TM 11-5820-890-10-1
SECTION Ill. TECHNICAL PRINCIPLES OF OPERATION
ITEM
PAGE
Scope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..................... 1-15
General Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-15
Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 1-15
This section describes the various configurations of SINCGARS radio equipment. It
lists the types of data you need to perform SC and FH operations and in which channel
it must be loaded. It also describes why particular data is needed.
The MP, SR, SR-D, SR/LR, SR/LR-D, LR, and LR/LR (AN/PRC-119A and AN/
VRC-87A, 87C, 88A, 88C, 89A, 90A, 91A, and 92A) are radios in a family of VHF-FM
combat net radios designed to provide the primary means of command and control
(voice and digital data) for combat, combat service, and combat service support
units.The radios are designed to achieve commonality among the various configura-
tions. A common receiver-transmitter (RT) is used in the manpack and in all vehicular
configurations.
Your SINCGARS radio is capable of two modes of operation: Single channel (SC)
and frequency hopping (FH).
SINGLE CHANNEL: When using the SC mode of operation, the RT communicates
on one frequency (selected using RT keyboard) that has been loaded into the RT.
The SC frequency can be cleared or offset as desired.
FREQUENCY HOPPING: SINCGARS also has the ability to secure transmissions
through the use of a transmission security key and frequency hopping to reduce or
eliminate the threat of jamming and direction-finding equipment. In order for your
RT to use the FH mode of operation, it must be loaded with FH data. The data neces-
sary for FH operation are (1) cold start TSK, (2) SC frequency loaded into MAN
channel, (3) hopset( (4) lockout set(s), if required, and (5) FH sync time.
1. Cold Start TSK. Cold start TSK is the transmission security key (TSK),
which, when combined with proper switch settings will result in ‘COLD’
display. This means that the radio is ready for a cold start net opening.
To make the display show “COLD”, four things must occur: (1) MODE
switch set to FH or (2) cold start TSK loaded, (3) CHAN set to
MAN, and (4) MAN frequency loaded. The cold start TSK is a variable which
determines the sequence in which the RT hops during FH operation.
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