EXFO FTB -5240S/5240BP Optical Spectrum Analyzer - Manual (Page 122)

Setting Up the Instrument in Drift Mode
116 FTB-5240S/S-P/BP
Setting Up Drift Analysis Parameters

Wavelength offset (nm): indicates the offset value applied on the
wavelength. This does not replace a calibration performed at
EXFO, but it can help you temporarily sharpen the specifications if
you have determined that, for example, your modules are used
beyond the normal allowed use. Entering a value in THz is not
possible. When an offset is applied, it is indicated at the bottom of
the graph (
).

Power offset (dB): indicates the offset value applied on the power.
This does not replace a calibration performed at EXFO, but it can
help you achieve the specifications if you have determined that, for
example, your modules are used beyond the normal allowed use.
When an offset is applied, it is indicated at the bottom of the graph
(P
).
To edit the power offset as a tap percentage, press the Edit %
button.
The percentage value entered in Edit percentage will be
converted to a corresponding equivalent value in dB.

Bandwidth at (dB): Set the power level used, relative to the
channel peak power, to compute the bandwidth.
5. Press OK to save the changes and close the window, or press Cancel to
exit without saving.
Press Restore Defaults to remove all the changes and apply the default
values.