EXFO FTB-5230S Optical Spectrum Analyzer for FTB 200 v2 - Manual (Page 137)

Setting Up the Instrument in Drift Mode
OSA/OCA 131
Setting Up Drift Analysis Parameters
5. Modify the settings as needed. For more information about the settings,
see Managing Channels on page 124. If you leave a box empty, it will
remain as it was before your changes. Modify appropriate settings.
6. Press OK to return to the Channels tab, which now contains the
modified settings.
7. Press OK to save the changes and close the window, or press Cancel to
exit without saving.