Keysight Technologies N5224A, Руководство по обслуживанию

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7-36 Keysight N5224A/25A Service Guide
Repair and Replacement Procedures
Removing and Replacing the A27 and A28 Mixer Bricks
7-
Removing and Replacing the A27 and A28 Mixer Bricks
Tools Required
— T-8 TORX driver (torque to 6 in-lb)
— T-10 TORX driver (torque to 9 in-lb)
— T-20 TORX driver (torque to 21 in-lb)
— 5/16 inch open-end torque wrench (torque to 10 in-lb)
— ESD grounding wrist strap
Removal Procedure
Refer to Figure 7-16 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 all semirigid cables (item
①
) from each of the mixer bricks and
the A26 splitter. 2-port models have only one mixer brick, A27, and no A26
splitter; 4-port models have two mixer bricks, A27 and A28, and the A26
splitter.
5. Disconnect the ribbon cables (item
➁
) from each of the mixer bricks.
6. Remove two screws (item
③
) from each end of the mixer brick bracket.
7. Move the disconnected semirigid cables out of the way and lift the mixer
brick mounting block out of the analyzer just enough to allow the gray
flexible RF cables (item
④
) to be disconnected. 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.
Note the locations of each of the gray flexible cables for reconnection
later. If necessary, refer to the appropriate bottom cable illustration in
Chapter 6 .
Disconnect these cables and remove the mixer brick mounting block, with
the mixer brick(s), the mixer brick shields, and the A26 splitter attached,
from the analyzer.
8. If replacing a mixer brick:
a. Remove the two screws (item
⑤
) from each shield.
Be careful not to damage the center pins of the semirigid cables. Some
flexing of the cables is necessary to remove assemblies but do not
over-bend them.