Using the Optical Spectrum Analyzer

The Amplitude Menus

Note

The optical spectrum analyzer performs a more complete zeroing when the instrument is first turned on. You can run this more complete routine anytime by pressing the Zero Now softkey. Refer to “To zero the instrument” on page 3-50for more information.

Auto Chop Mode

Enables the spectrum analyzer chop mode. Chop mode increases dynamic range for long sweep times by subtracting ambient light. Subtracting the ambient light can improve sensitivity but slow down the sweep speed.

Pressing the front-panel Preset key turns this function OFF.

Note

Sweep times of 50 msec × the # of trace points, or longer, use a special “chop” mode. Chop mode increases dynamic range, stabilizes measurements against drift, and reduces effects of stray light. This special chop mode is enabled by setting the Auto Chop mode to ON.

Power Calibration

Power Calibration allows you to use amplitude correction factors either from the factory calibration or from the last successful user calibration. Pressing the front-panel Preset key resets this function to User. If a user calibration has not been performed, the factory calibration data is used.

User Power Cal Date

The User Power Cal Date displays the date of the last successful user-performed amplitude calibration. See “To perform a power calibration” on page 3-44for information on performing an amplitude calibration.

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