Digitizing and representation of an A-scan using a graphic display leads to a distortion of the echo shape in comparison to an A-scan on an analogue display (CRT). In addition the A-scan refresh rate is limited by the used screen technology. New techniques of digitization including interpolation methods, of signal processing, as well as a new way of displaying the signals on a digital screen (Smart View or EchoMax) in modern Ultrasonic Flaw Detectors are presented, with the aim of reaching the display quality of an analogue screen. The operator shall get the feeling of using an analogue instrument without missing the advantages of the modern digital technology. Still today, analogue instruments show sometimes a better performance on the screen compared to digital instruments, especially with high speed scanning, large dimensions of the test objects and subsequent high gain settings. With the critical applications like forging and casting inspection, the new instrument technology was tested. The results in comparison with the analogue technique will be discussed.
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