DMQ QSV-B, Руководство пользователя

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should always seek expert advice or refer to specific textbooks on
measuring the sound velocity of materials using an ultrasonic velocity
gauge. Additional information can also be found on the internet and
through local government agencies as well as in technical institutes.
The QSV operates with dual crystal transducers that use the “pitch-
catch” principal. Dual crystal transducers use two piezoelectric crystals
whereby one crystal is excited with short electrical pulses from the unit
sending short acoustic waves into the test piece. The second crystal
then receives the acoustic waves reflected at the end of the test piece.
The frequency of the acoustic waves changes between 2 and 10 MHz
depending on the probe being used.
Figure 1: Transducer signals (acoustic wave representation)