Agilent Technologies N5242A, Service Manual

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7-18 Service Guide N5242-90001
Repair and Replacement Procedures PNA Series Microwave Network Analyzers
Removing and Replacing the A15 Midplane Board N5242A
Removing and Replacing the A15 Midplane Board
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 7-8 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 A16 power supply assembly. Refer to “Removing and Replacing the A16
Power Supply Assembly” on page 7-20 .
4. Remove the A17 CPU board assembly. Refer to “Removing and Replacing the A17 CPU
Board Assembly” on page 7-22 .
5. Remove six screws (item
①
) from the A15 midplane board.
6. Lift the board ejectors (item
②
) to the upright position to disengage the A15 midplane
board from the A14 system motherboard.
7. Note the positions of the five rubber grommets (item
③
) on the bottom three A15
midplane board alignment pins. Remove these rubber grommets and retain them for
reinstallation on the new A15 midplane board.
8. Lift the A15 midplane board out of the analyzer.
Replacement Procedure
1. Reverse the order of the removal procedure.
Be careful to align the guide pins on the A15 midplane board connectors with the slots
on the A14 system motherboard connectors.
The board ejectors should be in the upright position when installing the A15 midplane
board. Align these ejectors with the slots in the chassis inner panels as the board is
lowered into position and then push them down flat.
Remember to install the five rubber grommets on the bottom three alignment pins: one
on the alignment pin closest to the fans and two each on the other two alignment pins.
2. Perform the post-repair adjustments, verifications, and performance tests that pertain
to this removal procedure. Refer to Table 7-2 on page 7-64 .