Agilent Technologies N5241A, Service Manual

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7-56 Service Guide N5242-90001
Repair and Replacement Procedures PNA Series Microwave Network Analyzers
Removing and Replacing the A54 Option 029 Test Port 2 Bridge and the A55 Option 029 Noise Downconverter N5241A/42A
Removing and Replacing the A54 Option 029 Test Port 2
Bridge and the A55 Option 029 Noise Downconverter
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 7-26 for this procedure.
CAUTION Be careful not to damage the center pins of the semirigid cables. Some flexing
of the cables is necessary, but do not over-bend the semirigid cables.
1. Disconnect the power cord.
2. Remove the outer cover. 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. Position the analyzer bottom side up.
5. The A54 test port 2 bridge, the A55 noise downconverter, and the cable connecting
these two assemblies, must be removed as a complete assembly.
6. Disconnect the ribbon cable (item
①
) from the A55 noise downconverter.
7. Disconnect the wire harness cables (item
②
), from the A55 noise downconverter.
8. Disconnect three semirigid cables (item
③
) and one flexible RF cable (item
④
) from the
A55 noise downconverter.
9. Disconnect two semirigid cables (item
⑤
) from the A54 test port 2 bridge.
10. Remove the hex nut (item
⑥
) and the screw (item
⑦
) that secure the A54 test port 2
bridge to the side frame.
11. Remove three screws (item
⑧
) that secure the A55 noise downconverter to the side
frame.
12. Move the disconnected cables out of the way and lift out the A54/A55 assembly.
13. Remove the assembly to be replaced.