Agilent Technologies E4440A, Service Manual

Page: 373 / 436

Chapter 11 373
Assembly Replacement Procedures
Vertical Board Assemblies (Standard Instrument)
Refer to the silkscreened locations on the motherboard or the top
brace to ensure correct placement of the assemblies. Hook the
ejectors under the tabs on the rear frame and mid web. Carefully
push down on the ejectors to mate the assembly with the
motherboard connectors. If the A7 Digital IF ejector handles do not
lay flat against the assembly casting, the assembly my not be
inserted fully and may cause EEPROM self-test failures.
2. Reconnect the cables that were removed. Refer to the silk-screen on
the instrument top brace, along with the matching numbers on the
cables and near the connectors on the boards, for correct placement
of cables. Torque any semi-rigid cables to 10 inch pounds. Take care
to dress the cables correctly so they aren’t pinched when the top
brace is replaced.
For correct routing of Option 122 or 140 cables, refer to Figure 11-42
on page 371 .
3. If the A12 LO Synthesizer assembly was removed, replace the two
screws and torque to 9 inch pounds. Replace the cable hold down by
inserting the end into the hole in the Midweb and secure it with the
single screw. Torque to 9 inch pounds.
4. Replace the instrument top brace and outer case. Refer to the “Top
Brace” and the “Instrument Outer Case” replacement procedures.