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Application Tutorials
Tutorial 3: Measure Extinction Ratios on Low-Level Signals
Autoscaled Display of Low-Level Signal
4Turn filtering on by pressing:
Setup, eyefltr ON OFF ON
Perform an Offset Calibration
This calibration procedure removes any offset that may be present in the opti-
cal-to-electrical converter. This is sometimes referred to as the "dark" level.
The offset calibration ensures accurate measurements of the laser’s level.
5Turn the laser off. (If you are measuring the pattern generator directly ,
disconnect the input signal at channel 1.)
6Perform the calibration by pressing:
Trg,Cal, OFFSET CAL, CONT
The calibration takes about a minute to execute. When the calib ra t ion is
finished, DC NULL: done is displayed.
7Turn the laser on. (If you are measuring the pattern generator directly ,
reconnect the input signal at channel 1.)