| 摘要 |
PURPOSE:To automatize a sound volume setting of a reproduced sound at every block unit by generating a sound volume instruction signal and supplying it to a sound volume adjusting means by a sound volume setting instruction corresponding to a sound data block. CONSTITUTION:The on/off of analog switches 23-26 is controlled by a sound volume instruction data in a control voltage generating circuit 22. That is, when the sound volume instruction data is, e.g., '00', only the analog switch 23 is turned on, when the sound volume instruction data is '01', only the analog switch 24 is turned on, when the sound volume instruction data is '10', only the analog switch 25 is turned on and when the sound volume instruction data is '11', only the analog switch 26 is turned on. Thus, a voltage introduced to a common connecting point of the analog switches 23-26 is a voltage in response to the sound volume instruction data and fed to an electronic volume 21 to control the resistance of the electronic volume 21. The sound volume is set by the voltage division of the reproducing audio signal by the electronic volume 21 and the resistor R1.
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