| 摘要 |
PURPOSE:To simply discriminate a fact that the sounds are properly absorbed by checking the display state of a display device provided on a microphone device in accordance with the detection level of a detector device. CONSTITUTION:The input signal rectified by a rectifier diode 13 is supplied to a level discriminator circuit 19 via a variable resistor 15. At the same time, the output of the resistor 15 is divided by a series circuit of resistors 16, 17 and 18. Then the signalsreceived from the joint between resistors 16 and 17 and the joint between resistors 17 and 18 are supplied to the circuit 19. The circuit 19 consisting of a microcomputer discriminates the levels of the signal received from the resistor 15 and two types of divided signals based on the output received from microunits 11, 2a1 and 2b. When these discriminated levels are higher than each set threshold level, the control signal is supplied to a display panel 30 via a drive circuit 20. Thus the panel 30 consisting of a liquid crystal display shows those level states in a bar graph using three bars. |
