Anritsu BERTWave MP2100B, Operation Manual, Page: 274 / 382

Chapter 8 Operating Optical Interface
8-12
8.3.2 Calibrating O/E module
When light is not input to the O/E module, the output voltage is adjusted.
The output voltage of the O/E module changes depending on the ambient
temperature.
Calibrate the BERTWave before using the O/E module.
1. Screw in the O/E Data In cap.
2. Touch
[Calibrate Module].
3. The window confirming that the light is not input is displayed. Touch
[OK].
4. In about 5 seconds from step 3, the dialog box appears indicating that
the calibration is complete. Touch [OK].
8.3.3 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, Responsivity,
and System Conversion Gain.
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 (System 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. Display the O/E setting panel.
6. Set Wavelength to User.
7. 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.
The System Conversion Gain value is automatically set by setting
the Conversion Gain value.