Tektronix OM4006D, Руководство пользователя

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Appendix C: Calibration and adjustment (RT oscilloscope)
Hybrid calibration (RT)
This is a factory calibration. Imperfections in the OM4000 instrument receiver
are corrected using a factory-supplied calibration table. Check the Setup tab for a
green indicator to be sure the OUI is successfully retrieving the Reference laser
(Local Oscillator) frequency and power which are needed to choose the correction
factors from the calibration table. The table is the pHybCalib.mat
fi le in the
ExecFiles directory. You can verify you have a valid pHybCalib fi le by connecting
to an oscilloscope, typing pHybInUse in the MATLAB Engine Window, and
clicking Single. Similarly, EqFiltInUse shows the equalization
fi lter in use (if any).
The information statement contains the serial number, date of calibration, and
other notes about the calibration. If the serial number is correct then you have
the proper
fi le.
The following procedure can be used to verify and correct the calibration at a
single wavelength using a minimum of external hardware. This procedure assumes
that “Laser 1” and Laser 2” can be tuned to the same wavelength. It is easiest if
you have a polarization controller before the signal input, but the instructions are
written assuming you are moving the
fi ber around to change the input polarization.
Hybrid calibration
prerequisites (RT)
System should be deskewed following the procedure above.
Connect the Reference as usual from Laser 2 to the Reference input with
short PM/APC jumper.
Use a standard SM/APC (not PM) fi ber to connect the Laser 1 to the Signal
input. Use the LRCP to set the Signal 1 power level to about 10 dBm to start.
In the LRCP tool:
Turn on both lasers and tune them to the same channel where you will
be working.
Set the Laser 1 power to get about 100 mV pp.
Tune Laser 1 off grid by 100 to 500 MHz
OM4000D Series Coherent Lightwave Signal Analyzer 115