Sharp Kabushiki Kaisha Corporation

Kazuhiro Nakai

Takao Abumi

Nobuo Minoura

Isao Matsumura

Yasukazu Yoshinaga

An automatic tuning scheme for use in TV receivers includes a start/stop circuit which creates a search start signal and a search stop signal upon the receipt of a search start instruction and a detected incoming signal, respectively, a tuning voltage generator which generates a gradually varying tuning voltage under control of the search start signal and search stop signal, and a memory circuit for storing the tuning voltage from the generator when desired. The tuning voltage stored in the memory circuit is supplied to a tuner including a well known voltage-sensitive capacitance diode.

Automatic pre-programming system for TV receivers

A television signal determination circuit is associated with an automatic tuning system, which automatically tunes a television set to local channels, in order to determine whether received signals are desired television signals. The television signal determination circuit comprises a first counter means for counting received synchronizing signals for a predetermined period of time, a second counter means for counting reference clock signals for the predetermined period of time, and a determination means for determining whether the synchronizing signals are received by a predetermined number within the predetermined period of time by comparing output signals from the first and second counter means.

Growing community of inventors

Ikoma, Japan

Kazuhiro Nakai