| 摘要 |
PURPOSE:To allow television signals of French L system and CC1R.B/G system being received by making a partial oscillator of a tuner to an oscillator for oscillating signals by a higher frequency than a video signal carrier and sound signal carrier always. CONSTITUTION:A system switch 9 is an automatic switching circuit. When said switch 9 is set to the side of a VI, transistors 5 and 7 are conducted to cause tank circuits 1 and 3 to be shorted in terms of high frequency, while tuning can be obtained by a tank circuit 2 (for video signal) of a 34MHz frequency and a tank circuit 4 (for AFT signal) of a 47MHz frequency, consequently, when the switch 9 is set to the VI side, only the band of French L system VI can be received. When the switch 9 is set to the side of a VII.u, transistors 6 and 8 are conducted, and the tank circuits 2 and 4 are shorted in terms of high frequency. Then the tank circuit 1 (for video signal) of a 38.9MHz resonance point and the tank circuit 3 (for AFT signal) are operated, and bands of the French L system VII.u and the CC1R.B/G VI and VII.u can be received.
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