ULTRASONIC FLAW DETECTOR

摘要

PURPOSE:To improve measuring operability sharply and to attain more precise measurement by automating the attenuation ratio setting operation of an attenuator to include a decibel value processed by the attenuator always within a highly accurate reading range without manual operation. CONSTITUTION:The arithmetic processing of e=20log c/d is executed on the basis of an output value (c) obtained by A/D converting an analog signal attenuated by the attenuator 6 and a reference value (d) obtained from a reference value oscillation circuit 8 to obtain an attenuation decibel value (e). The calculated attenuation decibel level (e) is compared with a set-up attenuation decibel value (f) obtained from a set-up attenuation decibel value oscillation circuit 10 by a comparator 11. The attenuation ratio of the attenuator 6 is automatically set up and changed by a setting/changing means 12 on the basis of said compared result so that the calculated attenuation decibel value (e) is '0' or less and the set-up decibel value (f) or more, i.e. the value (e) is included within the highly accurate reading range.