Keysight N5224B, Service Manual

Page: 571 / 614

Keysight N5224B/25B Service Guide 7-65
Repair and Replacement Procedures
Removing and Replacing the A71–A74 Bias Tee Combiners
Removing and Replacing the A71–A74 Bias Tee Combiners
Tools Required
— T-6 TORX driver - set to 6 in-lbs (0.68 N.m)
— 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 10 in-lb or 1.13 N.m)
— 5/16-inch open-end wrench (to stabilize the bias tee combiner when
torquing cables)
— ESD grounding wrist strap
Removal Procedure
Refer to Figure 7-33 on page 7-67 , Figure 7-34 on page 7-67 , Figure 7-35 on
page 7-68 , Figure 7-36 on page 7-68 , and Figure 7-37 on page 7-69 for this
procedure.
1. Disconnect the power cord.
2. Remove the outer cover. Refer to “Removing the Covers” on page 7-7 .
3. Position the analyzer bottom side up.
4. Disconnect the two semirigid cables (item

and

) from the bias tee
combiner to be removed. Refer to Figure 7-33 on page 7-67 .
5. Remove two screws from the bias tee combiner and bracket-to-chassis
assembly to be removed (Do item

only). Refer to Figure 7-34 on
page 7-67 .
Do not remove the bias combiner from the bracket yet (item

is done in
step 7 ).
6. Make note of the orientation of the two cable wires and ground cable
clamp for reinstallation later.
— Remove the DC bias cable (item

) from the Bias Combiner. Refer
to Figure 7-33 on page 7-67 . See also Figure 7-35 on page 7-68 .
— Remove the screw, cable ground clamp, and RF cable (item

) from
the Bias Combiner. Refer to Figure 7-33 on page 7-67 . See also
Figure 7-36 on page 7-68 .
7. Remove two screws that attach the bias tee combiner to the bracket (Now
do item

). Refer to Figure 7-34 on page 7-67 .
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.