DFX-7
Ultrasonic Flaw Detector
27
4.3 Gain
The gain feature of the
DFX-7
is used to adjust the signal amplitude to a
predetermined reference height for the inspection process. The higher the gain the
more the sound is amplified. The gain, or amplification of the return echoes, can be
adjusted in the
DFX-7
to accommodate a variety of applications. The setting of the
gain is crucial in order to obtain valid readings during the inspection process.
Too much gain may result in erroneous measurements, by detecting on noise rather
than the actual reflector or defect. Not enough gain may result in intermittent
detection. It may also result in lack of detection on internal flaws, pits, or porosity.
The gain can easily be compared to the volume control of a home stereo system. If
you turn it up too much, you can’t hear the music clearly. If it’s turned down too
much, you can’t hear it at all. The
DFX-7
commands a 110dB gain range using 3
stages of amplification. The overall range makes the DFX-7 extremely versatile
regarding a variety of applications and material types.
The procedures to adjust the
Gain
are outlined below:
Adjusting Gain
1) Press the
MEAS
key once to activate measure menu items. Press the
MEAS
key multiple times to move right, and the
ESC
key multiple times to
move left until the
GAIN
cell is highlighted.
