purpose is to provide.

A television receiver having a mode switching function according to the present invention for realizing the above object has a socket for connecting a scart jack to a surface of a main body, and is applied through an FB signal output terminal of the scart jack. When the level of this FB signal is the first level according to the input level of the BLANKING signal, the operation mode is switched to the R, G, B mode by an external device, and when the second level is the RF by the received broadcast signal A television receiver having a chroma IC to be switched to a mode, comprising: mode selection means for outputting a switching signal to an R, G, B mode or an RF mode according to a viewer's selection input, and a mode switching signal from the mode selection means Control means for outputting a control signal of the first or second level depending on whether the input, Inverter for inverting the level of the FB signal applied through the scart jack and A NOR gate configured to receive a signal output from the butter and a signal output from the control means and output a signal of the first level to the FB signal input terminal of the chroma IC only when the level of both signals is the second level. Characterized in that configured to include.

According to the present invention having the above-described configuration, even when the R, G, B signals are applied from the external device through the scart jack, the user can change the operation mode of the TV receiver to the RF mode through a separate key operation installed in the remote control device. You can switch.

Hereinafter, an embodiment according to the present invention will be described with reference to the drawings.

FIG. 2 is a block diagram of a television receiver having a mode switching function according to an embodiment of the present invention. In the drawing, the same components as those in FIG.

Reference numeral 10 is a remote control device for the user to input a mode switching signal for switching the operation mode of the TV receiver, 11 receives a mode switching signal of the far-infrared type output from the remote control device 10 and converts it into an electrical signal. The receiving unit 12 outputs a low level control signal based on the FB (FAST BLANKING) signal applied through the skat jack 5 when there is no separate mode switching signal from the receiving unit 11 and to the viewer. Microprocessor as a control means for outputting a high level control signal when a separate mode switching signal is applied, 13 is a general inverter composed of resistors R1, R2, R3 and transistor Q1, When the FB signal is input through the scart jack 5, the level of the FB signal is reversed. Reference numeral 14 is also a NOR gate configured by connecting a collector terminal of another transistor Q2 to an output terminal of a general inverter circuit composed of resistors R4 and R5 and transistor Q3, and the NOR gate 14 is the inverter ( 13 and the signal output from the microprocessor 12, and outputs a high level signal only when the level of both signals is LOW, so that the scart from the chroma IC 7 Outputs the R, G, B signal applied through the jack (5).

Next, the operation of the device having the above configuration will be described.

As described above with reference to FIG. 1, R, G, and B to which a TV receiver is currently applied from an external device 4 by connecting the scart jack 5 to a socket 6 installed on a case back of a TV receiver. In a situation in which the signal is being operated (R, G, B mode), when the viewer inputs a switching signal to the RF mode through the remote control device 10, the receiving unit 11 is switched in the infrared mode. The microprocessor 12 outputs a control signal of a high level regardless of the FB signal applied from the FB terminal of the scart jack 5.

As a result, a high level signal is applied to one of the two input terminals a and b of the NOR gate 14 so that the level of the signal is applied to the remaining terminal b in the logical operation characteristic of the NOR gate. Regardless of whether the low level signal is output from the output terminal of the NOR gate 14, the signal is applied to the chroma IC 7 to switch the operation mode of the entire apparatus to the RF mode. As described above, the chroma IC 7 outputs R, G, and B signals based on the composite video signal output from the IF circuit 3.

That is, according to the above embodiment, even when the TV receiver is operated in the R, G, and B modes, the viewer can switch to the RF mode through key operation of the remote control device.

In addition, the above embodiments may be modified in various ways without departing from the technical spirit of the present invention.

As described above, according to the present invention, even when the R, G, B signals are applied from an external device through the scart jack, it is possible to realize a television receiver which can switch to the RF mode according to the user's selective key operation. do.

Claims (1)

When the level of this signal is the first level according to the input level of the FB (FAST BLANKING) signal applied through the FB signal output terminal of the skat jack, and having a socket for connecting the skat jack on the surface of the main body In the television receiver having a chroma IC which is switched to the R, G, B mode by an external device and the RF mode by the received broadcast signal when the second level is used, Mode selection means for outputting a switching signal to the R, G, B mode or the RF mode, control means for outputting a control signal of the first or second level depending on whether the mode switching signal is input from the mode selection means An inverter for inverting the level of the FB signal applied through the skat jack, and a signal output from the inverter and a signal output from the control means. And a NOR gate configured to output the signal of the first level to the FB signal input terminal of the chroma IC only when the signal levels are all the second level.