Real-Time Port Monitor - Agilent Technologies 86038B User Manual

internal monitor power is too low. These warnings either
indicate a need for optimization of the modulator bias or input
polarization, a problem in the optical connection to the tunable
laser, or an internal optical problem. Please refer to the
Troubleshooting chapter for further information.
Automatic Canceling
If TLS wavelength instability is detected in a sweep, and a
repetition of the sweep is again instable, the measurement is
canceled and a message appears in the log. In this case, it may
be necessary to reduce the sweep range for the measurement.
Deactivating this function allows the measurement to complete,
but care should be taken in using the results.

Real-Time Port Monitor

Displays on a horizontally scrolling graph the real-time
gain/loss and group delay measurements at the DUT Port
receiver and monitor receiver. The Port Monitor operates in
repeat sweep trigger mode at fixed wavelength and uses a 2 GHz
modulation frequency and 30 Hz IF bandwidth. The wavelength
can be set in the wavelength text box, generally to the center of
the measurement wavelength range, or to the pass-band in the
case of a wavelength-filtering DUT.
The real-time monitor can be used to check the stability of the
test system, test device, and interconnecting cables before
performing an actual measurement. This is especially useful
when measuring small relative group delay values approaching
or below 50 fs and for long-fiber measurements, for which
temperature instability causes substantial GD variation. After
using the Real-Time Port Monitor to verify that the DUT
connections are good and test environment is stable, the setup
is ready for a measurement. The stability of the setup could
appear different for the DUT than for the normalization due to
actual temperature changes, longer fiber lengths, insertion loss,
mechanical movements, air currents, and so on.
Clear Plots resets the measurements and clears the graph data.
Port buttons allow selecting the Port configuration if an
integrated switch is installed.
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Agilent 86038B Photonic Dispersion and Loss Analyzer, Second Edition