Abstract: An ultrasonic nondestructive testing system of the pulse-echo type is disclosed including an echo-signal-translator exhibiting a bandwidth that is varied to achieve excellent near-surface resolution while affording deep inspection of an object under test.

Abstract: A distance amplitude compensation system is disclosed herein for comparing received signals with a reference signal having a time varying amplitude. The preferred embodiment of the invention disclosed herein is particularly adapted for use in an ultrasonic nondestructive testing system to vary the reference signal of the system as a function of time to compensate for variations of the echo signal produced by changes in the amplitude of the ultrasonic energy as it propagates through the workpiece as a result of attenuation or other causes. A pulser/receiver transmits ultrasonic signals into the workpiece, receives echo signals returned therefrom and produces received signals corresponding to the echo signals. A distance amplitude compensation generator produces a reference signal that has an amplitude that varies with time as a function of the manner in which the ultrasonic energy changtes as it propagates through the workpiece.