zero, one, two, or three grid points.
The Z
(unblank) signal unblanks the beam when active.
The W (wait) output is used to ensure the
completion of a stroke before the start of the next
stroke. The W fiction is normally used to ensure
the CRT beam is in the proper position before the
beam is unblanked, blanked, or makes a major
change in direction. This prevents distortion of the
symbol that could result if the beam has not
completely finished a stroke or has not been
completely repositioned.
Referring to figure 1-12, the PROM is addressed
and the output is translated. In this example, the
first stroke (stroke zero) positions the CRT beam
three grid spaces in the -X direction and the beam is
blanked. Upon completion of this stroke, the next
address is read and translated. Strokes one, two,
and three each cause the beam to be deflected one
grid space in the +X direction and two grid spaces
in the +Y (up) direction while the beam is
unblanked. At the end of stroke three, there is a
pause (W) so the beam can finish the stroke before
changing direction.
Strokes four, five, and six each cause the beam
to move one grid space in the +X direction and two
grid spaces in the -Y (down) direction. Again at the
end of stroke six, there is a pause (W) to ensure that
the beam deflection is complete.
When the PROM address for stroke seven is
read, no outputs are found active. This condition
signals the logic that the symbol is complete, and
the symbol generator moves to the next fictional
time period, as shown in table 1-1.
DISPLAY SYSTEMS
The combat direction systems (CDS) in use on
most ships evolved from the original NTDS systems.
These systems developed the standards for several
digital computer protocols, and the term NTDS is
still used to define several of these protocols. The
display sub-system is the largest part of the CDS
system.
Two major tactical display systems are currently
used in the fleet. These are the Data Display Group
AN/UYA-4(V) and the Computer Display Set
AN/UYQ-21(v).
Within each system different
versions are tailored for each class of ship,
according to the mission of the ship.
DATA DISPLAY GROUP AN/UYA-4(V)
The Data Display Group AN/UYA-4(V) is the
most widely used system currently in the fleet. It
was developed to refine the limitations of the
AN/SYA-4(V) and the AN/UYA-1(V) systems. The
AN/UYA-4(V) display group uses third generation
electronics (integrated circuit) for all logic functions.
The function of the Data Display Group
AN/UYA-4(V) is to provide a real-time visual
picture of the tactical situation. To perform this
requirement, the systems must be able to accomplish
several tasks including the following:
Sensor data distribution and display
Tactical data distribution and display
System simulation and testing
Figure 1-13 illustrates a typical AN/UYA-4(V)
display group. Sensor position data is received from
the ship’s sensor platforms (radar and sonar) and
sent to a converter for conversion into a form that
can be used by the display console. The converted
position data is routed to the display console through
a distribution switchboard. Sensor video data is
routed to the display consoles through the same
switchboard.
Tactical data is digital data received from or
transmitted to the system computer. Tactical data
from the computer is used by the display system to
generate symbol displays and alert/switch indications
on the display consoles.
Tactical data sent to the
computer is the result of some type of operator
action at the display console.
System test is accomplished with the system
computer and the video signals simulator (VSS). As
illustrated in figure 1-13, the VSS can simulate a
radar input to the switchboard to aid the technician
in fault isolation or provide simulated data for
operator training.
The tactical data paths can be
tested using the various software programs (POFA,
PEFT, etc.) designed to run with the system on your
ship.
1-13
