The present invention has multiple AV/S terminals, an RF modulator, a S/AV signal converter and multiple switches. The switches connect the AV/S terminals with the RF outputs to allow the AV/S signal from the special AV/S terminal input into the RF modulator to be converted to an RF-signal input to the ANT terminal of the TV. Besides, the present invention further has an ANT input with an electronic switch and a detecting unit having a driver, which decides whether the electronic switch turns on. If the detecting unit detects no AV-signal or S-signal input from the AV/S terminals, the detecting unit first cuts off the power to the RF modulator and then makes the electronic switch turn on. The RF-signal from the ANT input is output to the RF output.

A video processing circuit for receiving a video signal from a tuner or a video recording/reproducing apparatus through a first or second input terminal and for outputting the video signal as it is through an output terminal under one condition and outputting a character signal from a signal source thereof instead of the video signal through the output terminal or outputting the video signal with the character signal superimposed thereon from the output terminal under the other condition. In the video processing circuit, among a plurality of circuits interposing from the first and second input terminals to the output terminal, only circuits related to the signal source of the character signal are formed in one integrated circuit (second integrated circuit) and the other circuits are formed in the other integrated circuit (first integrated circuit).

A video processing circuit for receiving a video signal from a tuner or a video recording/reproducing apparatus through a first or second input terminal and for outputting the video signal as it is through an output terminal under one condition and outputting a character signal from a signal source thereof instead of the video signal through the output terminal or outputting the video signal with the character signal superimposed thereon from the output terminal under the other condition. In the video processing circuit, among a plurality of circuits interposing from the first and second input terminals to the output terminal, only circuits related to the signal source of the character signal are formed in one integrated circuit (second integrated circuit) and the other circuits are formed in the other integrated circuit (first integrated circuit).

Disclosed are a method and apparatus of processing input signals of a display appliance having a plurality of external input terminals and connected to a set top box with a plurality of external input terminals. The method comprises the steps of: detecting a connecting state to the set top box, a signal receiving state from the set top box, a signal receiving state via the external input terminals of the display appliance; selecting and outputting any one of signals supplied from the set top box and signals supplied via external input terminals of the display appliance; and during outputting the selected signal, if a user requests to output a signal inputted from any one of external input terminals of the set top box and the display appliance, selecting and outputting the selected signal.

Systems and methods for use in interconnecting consumer electronic devices in an entertainment system that allow for switching between composite video and S-video formats. The systems and methods support left audio, right audio, and can be selectively adapted to support either composite video or S-video signal formats. The systems and methods further allow for a determination that a consumer electronic device is connected, the type of device that is connected, and the type of signal format that is being utilized for the transmission.