The Tuning Field - Keysight N77 Series N7711A User Manual

The Tuning Field

Keysight N77xx Series
Switch the grid mode on or off
Select "Off" to switch to the tuning mode that is not affected by any
frequency grid. In this case all tuning controls that belong to the grid
tuning mode (see below) will be disabled and grayed-out. You can set
an arbitrary wavelength or frequency with a granularity of 100MHz.
Select "On" to switch to the grid tuning mode. In this case all tuning
controls that belong to the grid mode will be enabled also. In grid tuning
mode there is only a set of discrete grid frequencies possible to tune to
(see Set the frequency). The wavelength values are also limited to the
set of wavelengths that corresponds to the grid frequencies (see Set the
wavelength). The frequency grid is determined by the four grid tuning
parameters Reference Frequency at channel 0 (or f0), Channel Number
(or c), Channel Spacing (or s) and Fine Tune Frequency Offset (or
Deltaf). The grid frequencies can be calculated as follows:
The tuning mode can only be changed when laser output is "OFF".
Preset the frequency grid according to ITU (grid tuning mode only)
The grid tuning parameter will be set as follows:
•
Channel Spacing: 100 GHz
•
Reference Frequency at Channel 0: 193.1 THz
Grid mode off:
Tuning will not change your set value except clipping it to the supported
wavelength range.
Grid mode on:
Tuning will first clip your set value to the supported wavelength range.
After tuning the value will be changed to wavelength that corresponds
to the nearest frequency of the particularly set-up grid (see grid mode
parameters).
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Tunable Laser Source
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