| 摘要 |
PURPOSE:To keep the clip level constant regardless of the variance of temperature by reducing the supply voltage of an amplifying circuit when the temperature is raised in response to the input of a temperature detecting element. CONSTITUTION:A low frequency modulated signal of sounds or the like is led out to a line 3 from a line 1 through an amplifying circuit 2, and the amplifying circuit 2 is energized by the power from a power supply circuit 4. The power supply circuit 4 reduces the supply voltage to the amplifying circuit 2 if the temperature is raised in response to the output from a temperature detecting element 5. Consequently, the supply voltage to the amplifying circuit is reduced in response to the output of the temperature detecting element to suppress the rise of the clip level if the clip level of the amplifying circuit is apt to rise in accordance with the variance of temperature. Thus, the clip level is kept at a preliminarily determined certain value regardless of the variance of temperature. |
