Agilent Technologies HP 8719D Service Manual page 330

In addition to the analyzer, the system includes cables for interconnections, and
calibration standards for accuracy enhanced measurements.
Functional Groups of the Analyzer
The operation of the analyzer is most logically described in five functional
groups. Each group consists of several major assemblies, and performs a distinct
function in the instrument. Some assemblies are related to more than one
group, and in fact all the groups are to some extent interrelated and affect each
other's performance.
Power Supply.
The power supply functional group provides power for the
other assemblies in the instrument.
Digital Control.
The digital control group, which includes the front and rear
panels and the display, as well as the CPU, provides control to all assemblies in
the network analyzer. The graphics signal processor (GSP) provides an interface
between the CPU and the display.
Source. The
source group supplies a phase-locked and leveled microwave signal
to the device under test.
S-parameter test set, dividing the source signal into a reference path and a test
path, and providing connections to the device under test.
Receiver.
The receiver group measures and processes the input signals for
display.
The following pages describe the operation of the assemblies within each of the
functional groups.
The signal separation group performs the function of an
Theory of Operation