The error could be caused by one of the following:
- The calibration output connector may be dirty or damaged causing a decrease in power. Use the fiber connector inspection scope to check the end face of the calibration output connector on the OSA.
- Wrong type, dirty or defective test fiber could be causing excessive loss (i.e. reduced power)
- The internal gas cell may have an issue (very rare), thus the Calibration Notch is not being detected.
Suggested settings to see the 1530.3714nm cal point;
CENTER = 1530nm
SPAN = 3.0nm (1528 to 1531 nm)
LOG SCALE = 1.0dB/Div (or lower)
AUTO REF LEVEL = ON
RESOLUTION = 0.02nm (or 0.05nm is okay, too)
SENSITIVITY = MID (or higher)
Training Module Procedure:
One way to verify the Fiber health and Cal signal is to follow the exercise in the OSA training module to adjust the settings to manually verify the Cal Notch at 1520.3714nm.