PREVENTIVE MAINTENANCE CHECKS AND SERVICES FOR SINCGARS REMOTE CONTROL UNIT (RCU) (cont)

TM 11-5820-890-10-8

Not Fully Mission

Operator

Item to

Item

Capable If:

Procedure

When Check/Service

Nr.

COMM CHECK:

Before

Sidetone is not heard.

Check for sidetone.

SC Mode

During

Cannot change RT

Check ability to change RT

FH Mode

After

channel from RCU

channel from RCU.

Plain Text

Cannot communicate

Check voice comm in

Cipher Text

in SC-PT/FH-CT

SC-PT and FH-CT****

Voice

voice

(Check SQ OFF while in SC

Data

mode from RCU.

mode).

Cannot communicate

If data comm is mission-

in mission-required

required, check data comm

data

in FH-CT, using

mode using mission-

mission-related data

related data device.

device.****

Check intercomm capability

between RCU and radio.

"Does not function proper/y"means that a control will not do what it is intended to do,

for example, turning the FCTN knob does not change the radio's function. It may be necessary to

wait until Item 7 (Communications Checks) to determine for sure that some controls do or do not

function proper/y.

"Damaged and cannot be used" meansthat after visual inspection or operational

check you determine that a piece of equipment, for whatever reason, is faulty and will not support

your mission requirements or presents a safety hazard.

***

Use of the ICOM fill procedure is appropriate here, but on/y COMSEC keys are loaded

into the RCU.

****

Skip steps "c" and "d" if unit SOP or tactical situation prohibits transmitting.

*****

Unless your mission is likely to require use of data mode, you do not need to perform

this check.

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