Removing And Replacing The A27 And A28 Mixer Bricks - Keysight N5224A Service Manual

Repair and Replacement Procedures

Removing and Replacing the A27 and A28 Mixer Bricks

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.
CAUTION 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.
1. Disconnect the power cord.
2. Remove the outer cover. Refer to
3. Position the analyzer bottom side up.
4. Disconnect all semirigid cables (item
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
6. Remove two screws (item
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
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
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
b. Remove 3 screws (not shown) that fasten each mixer brick to the mixer brick mounting block.
7-34
"Removing the Covers" on page
①
) from each of the mixer bricks and the A26 splitter. 2-port
➁
) from each of the mixer bricks.
③
) from each end of the mixer brick bracket.
Chapter 6.
⑤
) from each shield.
PNA Series Microwave Network Analyzers
N5224A and N5225A
7-6.
④
) to be disconnected. It may be
Service Guide N5225-90001