| 摘要 |
PURPOSE:To utilize an acoustic equipment, such as a radio receiver, as an alarm clock by generating a sound, whose volume has been set, when a timer time has expired after a sound whose volume is varied by a timer switch means is generated. CONSTITUTION:A sound received by a radio receiver, etc., is sent from speaker 9 via variable volume VR1 with small volume and at the time set by timer 1, switch S1 is opened to turn off power circuit 10, so that the generation of the sound will stop before sleeping. At an alarm time, timer 1 closes switch S1 and FF4 is inverted into the set state through set-reset signal generating circuit 3 of control circuit 2 to turn on transistor Q. Consequently, switch S2 of change-over selecting circuit 5 is changed over via relay 6 to generate a radio reception sound of volume detected by volume setting volume VR2 as an alarm sound, so that an acoustic equipment such as a radio receiver can be utilized as an alarm clock effectively. |
