MX10C, MX40C Series of Optical Transmitters
Chapter 4: Operating Instructions
Page 16
TTN048898-D02
4.4
Laser Settings Page
To access the Laser Settings page, tap on the Laser monitors pane on the Home page. Here the user can control the
laser wavelength and choose whether or not to use the dither feature to stabilize the wavelength. Turning the dither off
will result in lower phase and intensity noise, but the wavelength may drift slightly over time. The monitors on this page
provide live readings of many parameters.
Caution
: The laser should not be turned on unless there is an optical fiber connected to the laser out port.
When the internal laser source is a C-Band or L-Band tunable laser, tap on the Laser Monitors pane on the Home page to access
the Laser Settings page. This page is not available when the 1310 nm fixed-wavelength source is the internal laser. When the
internal laser is not the standard C-band tunable laser, the laser type is denoted in the Options label on the rear panel of the
instrument (please see Figure 3 for location of the Options label).
Optical frequency can be set at increments of 50 GHz for C-band or L-band tunable internal lasers. C-band and L-band lasers
also support a fine tuning frequency offset feature, allowing the frequency to be adjusted by an offset from -30.000 GHz to
+30.000 GHz. The ITU channel number on these pages is an index number given only for convenience, which is unique to this
instrument; actual frequencies and spacings are specified by the ITU standard.
To adjust the ITU channel, tap on the ITU CHANNEL row and use the arrow buttons to increment or decrement the channel.
Press the green check mark to accept the new channel, or the red cancel button to abort the change. You may also use the
adjustment knob. Note that you are initially editing by channel, as indicated by the STEP CHAN button. Note that the frequency
and wavelength value are estimated based on the laser’s nominal 50 GHz channel spacing, not measured by the instrument.
Figure 24
Changing the ITU Channel Number
To apply a fine-tuning frequency offset, tap the STEP CHAN button. The button will cycle to the next mode, STEP 10GHz. In
this mode, using the up or down arrows or control knob will adjust the most significant digit of the frequency offset. Tapping the
button repeatedly will cycle through the STEP 1GHz, STEP 100MHz, STEP 10MHz, and STEP 1MHz modes, allowing you to
edit the offset in finer units of 1GHz, 100MHz, 10MHz, or 1MHz. Tapping the button one more time will cycle back to STEP
CHAN mode.
Tap here to change the laser
wavelength
Calculated frequency and
wavelength are displayed in
the monitor section.
Tap here to change the STEP size
