| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a variable condenser capable of reducing cost by simplifying a receiving circuit, without scarifying the operability of a tuning operation in an FM band. SOLUTION: A resonance circuit 12 for oscillation is constituted of a variable condenser 1202 and a coil 1204 connected in parallel, and the resonance frequency of the resonance circuit 12 for reception is decided, according to the capacitance value of the variable condenser 1202 and the inductance value of the coil 1204. A resonance circuit 14 for RF amplification is constituted of a variable condenser 1402 and a coil 1404 connected in parallel, and the resonance frequency of the resonance circuit 12 for oscillation is decided, according to the capacitance value of the variable condenser 1402 and the inductance value of the coil 1404. If the whole range of the angle of rotation of a rotor is defined as R0, and the range of the angle of rotation of the rotor corresponding to the range of the capacitance value necessary for the tuning of an FM band is defined as R1, the respective variable condensers 1202 and 1402 are constituted, so that the value of the R1/R0 satisfies being not less than 1/2 and not more than 2/3.</p> |
