designed to check particular functions of the display
consoles and VSS. The display POFA is normally
run on a group of consoles as part of the fault
isolation process or as required by the planned
maintenance system (PMS).
The display POFA subtests will vary from
system to system, depending on the equipment
configuration of the display suite.
however, several common functions normally tested.
Switch function codes are checked; test patterns of
symbols are displayed; the trackball/ball tab coor-
dinates are verified; and various panel operations are
exercised. The display POFA is designed to com-
pletely check all display capabilities.
The display PEFT grouping of subtests is
contained in the operational program. The display
PEFT allows the operator or technician to verify the
operation of a single console independent of the
operational program in progress.
The display PEFT subtests are similar to the
display POFA. However, the range of subtests is
more limited in the PEFT. The display PEFT is
designed to be run on a console in the event a
console malfunctions during normal operations.
CIRCUIT TEST SET
Tactical display systems are equipped with an
electronic plug-in circuit test set.
The test set,
shown in figure 3-26, provides the technician with
the facilities to test and repair faulty plug-in
assemblies used in the display suite equipments.
The test set simulates normal operating
conditions by providing operating power and loads
to the assemblies under test. In addition, the test set
provides test signals and monitoring facilities, which
enable the technician to troubleshoot, test, and align
Portable test equipment (oscil-
loscopes, vacuum tube voltmeters, and so forth) is
used in conjunction with the test set.
SUMMARYTHE DATA DISPLAY
This chapter has introduced you to the Data
Display Group AN/UYA-4(V).
information summarizes the important points you
should have learned.
DATA DISPLAY GROUP The purpose of any
display system is to present a visual picture of the
tactical situation. This allows the operator to make
various decisions and take action. The heart of the
display system is the plan position indicator (PPI),
or display console. The PPI receives analog inputs
from the ships sensors (radar and sonar), digital or
tactical data from the CDS computer, and simulated
data from the video signals simulator (VSS) and test
message generator (TMG). The simulated data from
the VSS can be used for system testing or operator
SENSOR DATA DISTRIBUTION Sensor
data from the radar is received by the radar azimuth
converter (RAC) and distributed to the PPIs by the
radar data distribution switchboards.
R A D A R A Z I M U T H C O N V E R T E R
(RAC) The RAC converts antenna position data to
a form that the PPI can use. The azimuth data is
sent to the PPI console as DC and DU pulse trains.
The number of pulses in the pulse train represents
the angle of the antenna, and the spaces between the
pulses represent the range of the radar.
R A D A R D A T A D I S T R I B U T I O N
SWITCHBOARD (RDDS) The RDDS provides
amplifications of the radar video received from the
radar and the azimuth data received from the RAC
and distributes them to the PPI consoles.
TACTICAL DATA DISTRIBUTION AND
DISPLAY Tactical data is data generated by the
CDS computer. Tactical data can be symbol data or
amplifying information about a symbol. Depending
on the system installed on your ship, the tactical
data may be distributed through several different