| 摘要 |
PURPOSE:To prevent the output signal of a sound modulator from being deteriorated in a transmission passage and a receiver by frequency-converting the output signal of the sound modulator within the period of a timing signal. CONSTITUTION:An image carrier wave (b) is modulated in an image modulator 1 by a video base band signal (a) and an output signal (c) of an image modulator is FM modulated by an image FM modulator 11 during a synchronizing signal period in which a gate signal generator 5 generates a gate signal, converted into a higher frequency or a lower frequency than the image carrier wave to output an output signal (j) of the image FM modulator. A sound carrier wave (f) is modulated in a sound modulator 3 by a sound base band signal (e), an output signal (c) of the sound modulator is FM modulated by a sound FM modulator 12 during a timing signal period in which the gate signal generator 5 generates the gate signal, converted into a higher frequency or a lower frequency than the sound carrier wave to output an output signal (k) of the sound FM modulator. The output signal (j) of the image FM modulator and the output signal (k) of the sound FM modulator are synthesizidby a sinthesizer 6 and outputted as a high frequency signal (m). |
