Keysight Technologies N5224A Service Manual page 303

Repair and Replacement Procedures
Removing and Replacing the A27 and A28 Mixer Bricks
Replacement Procedure
1. Reverse the order of the removal procedure.
2. Perform the post-repair adjustments, verifications, and performance tests
Figure 7-16 A27 and A28 Mixer Bricks Removal
Keysight N5224A/25A Service Guide
b. Remove 3 screws (not shown) that fasten each mixer brick to the
mixer brick mounting block.
If replacing the A28 mixer brick, remember to move the dust
cap/termination (item
in the same location.
Some 2-port models and some 4-port models have a 3-dB pad on the A27
mixer brick R1 connection and all 4-port models have a 3-dB pad on the
A28 mixer brick R4 connection. If appropriate, be sure to move the pad(s)
from the old mixer brick(s) to the new mixer brick(s).
Torque all RF cable connections to 10 in-lbs.
that pertain to this removal procedure. Refer to
⑥
) from the old mixer brick to the new mixer brick
Table 7-2 on page 7-59.
7-37