Agilent Technologies 86038A User Manual page 94

Function Reference System Menu
Real-Time Port Monitor
Displays on a horizontally scrolling graph the real-time gain/loss and
group delay measurements enabled for Port 1 and Port 2. The monitor
operates in repeat sweep mode at the center wavelength of the
measurement range and uses a 2 GHz Mod Frequency and 30 Hz IF
Bandwidth.
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 group delay
values approaching or below 50 fs. When a frequency selective test device
is in the measurement path, the center wavelength should be set using
Setup > Meas Range start and stop settings to a center wavelength that
provides a low insertion loss point.
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.
For less demanding applications, such as ±250 fs of RGD accuracy, usual
good practice in making optical connections provides adequate results
without using the Real-Time Port Monitor.
resets the measurements and clears the graph data.
Clear Plots
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Agilent 86038A Optical Dispersion Analyzer, Third Edition