| 摘要 |
PROBLEM TO BE SOLVED: To provide an FM stereo transmitter that employs only one crystal oscillator for the reduction of cost and prevents harmonics from a reference oscillator of a PLL from disturbing an FM broadcast band. SOLUTION: The FM stereo transmitter includes means 12, 15 each converting an L channel signal, an R channel signal, and a pilot signal into a stereo composite signal. A modulated wave obtained by frequency-modulating a carrier by a frequency modulation means 16, C4 to C6, R1 to R3, L1, D1 and D2 by using the stereo composite signal is transmitted. The transmitter is provided with an oscillator 2 for oscillating an oscillation frequency from which a frequency 38kHz is obtained by frequency division. The frequency modulation means 16, C4 to C6, R1 to R3, L1, and D1, D2 use PLL circuits 3 to 8 to control the frequency of the carrier by using the oscillation frequency. Whereas, the pilot signal is obtained by frequency-dividing the oscillation frequency. COPYRIGHT: (C)2006,JPO&NCIPI
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