LOOPBACK TEST 4.— Loopback test 4 is used
to check the operation of the computer interface, the
crypto device, and the data terminal interface
circuitry. When this test is selected, the audio circuits
are disabled and the data from the computer is sent to
the memory in the data terminal. Upon receipt of the
end of transmit signal, the data in memory is sent
back to the computer for evaluation.
DTS FAULT ISOLATION TESTS.— The DTS
fault isolation tests are built-in tests (BIT) designed to
test and isolate a fault to a particular circuit board.
REMOTE CONTROL UNIT
The C-12428/USQ-125 remote control unit (CU)
enables the operator to control the data terminal from
a remote location. The control unit, used with the
data terminal, forms the data terminal set (DTS). The
control unit is used by the operator to enter operating
parameters, to start and stop link operations, and to
change link modes. One model, shown in figure 5-4,
consists of a 486DX2/66 MHz AT compatible
personal computer in a rugged chassis for shipboard
operation. The keyboard/trackball unit is in a special
detachable enclosure that also serves as a front cover
for the CU. A 386 or better personal computer may
be substituted for the control unit when loaded with
the proper software and connected to the data
terminal.
JOINT TACTICAL INFORMATION
DISTRIBUTION SYSTEM (LINK-16)
The Joint Tactical Information Distribution
System (Link-16) is a new tactical data link that was
introduced to the fleet in 1994. Link-16 has been
referred to by several names and acronyms. Tactical
Digital Information Link (TADIL) is a term used by
the U. S. Joint Services. The TADIL designation for
Link-16 is TADIL J. The Joint Tactical Information
Distribution
System (JTIDS) refers to the
communications component of Link-16.
The
communications component includes the terminal
software, hardware, RF equipments, and the
waveforms they generate. The NATO term for JTIDS
is the Multifunctional Information Distribution
System (MIDS). For our purposes, we will use the
term Link-16 when referring to this system.
FEATURES OF LINK-16
Link-16 allows for the exchange of real-time
tactical information between units of the Navy, the
Joint Services, and the members of NATO. Although
some of the functions are identical to the functions of
Link-11 and Link-4A, Link-16 also provides data
exchange elements that the other link systems lack.
These include the following:
Nodelessness
Jam resistance
Flexibility of communication operations
Separate transmission and data security
features
Increased numbers of participants
Increased data capacity
Network navigation features
Secure voice capabilities.
Figure 5-4.—The C-12428/USQ-125 Control Unit.
5-4
