Keysight Technologies N5247B, Service Manual

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Keysight N5247B Service Guide 7-43
Repair and Replacement Procedures
Removing and Replacing the A29 –A32 Reference Couplers and Reference Coupler
Mounting Brackets
Removing and Replacing the A29 –A32 Reference Couplers and
Reference Coupler Mounting Brackets
Tools Required
— T-6 TORX driver (set to 4 in-lb)
— T-10 TORX driver (set to 9 in-lb)
— 5/16 inch open-end torque wrench (set to 10 in-lb)
— ESD grounding wrist strap
Removal Procedure
Refer to Figure 7-20 for this procedure.
1. Disconnect the power cord.
2. Remove the outer cover. Refer to “Removing the Covers” on page 7-6 .
3. Position the analyzer bottom side up.
4. Disconnect three semirigid cables (item

) from the reference coupler to
be replaced.
5. Remove three screws (item

) from the mounting bracket of the reference
coupler to be replaced.
6. Move the disconnected semirigid cables out of the way and lift the
reference coupler mounting bracket, with the reference coupler attached,
out of the analyzer. 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.
7. Remove four screws that attach the reference coupler to be replaced to
the reference coupler mounting bracket, and remove the reference coupler
from the bracket.
Replacement Procedure
1. Reverse the order of the removal procedure.
Orient the position of the reference couplers and brackets as shown in
Figure 7-21 .
Torque all RF connectors 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 7-92 .
Be careful not to damage the center pins of the semirigid cables. Some
flexing of the cables is necessary to remove the assembly. However, do not
over-bend the semirigid cables.