EXFO FTB -5240S/5240BP Optical Spectrum Analyzer for FTB 500 (NS-1434) - Manual (Page 338)

Managing Results
330 FTB-5240S/5240BP
Managing Drift Test Results
Markers Tab
You can use markers to perform manual measurements and verification
directly on the trace. There are two vertical and two horizontal markers
indicating the wavelength and power positions respectively, which you can
also move directly on the trace using the zoom select option. You can
measure actual power and wavelength values of any point on the trace.
Note: These markers are visible in the WDM Graph tab only when the markers
tab is selected in the main window.
Note: Horizontal markers will be displayed only if the markers are activated in
the Preferences tab.
When the vertical markers are set, you will find two markers identified by
the letters A and B in the WDM Graph tab. Horizontal markers are
identified by letters C and D. These markers are represented both in the
graph and the markers tab to customize your markers.
The application allows you to fix the distance between the vertical
markers. When this feature is activated, while moving any one marker,
both markers shall move at the same rate and distance.
The markers A and B in the Markers tab act as toggle buttons to enable
selection. When a marker is activated, the colour of the button changes to
orange and the selected marker displays a double arrow at the base of the
marker in the WDM Graph tab, which means that the marker can be
moved.
At this point, if you press the other vertical marker in the WDM Graph tab,
the selection of the toggle switches to this marker. However, if you select
the other marker button from the Markers tab, both the markers will be
selected and the distance between both will be locked. When both the
vertical markers are locked for fixed movement, pressing any horizontal
marker from the Markers tab or the WDM Graph tab will remove the
selection of both the vertical markers.