EXFO FTB -5240S/5240BP Optical Spectrum Analyzer - Manual (Page 237)

Setting Up the Instrument in EDFA Mode
OSA 231
Setting Up EDFA Analysis Parameters
5. Modify the settings as needed. For more information about the settings,
see Managing Channels on page 224. If you leave a box empty, it will
remain as it was before your changes.
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.