| 摘要 |
<p>PURPOSE:To give a physically comfortable awakening, by varying stepwise the frequency of an alarm sound, and also setting the first sound to about 500Hz. CONSTITUTION:When an alarm switch 19 is closed at an alarm time, a frequency switching circuit 34 switches outputs D, E and F at every 64 seconds by an output of a 64-second counter 22. Subsequently, signals of 512Hz, 1,024Hz and 2,048Hz pass through AND gates 10-12 from a frequency dividing circuit 2 and are sounded successively from a loudspeaker 17 at every 64 seconds. When a snooze switch 26 is turned on, the frequency of an alarm sound is switched whenever it is turned on.</p> |
