pulse amplifier assemblies, and a power supply
assembly. There are two independent equipment
groups in the AN/SSW-1D/E. Each group is capable
of simultaneous operations with separate and
dedicated computer input-output channels and
dedicated UHF radio sets.
Coordinate Data Transfer Control
The coordinate data transfer control assembly
enables the connection of each of the digital-to-digital
converters (DDC) to one of two different computers.
The control panel for the coordinate data transfer
control assembly is shown in figure 6-5. The
COMPUTER SELECT provides switching, such that
DDC A is connected to computer 1 and DDC B is
connected to computer 2 or vice versa. Either of the
two DDCs maybe connected to its monitor test panel
for off-line testing. The DDC output options are the
CDS (old NTDS) radio set, the CAINS system, or the
test mode.
Digital-to-Digital Converter
The digital-to-digital converter assembly provides
system timing, converts parallel data from the CDS
computer into serial data for transmission by the UHF
radio set, and converts serial data received from the
radio set into parallel data for input to the CDS
computer. The DDC is the heart of the data terminal
set.
Monitor Test Panel
The monitor test panel provides the technician
with a means to monitor Link-4A operations and off-
line testing capabilities. There is one monitor test
panel for each DDC.
Pulse Amplifier
The pulse amplifiers provide level and signal
conversion functions to allow the AN/SSW-1D/E data
terminal set to drive the serial output for the UHF
radio set and the deck edge outlet boxes for CAINS.
COMMUNICATIONS SWITCHBOARD
The communications switchboard interconnects
the AN/SSW-1 to the UHF radio sets. The
communications switchboard is similar to the Link-11
switchboard described in chapter 4 of this manual.
LINK MONITOR SYSTEM (LMS-4)
The LMS-4 provides stand-alone Link-4A monitor
and readiness check capabilities, and its operation is
similar to the LMS-11 covered in the previous
chapter. The monitor function listens passively to the
Link-4A communications between the control station
and the controlled aircraft. Signal analysis and test
message validity are performed on the data. The
readiness check function tests the readiness of the
control station to conduct live two-way Link-4A
operations. Control messages transmitted by the
control station are monitored and the LMS-4
generates the reply messages required to maintain
two-way communications.
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