A20 Lowband (E4447A Only) - Agilent Technologies PSA Series Service Manual

Assembly Replacement Procedures
RF Section E4446A, E4447A, E4448A

A20 Lowband (E4447A only)

Removal
1. Remove the A13 Front End Driver, A12 Synthesizer, and A11
Reference assemblies. The cable hold down wire will need to be
removed in order to remove the Synthesizer assembly.
2. Refer to Figure 11-24. Remove the semi-rigid cables W15, W37, W39,
W41, W54, W55, and W56. Cable W18 will be removed when the A20
Lowband and A30 FIFA are separated.
3. Refer to Figure 11-25. Using the T-10 driver, remove the 2 screws
(4) that attach the Lowband assembly to the instrument. the
Lowband and FIFA assemblies can now be removed from the RF
section as a unit.
4. Separate the FIFA from the Lowband assembly by removing the 2
screws (7).
5. Remove the bracket from the Lowband assembly. This allows cable
W18 to be removed from the Lowband assembly.
Replacement
1. Assure the flexible coax cable W18 from the 3rd Converter is routed
through the hole in the RF deck shield. Connect the cable to the
Lowband assembly.
2. Replace the bracket on the Lowband assembly, and attach the FIFA
to the bracket. Torque the screws to 9 inch pounds.
3. Place the Lowband and FIFA assemblies into position in the RF
section and attach with the two screws removed in
4. Replace all semi-rigid cables removed from the RF section. Torque to
10 inch pounds.
5. Assure the flexible coax cable from the Lowband to the 3rd
Converter is routed along the motherboard so it will not get
damaged when the 3 assemblies removed earlier are replaced. Also,
assure there is no slack in the cable from the Lowband connector to
where the cable goes through the RF section shield.
6. Replace the 3 board assemblies, attach all cables, and the cable hold
down wire.
344
step 3 above.
Chapter 11