| 摘要 |
PURPOSE:To avoid the mishearing of an alarm announcement and the disturbance of the alarm sound at night, by varying the alarm sound volume at a fixed time in accordance with the ambient brightness and at the same time giving a difference between the alarm sound volume and that at the set time. CONSTITUTION:A CPU processes the signals of various keys which are fed via an interface I/F and decides the state of the ambient brightness based on the signal fed from an optical sensor part X. Then the timing information, etc. is displayed at a display part DISP, and the timing information is supplied to a voice synthesizer VS to deliver the time in voice every hour on the hour. The output of the synthesizer VS is delivered in the form of a voice through a speaker SP via a D/A converter, a resistance R1 and an emitter follower transistor (TR) 2 respectively. In case the signal A1 of a high level is applied to the base of a TR 1 from the CPU, the sound volume is reduced. While the sound volume increases when the signal A1 of a low level is applied. |
