| 摘要 |
PURPOSE:To remove the same channel beat generated by the dislocation of the frequency of the reproducing carrier and the carrier of an ON air wave by synchronizing a carrier for TV modulation with the carrier of an ON air wave for an area for a channel reproduction in a sub-band transmission and light transmission. CONSTITUTION:With a PLL, a carrier for channel reproduction is created, an ON air wave is put into the PLL, a local signal oscillated from a voltage controlled oscillator VCO is synchronized with the carrier of the ON air wave and the synchronized signal is put into a TV modulator 4 as a reproducing carrier. The video signal and the sound signal are modulated to UHF or VHF. At this time, since the reproducing carrier and the carrier of the ON air wave are synchronized, the same channel beat does not occur.
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