Removing And Replacing The A38-A41 Source Attenuators And The A46-A49 Receiver Attenuators - Keysight N5227A Service Manual

Repair and Replacement Procedures
Removing and Replacing the A38–A41 Source Attenuators and the A46–A49 Receiver Attenuators
Removing and Replacing the A38–A41 Source Attenuators and the A46–A49
Receiver Attenuators
Tools Required
• T-10 TORX driver (torque to 9 in-lb or 1.02 N.m)
• T-20 TORX driver (torque to 21 in-lb or 2.38 N.m)
• 5/16 inch open-end torque wrench (torque to 10 in-lb or 1.13 N.m)
• ESD grounding wrist strap
Removal Procedure
Refer to Figure 7-14 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
3. Position the analyzer bottom side up.
4. Disconnect the ribbon cable (item
5. The attenuators and the brackets to which they are attached, must be removed as a complete assembly. 
Disconnect two semirigid cables (item
remove additional cables to remove the attenuator bracket. If so, note the location and orientation of each
for reinstallation later.
6. Remove four screws (item
7. Move the disconnected semirigid cables out of the way and lift the attenuator bracket out of the
analyzer, with the attenuator attached. It may be necessary to loosen the connector at the other end of
some of the semirigid cables to allow them to be moved enough.
8. Remove two screws from each attenuator to be removed from the mounting bracket.
Replacement Procedure
1. Reverse the order of the removal procedure.
Orient the position of the attenuators and brackets as shown in
Torque all cable connections to 10 in-lbs.
2. Perform the post-repair adjustments, verifications, and performance tests that pertain to this removal
procedure. Refer to Table 7-2 on page
7-38
"Removing the Covers" on page
①
) from each attenuator to be removed.
➁
) from each attenuator to be removed. It may be necessary to
③
) that secure each attenuator bracket to the test set deck.
7-54.
PNA Series Microwave Network Analyzers
7-6.
Figure 7-15.
Service Guide N5227-90001
N5227A