| 摘要 |
PURPOSE:To set the display part to a low luminance automatically at a sleep time, by setting the display part to a low luminance independently of its luminance set state when the sleep operation overlaps during setting of an alarm. CONSTITUTION:A switch S3 is provided to switch the luminance of a display part 2 to a high value or a low value, and the output voltage of a transformer T is supplied to the display tube of the display part 2 through a clock part 1. When a switch S5 for the sleep operation and a switch S1 for setting an alarm are turned on together, an FF4 is set by the output of an AND circuit 3 to turn off a transistor TR Tr1 and turn on a TR Tr3. Independently of the set state of the switch S3, the output voltage of a middle terminal of the transformer T is supplied to the display part 2 to set the display part 2 to a low luminance. When the alarm operation is started or power is supplied to a radio part by an external switch S4, the FF4 is reset, and the luminance of the display part 2 is set to a luminance set by the switch S3. |
