Checkline TI-MVX - Manual (Page 37)

CHAPTER SEVEN: USING THE A-SCAN & B-SCAN DISPLAYS
A key feature of the TI-MVX is the waveform display. The waveform is a graphical
representation of the sound reflections returning to the transducer. Consider
standing at the base of a canyon and screaming “Hello There”. After a brief
delay, you will here multiple echoes, “Hello There’s” repeated back to you. The
waveform display shows the amplitude of the signal received on the vertical (Y)
axis and time (shown in units of thickness) on the horizontal (X) axis.
The waveform display is very useful for viewing and adjusting the location of the
gates. The gates are typically used to eliminate potential surface noise by adjust-
ing the starting point in single echo modes, for multi echo measurement modes,
as well as to adjust the threshold (sensitivity) in either mode. The waveform dis-
play is also very useful for locating pits and internal flaws in materials.
The B-Scan display is also very useful when scanning surfaces and viewing the
cross section of the test material. It provides a convenient way of profiling the
blind surfaces during a scan. The B-Scan display is also equipped with a scan
bar representing the overall thickness. The scan bar gives the user a visual indi-
cation when a flaw or defect passed over during the scan process. The scan bar
will deflect off of the defect and return back to the overall thickness. Visually, this
is much easier to notice than watching for changes in the digital value displayed.
The scan bar has also been included in the large digits display mode for the
same purpose.
Note: The following chapter outlines some of the fine adjustment features of
the TI-MVX. The TI-MVX has four different display options (RF A-Scan, Rectified
A-Scan, B-Scan, and Large Digits). We’ll take a better look at these options in
this chapter. Note: In order to recall and use the new adjustments made to the
TI-MVX at a later time, the user must save the modified settings in one of the
setup locations prior to powering off the unit. Refer page 74 for more information
on setups.
7.1 Selecting a Display Option
The following procedure outlines how to select or toggle display options:
Changing Display Options
1) Press the MENU key once to activate the
menu items tab. Press the MENU key multiple
times to tab right, and the ESC key multiple
times to tab left, until the DISP menu is high-
lighted and displaying the submenu items.
2) Use the UP and DOWN arrow keys to scroll through the sub menu items until
VIEW is highlighted.
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H) Hot Menus -Each of the fields located under the display are called the Hot
Menu Fields. These fields allow quick control of some of the fine adjustments
needed to control the display settings, measurement modes, and grid memory
control. All of these fields can be adjusted without having to activate the tabbed
menu items and searching through a variety of menus to make adjustments.
7.3 Adjusting the screen
The width refers to the overall viewable range, with respect to depth, being dis-
played on the screen. The starting depth is displayed at the lower left side of the
screen, and the ending depth is shown at the lower right hand side of the
screen. The difference between these values is called the Width. The procedures
to adjust the Width are outlined below:
Adjusting the Width using the Hot Menus
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 WIDTH cell is highlighted.
2) Press the UP, DOWN, LEFT, and RIGHT arrow
keys to scroll the highlighted value.
3) Alternatively, press the ENTER key to display
the Digits Edit Box.
4) Press the UP and DOWN arrow keys to scroll
the highlighted value.
5) Press the LEFT and RIGHT arrow keys to
scroll the digit locations.
6) Repeat steps 4 & 5 until the WIDTH value is correctly displayed.
7) Press the OK key to return to the measurement screen, or ESC to cancel
entering the WIDTH.
The user can also access and adjust the width from the tabbed menus. However,
this method is a more tedious than making the adjustments using the Hot
Menus. The procedure using the tabbed menus is outlined below:
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