| 摘要 |
PURPOSE:To attain a just tuning in a short time by applying the channel selection of a channel selection control section synchronously with a vertical synchronizing signal so as to form an AFT control signal fetched in the period of the vertical synchronizing signal into the tuning signal. CONSTITUTION:In an electronic equipment provided with an electronic channel selecting device selecting a receiving radio wave, when the electronic channel selector is controlled by using a signal (AFT signal) being the result of frequency detection of a video image intermediate frequency, a channel selection control section comprising a microcomputer or the like fetches the AFT signal within the period of the vertical synchronizing signal to obtain the tuning state of a desired radio wave. That is, a chip selector signal CS is supplied from a master control section (M.CPU) 1 to the tuner control section 10 in the period of the vertical synchronizing signal and the channel selection instruction is supplied synchronously with the vertical synchronizing signal, then the tuner control section 10 applies the tuning operation with an AFT signal with a high detection level at all times.
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