| 摘要 |
<p>PURPOSE:To stop a sound time signal automatically at night, etc. so as not to interrupt sleeping, etc., by giving a sound time tone only when brightness exceeding a prescribed value is detected by the illumination intensity sensor. CONSTITUTION:An output of the quartz oscillator 2 is divided by the frequency dividing circuit 3, is counted by the time counter 5, and a time signal (k) and a just o'clock signal (b) are obtained. The signal (b) between them is provided to the controller 8. On the other hand, the illumination intensity sensor 13 detects the brightness of the inside of the room or the outside of the room, and in case when its brightness exceeds a reference value, a time tone request signal is provided to the controller from the illumination intensity deciding circuit 14. When the time tone request signal has been provided, the controller 8 outputs a ready signal C to the synthesizer 10, by which a time tone by sound is given from the speaker 12. On the contrary, when the time tone request signal is not output, a time tone is not sounded even if the signal (b) is inputted to the controller 8.</p> |
