doble M4000 series User Manual page 154

Replacing the Amplifier Assembly
N
OTE
4-64
Figure 4.33 Amplifier Assembly, Additional Screw Locations
5. Remove two Phillips screws (Figure 4.33) holding the top cover of the
amplifier and chassis in place using a Phillips-head screwdriver.
6. Disconnect the ribbon cable (W7) from the Guard Board, which is located
in the card cage.
7. Release the three white connectors (leading to cables W2, W3 and W4)
from the front side of the Amplifier Assembly, closest to the Transformer.
Work from right to left, ending with the white connector closest to the card
cage.
8. Insert two fingers into the two notches at the top of the Amplifier
Assembly to ease it out. Then, grasp the edges of the assembly and
carefully lift it out of the instrument.
The clearance around the Amplifier Assembly is only about 1/8 inch. If
the assembly is difficult to remove, insert a flat-blade screwdriver around
its perimeter to gently pry it out.
9. Unpack the replacement Amplifier Assembly.
10. Insert two fingers into the notches at the top of the new Amplifier
Assembly and gently guide it into position.
Top Fan Screws
72A-1230 Rev. F
Side Screws