Checking The Source Group - Agilent Technologies E8362A Service Manual

Troubleshooting
Measurement System Troubleshooting

Checking the Source Group

Serial Bus Test
Before performing tests on specific assemblies in the source group, it is recommended that
you perform the serial bus test. This may help to isolate the failure to a specific assembly.
Through the front panel, the serial bus test allows you to check signal and voltage levels at
32 points (nodes) distributed across four of the printed circuit board assemblies in the
analyzer. With this test you can isolate problem board assemblies in the analyzer. The
board assemblies tested and their associated node numbers are as follows:
NOTE This test is written for a PNA series network analyzer as it was originally
shipped from the factory. Due to changes in board production, this test may
not show accurate pass/fail results if the A8, A10, A11, A12, or A16 board has
been replaced with a newer board assembly.
Board Assembly
A12 source 20
A10 frequency reference
A11 phase lock
A8 fractional-N synthesizer
A16 test set motherboard, MA 20
A16 test set motherboard, SOMA 50
A16 test set motherboard, AUX 1
A16 test set motherboard, AUX 2
Descriptions of each board assembly and nodes are included in this section. Location of the
nodes is indicated with a ♦ symbol on the block diagrams located at the end of this chapter.
Performing the Serial Bus Test
First, this test sequentially checks all 48 nodes at 45 MHz. Next, the test checks all nodes
that change values with frequency, at 49 different frequency points. For each node,
measured values are copied to an ASCII text file in the service directory on the hard disk
drive. Any measured values that exceed the tolerances are highlighted in the application
and the data file.
To run the serial bus test:
• On the System menu, point to Service, and then click Serial Bus Test.
• The dialog box in
4-32
Figure 4-10 on page 4-33
PNA Series Microwave Network Analyzers
Node Numbers
111 to 118
211 to 218
311 to 318
411 to 418
511 to 518
611 to 618
711 to 718
811 to 818
is displayed. Click Begin to start the test.
Service Guide E8364-90001
E8362A, E8363A, E8364A