| 摘要 |
PURPOSE:To use a specific channel as one dedicated to the reception of a weather forecast without replacing a quartz oscillator, by operating a local oscillating circuit as a fundamental wave oscillating circuit by using the quartz oscillator for the specific channel. CONSTITUTION:When clock pulse generator 1 is operated to select the 1st-5th channels, local oscillating circuit 4 operates as a side-overtone oscillating circuit as usual. To select the 6th channel for the exclusive use for the reception of a weather forecast, a switching transistor is turned on and capacitor C6 is connected in parallel to capacitor C4 of tuning circuit 5 to operate local oscillating circuit 4 as a fundamental wave oscillating circuit. In this case, quartz oscillator X1 dedicated to the 6th channel is previously fixed at a prescribed part, and inserting shortening plug 12 into one of receiving terminals 9, 10 and 11 of socket SO enables the invariable reception of radio waves from three weather forecast stations without replacing the quartz oscillator. |
