Anritsu BERTWave Series, Operation Manual, Page: 254 / 466

Chapter 6 How to Operate Sampling Scope
6-60
6.3.2 Adjusting Dark Current
When light is not input to the Optical connector, the O/E module output
voltage is adjusted.
The output voltage of the O/E module used changes depending on the
ambient temperature.
Calibrate the MP2110A before using the optical connector.
1. Confirm that no light has been input to the optical connector (SMF or
MMF).
2. Click Amplitude.
3. Click the O/E tab.
4. Click Calibrate Module.
5. The window confirming that the light is not input is displayed. Click
OK.
6. In about 5 seconds from step 3, the dialog box appears indicating that
the calibration is complete. Click OK.
6.3.3 Adjusting values for changing the wavelength bands
To measure an optical signal at the other wavelength band than 850 nm,
1310 nm or 1550 nm, adjust the values of Conversion Gain and
Responsivity.
Warm up the O/E module at least one hour because the output voltage
varies depending on the ambient temperature. Additionally, be sure to
calibrate the sampling oscilloscope before performing adjustment.
<Adjusting Manually>
Adjustment method of Conversion Gain
1. Adjust the wavelength of the optical power meter to the optical
signal.
2. Measure unmodulated optical signal power with the optical power
meter.
3. Input the optical signal to the optical input connector.
4. Measure the average of the optical signal power by using the
Histogram function of the sampling oscilloscope.
5. Click Amplitude.
6. Click the O/E tab.
7. Select User for the connector of the optical signal input at Input
Connector (Wavelength).
8. Adjust the Conversion Gain value so that the average of the optical
signal power measured by the Histogram function of the sampling
oscilloscope becomes equal to the value measured by the power meter.