Preparatory Notes for ASNT NDT Level III Examination - Ultrasonic Testing, UT

Instrumentation Filtered Band Width:
1. Broad band instrument means a wide array of frequencies could be
processed by the instrument. The frequencies shown will be a close
representation of the actual electrical signal measured by the receiver
transducer. The S/N may not be very good, the shape of the amplitude
tend to be the actual representation.
2. Narrow band instrument, suppressed a portion of frequencies above and
below the center frequency. With the high frequencies noise suppressed,
gain could be increase, leading to improved sensitivity. However the shape
and relative amplitude of pulse frequency components often altered