HP 8753E - A Close Look at the Analyzers Functional Groups

A Close Look at the Analyzer’s Functional Groups
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 consists of the A8 post
regulator and the Al5 preregulator. It supplies power to the other assemblies
in the instrument.
Digital Control. The digital control group consists of the Al front panel and
A2 front panel processor, the A9 CPU, the Al6 rear panel, the Al8 display
and the A19 graphics system processor (GSP). The A10 digital IF assembly is
also related to this group. These assemblies combine to provide digital control
for the analyzer.
Source. The source group consists of the A3 source, A7 pulse generator, All
phase lock, Al2 reference, Al3 fractional-N (analog), and Al4 fractional-N
(digital) assemblies. The A4 sampler is also related since it is part of the
source phase lock loop. The source supplies a phase-locked RF signal to the
device under test.
Signal Separation. The signal separation group performs the function of an
S-parameter test set, dividing the source signal into a reference path and a
test path, and providing connections to the device under test. It consists of
the A24 transfer switch, the A21 test port 1 coupler, and the A22 test port 2
coupler.
Receiver. The receiver group consists of the A4/A5/A6 sampler/mixers and
the A10 digital IF. The Al2 reference assembly and the A9 CPU are also
related. The receiver measures and processes input signals for display.
The following pages describe the operation of each of the functional groups.
124 Theory of Operation