| 摘要 |
PROBLEM TO BE SOLVED: To solve the problem that image interference occurs at the time of VHF broadcast reception. SOLUTION: In a high frequency receiving apparatus having an UHF signal receiving unit 60 and a VHF signal receiving unit 61, the unit 61 is provided with tuning filters 62, 64, a mixer 65 having one output to which outputs of the tuning filters 62, 64 are connected and the other output to which a signal obtained by dividing an oscillation frequency of a local oscillator 56 is supplied, and a PLL circuit 78 connected to the local oscillator 56 in loop and having an output connected to the tuning filters 62, 64. The mixer is an image rejection mixer. By this configuration, since the configuration of the image rejection mixer is employed for a frequency band of VHF broadcast in which image interference likely occurs, even if the center of pass bands of the tuning filters 62, 64 does not completely match the frequency of a channel desired to be received for a tuning voltage from the PLL circuit 78, an image interference signal can be suppressed. COPYRIGHT: (C)2005,JPO&NCIPI
|
