| 摘要 |
PURPOSE:To operate the circuit accurately and independently of the state of electric field and to make the operation easy, by presetting channel through rise and fall of tuning voltage through the operation of the 1st and 2nd frequency sweep switches. CONSTITUTION:When the channel A is preset, the channel selection button A is first depressed. Then, either one of the frequency sweep switch 5 or 6 is depressed and the tuning voltage is swept toward either high or low direction. Thus, when the broadcast signal of the channel A is started to be received, the IC terminal 18 is at low level with the synchronizing signal applied to the terminal 15 to delay the sweep of the tuning voltage of IC1. In this case, the switch 5 or 6 is released when the state of picture is the best after reaching the normal tuning point to stop the sweep of the tuning voltage. Further, when other channel selection button is depressed, the tuning voltage corresponding to the channel A is stored in the memory IC2. Further, when a channel is skipped, the switch 19 for unnecessary station skip is depressed. |
