| 摘要 |
A radio receiver capable of receiving world wide shortwave broadcasting programs is constructed of a phase-locked loop circuit, a standard time generating circuit, a memory, a timer unit, and a controller. The phase-locked loop circuit includes a frequency dividing circuit and performs a frequency conversion of a received signal by changing a frequency dividing ratio of the frequency dividing circuit. The standard time generating circuit counts the Greenwich standard time. A shortwave broadcasting service area is subdivided into a plurality of service ares based upon time difference data corresponding to the Greenwich standard time produced from the standard time generating unit. The memory stores therein a plurality of frequency data receivable within an area of the plural set areas. The timer unit counts local time obtained by correcting the Greenwich standard time derived from the standard time generating unit based on the time difference data from the memory. The controller selectively reads the frequency data from the memory based on the time difference data used when the local time is set to the timer unit, and then set the frequency dividing ratio of the phase-locked loop circuit based on the read frequency data. |
