| 摘要 |
PURPOSE:To facilitate the setting of a recording level by designing the titled device so that a digital signal is read by the interlace scanning of a disc and a mean level corresponding nearly to the mean value of the analog output of an entire sampling scanning period or the mean level of each sample is decided based on the reading. CONSTITUTION:A signal read by the sampling scanning is converted into an analog signal and inputted to an integrater 20. The integrater 20 integrates each sampling and outputs a mean level. The mean level is held in a hold circuit 21. The mean level obtained from the hold circuit 21 becomes an input to a comparator circuit 23 through a resistor 17 and is compared with a reference voltage (optimum recording level). A motor 17b moves a slider 17a and when both inputs to the comparator circuit 23 are equal, an output is zero volt, the motor 17b is stopped and the attenuation by the resistor 17 is fixed. Thus, the setting of the optimum recording level to the mean level of the reproduced output of a CD 1 is completed.
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