Channel display device for receivable channels

Claim 1

A channel display device for indicating a signal-receiving state of a plurality of television channels, each channel having a respective given carrier frequency and channel number, in response to a determination as to whether or not each channel is signal receivable, the channel display device comprising: on-screen means having a video RAM in which character codes corresponding to the channel numbers of all television broadcast channels are written at addresses corresponding to display positions of the channel numbers, and for displaying a list of the television broadcast channel numbers on a TV screen in response to data read out of the video RAM; memory means for storing data showing channel numbers and address data of the video RAM corresponding to the channel numbers when determining whether or not a channel number selected among the list of all channel numbers displayed on the TV screen is signal receivable; first means for storing first attribute data in a predetermined address in the video RAM in response to the address data of the video RAM corresponding to a channel number stored in the memory means, said first attribute data showing that a channel is undergoing a determination as to whether the channel is signal receivable or not; tuning means for detecting whether or not a channel at a given carrier frequency is signal receivable in response to channel number data stored in the memory means, and for generating a tuning signal showing that the channel is signal receivable, when it is detected that television signals are received at the given carrier frequency; and second means for rewriting, in response to the tuning signal for a channel, the first attribute data stored in the predetermined address of the video RAM into a second attribute data showing that the channel for which the tuning signal is generated is television signal receivable.