TM 11-5820-890-30-4
Section IV. MAINTENANCE PROCEDURES
Subject
Para
General
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12-25
Operational Check .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
12-26
Repair Procedures
.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
12-27
Replacement of RCU Covers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
12-28
Replacement of Modules 19A2, 19A3, 19A4, 19A5, 19A6, 19A7, 19A8,
19A9, 19A10, and 19A11
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
12-29
Replacement of
Replacement of
Replacement of
Replacement of
Replacement of
Replacement of
Replacement of
Replacement of
Replacement of
Replacement of
Replacement of
Power Supply (19A1)
. . . . . . . . . . . . . . . . . . . . . . . .
DC Power Filter (19A12) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Front Panel/Chassis (19A13) . . . . . . . . . . . . . . . . . . . . . . . . . . .
Data Entry Keypad
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Front Panel Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Audio Flex
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Switch Flex .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Display CCA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Front Panel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Observation Window . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Threaded Screw Inserts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
12-25. GENERAL.
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12-31
12-32
12-33
12-34
12-35
12-36
12-37
12-38
12-39
12-40
Page
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This section includes the operational check and the repair procedures. The operational check is used to verify
the operation of a repaired RCU. It is also used to verify the symptom of a faulty RCU. When a bad module is
identified, replace it using the procedures in this section.
12-26. OPERATIONAL CHECK.
Perform the operational check in paragraph 12-23 to verify correct RCU operation.
12-27. REPAIR PROCEDURES.
Repair of the RCU consists of replacing a bad module. A module is replaced by removing it and installing a good
module. Procedures for doing this follow.
a. General instructions. The following instructions apply to all repair tasks.
1.
Set the RCU FCTN switch to , and set the test adapter PTT switch to OFF.
2. Remove any cables connected to the RCU.
3. Inspect the RCU for damage. Repair any obvious physical damage.
4. Use the module extractor to remove the circuit card assemblies. It is included in the maintenance
tool kit. It is used as follows:
(a) Locate the module to be removed.
(b) Hook the module extractor through the two holes in the top corners of the module.
(c) Hold the module extractor with one hand. Place the other hand on the RCU with the fingers of
that hand resting on top of the module to be removed.
(d) Pull steadily with the module extractor until the module connector is free of the parent board.
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