Agilent Technologies N5241A, Service Manual

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7-16 Service Guide N5242-90001
Repair and Replacement Procedures PNA Series Microwave Network Analyzers
Removing and Replacing the A14 System Motherboard N5241A/42A
Removing and Replacing the A14 System Motherboard
Tools Required
• T-10 TORX driver (set to 9 in-lb)
• T-20 TORX driver (set to 21 in-lb)
• 5/16 inch open-end torque wrench (set to 10 in-lb)
• ESD grounding wrist strap
Removal Procedure
Refer to Figure 7-7 for this procedure.
1. Disconnect the power cord.
2. Remove the outer and inner covers. Refer to “Removing the Covers” on page 7-6 .
3. Remove the front panel assembly. Refer to “Removing and Replacing the Front Panel
Assembly” on page 7-8 .
4. Remove the A18 GPIB board. Refer to “Removing and Replacing the A18 GPIB Board”
on page 7-24 .
5. Remove the A15 midplane board. Refer to “Removing and Replacing the A15 Midplane
Board” on page 7-18 .
6. Remove the A4–A13 boards. Refer to “Removing and Replacing the A4–A13 Boards” on
page 7-14 .
7. Remove the fan bracket and fans. Refer to “Removing and Replacing the Fans” on page
7-62 .
8. Turn the analyzer over so that the bottom side is up and remove four screws (item
①
),
that secure the bottom of the midplane bracket to the chassis.
9. Turn the analyzer back over so that the top side is up. Remove seven screws (item
②
)
that secure the left side bracket to the chassis left inner panel.
10. Remove two screws (item
③
) from each side that secure the midplane bracket to the
chassis left and right inner panels. Lift the midplane bracket out of the analyzer.
11. Remove three screws (item
④
) that secure the A14 system motherboard to the chassis.
12. Slide the A14 system motherboard toward the rear of the analyzer to release it from
the 15 keyhole standoffs (item
⑤
) on the chassis.
13. Lift the A14 system motherboard just enough to unplug the ribbon cable from the
bottom side, then lift it out of the analyzer.
Replacement Procedure
1. Reverse the order of the removal procedure.
2. Perform the post-repair adjustments, verifications, and performance tests that pertain
to this removal procedure. Refer to Table 7-2 on page 7-68 .