Removing And Replacing The A23 And A24 Mixer Bricks - Keysight N5221A Service Manual

Repair and Replacement Procedures

Removing and Replacing the A23 and A24 Mixer Bricks

Removing and Replacing the A23 and A24 Mixer Bricks
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 1.13 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. Remove cable W42 from between the A21 HMA26.5 and the A22 splitter.
5. Disconnect all semirigid cables (item
6. Disconnect the ribbon cables (item
7. Remove two screws (item
8. 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. Disconnect these cables
and remove the mixer brick mounting block, with the mixer brick(s) and A22 splitter attached, from the
analyzer.
9. If the A23 mixer brick is to be replaced, disconnect cable W43 from the A23 mixer brick.
If the A24 mixer brick is to be replaced, disconnect cable W44 and remove the short circuit termination
⑤
(item ) from the A24 mixer brick. Retain the short circuit termination for installation on the new mixer
brick.
10. Remove three screws that attach the mixer brick to be replaced to the mixer brick mounting block, and
remove the mixer brick from the mounting block.
7-34
"Removing the Covers" on page
①
) from each of the mixer bricks.
➁
) from each of the mixer bricks.
③
) from each end of the mixer brick bracket.
PNA Series Microwave Network Analyzers
7-6.
④
) to be disconnected. It may be
Service Guide N5222-90001
N5221A/22A