Hitachi, Ltd.

Kiyoshi Fushimi

Keizo Shimizu

An indication system for a television receiver displays a receiving channel number directly from a local oscillation signal of the turner and a signal showing the receiving band associated with the operation of the tuner. An initial value signal is generated from the signal showing the receiving band. The value of the initial value signal is subtracted from the result of counting the local oscillation signal for a predetermined length of time. The resulting difference is divided into six parts, thus producing a pulse signal coincident with the receiving channel number which is to be displayed on an indicator.

Receiving channel number indication system for television receiver

When a receiving channel of television broadcast is selected by the frequency sweep, a video carrier and an audio carrier appear alternately at an output of an intermediate frequency (IF) stage. A channel selection system is disclosed, which distinguishes the video carrier and the audio carrier from each other by the presence or absence of a sync. separation pulse during the frequency sweep, in which a sync. pulse is distinguished from a noise pulse by the presence or absence of a horizontal flyback pulse and the video carrier is distinguished from the audio carrier in response to the presence or absence of the sync. pulse to selectively stop the sweep.

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Yokohama, Japan

Kiyoshi Fushimi