Chapter 3 171
Assembly Replacement
Procedure 5. A2, A3, A4, and A5 Assemblies
Procedure 5. A2, A3, A4, and A5 Assemblies
Removal
1. Remove the spectrum analyzer cover.
2. Place the spectrum analyzer on its right side frame.
3. Remove the eight screws holding the A2, A3, A4, and A5 assemblies
to the top of the spectrum analyzer. These screws are labeled (2), (3),
and (4) in Figure 3-8 on page 172. They are also labeled on the back
of the A2 board assembly.
4. Remove ribbon cable W4 from A2J6. See Figure 3-8 on page 172.
CAUTION Do not fold the board assemblies out of the spectrum analyzer one at a
time. Always fold the A2 and A3 assemblies as a unit and the A4 and
A5 assemblies as a unit. Folding out one assembly at a time binds the
hinges attaching the assemblies and may damage an assembly and
hinge.
5. The board assemblies are attached to the right side frame of the
spectrum analyzer with two hinges. Fold both the A2 and A3
assemblies out of the spectrum analyzer as a unit.
6. Fold both the A4 and A5 assemblies out of the spectrum analyzer as
a unit.
7. Remove the cables from the assembly being removed, as illustrated
in Figure 3-9 on page 173.
8. Remove the two screws that attach the assembly being removed to
its two mounting hinges.
CAUTION Do not torque shield TORX screws to more than 8 inch-pounds.
Applying excessive torque will cause the screws to stretch.
NOTE Diagrams that illustrate features common to E-series and EC-series
instruments are shown with E-series instruments. Where there are
differences between E-series and EC-series features separate diagrams
are provided.