| 摘要 |
PROBLEM TO BE SOLVED: To reduce the size and cost of a composite PLL tuner, and at the same time, to constitute such a tuner unit that the influence at the time of inputting BUS data can be reduced. SOLUTION: A composite PLL tuner unit is composed of a modulator section 3, which mixes one-side high-frequency signals distributed from a signal distributing circuit 2 connected to an antenna input terminal 1 with video signals and audio signals inputted from the outside and outputs the mixed signals through a television output terminal 6, a tuner section 4 which fetches the signal of a receiving channel from the other-side high-frequency signals distributed from the distributing circuit 2, amplifies, and converts the amplified signals into intermediate-frequency signals, and one PLL circuit 8 which controls the oscillation frequencies of a local oscillation circuit 37 of each modulator section 3 and the local oscillation circuits 44 and 54 respectively of the blocks for UHF and VHF bands of the tuner section 4. The circuit sections are arranged on the same substrate, and at the same time, the antenna input terminal 1 and the television output terminal 6 are arranged in the same end section of the substrate.
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