| 摘要 |
The invention relates to a volume control circuit for radio alarms, constructed from resistors (r1 to r9), bipolar transistors (t1 to t7), a capacitor (c) and an insulation-layer field-effect transistor (i), which makes it possible to control the volume of a radio alarm in such a manner that, during the sleeping switch-off phase, said volume is gradually reduced after a specific time to complete silence, and gradually rises in the alarm phase, a final level finally being reached which is higher than in the sleeping switch-off phase. <IMAGE>
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