OF HIGH VOLTAGE MODULE ASSEMBLY 1A13
Refer to figure 3-55. Use a No. 1 Phillips screwdriver to loosen and remove the four cover retaining
screws that secure the cover to the frame assembly. Remove cover.
Use a No. 1 Phillips screwdriver to loosen and remove the four PWB retaining screws, lockwashers,
and flatwashers that secure High Voltage Module PWB Assembly 1A13A1 to the frame assembly.
The pwb can now be lifted away from the frame assembly for component replacement. If complete
removal of the pwb is required, tag all leads before unsoldering from pwb.
Use a No. 1 Phillips screwdriver and a four-inch adjustable wrench to loosen and remove the two
rectifier retaining screws, four flatwashers, two lockwashers, and two hex nuts that secure rectifier
sub-assemblies 1A13CR1 and CR2 to the frame assembly. If complete removal of the rectifier
sub-assemblies is required, tag all leads before unsoldering.
Use a No. 1 Phillips screwdriver to loosen the captive screw that secures the capacitor clamp to the
frame assembly. Remove the capacitor clamp and its captive screw. Fixed capacitor 1A13C1 is
now free from the frame assembly. For complete removal of capacitor 1A13C1, tag the leads, and
use a four-inch adjustable wrench to loosen and remove the two hex nuts and flatwashers that
secure the wiring harness terminal lugs to the capacitor posts. Slip the terminal lug off the capacitor
3-137. COMPONENT LOCATION DRAWINGS
3-138. Figures 3-29 through 3-64 comprise the component
location drawings applicable
to all power
amplifier assemblies and sub-assemblies. Refer to these drawings as necessary for component location and
orientation information. Table 3-12 presents a cross-reference of power amplifier subassembly component/
schematic illustrations and their applicable reference designations and part numbers.
3-140. The following information and procedures
should be followed when replacing components
repairing pcb/pwb assemblies.
Use a pencil-type soldering iron with a 25-watt maximum capacity. If only ac-operated soldering
Do not use a high wattage soldering gun for printed wiring board repair.
A high wattage gun can induce damaging voltages into the components
and will reach a very high temperature in a few seconds, causing damage
to the components and/or printed circuit/wiring boards.
When soldering solid-state devices, solder them quickly. Where space permits, use a heat sink (such
as an alligator clip or needle-nose pliers) between the joint to be soldered and the component lead
to conduct heat away from the component.
Excessive heat or pressure can cause the pcb/pwb copper runs to lift from the board. If this should
occur, re-cement the strip in place using a quick-drying acetate base cement or an epoxy resin having
good electrical insulating properties.
A break in the copper or copper strip of a pcb/pwb can be repaired by soldering a short length of
tinned copper wire across the break.
Use only high quality resin core solder when repairing printed circuit/wiring boards. Never use acid
core solder or paste flux.