HEADQUARTERS OH-58A, Technical Manual

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TM 55-1520-228-10
3-32.2 Change 11
occurs the processor generates the appropriate threat
symbology and synthetic audio. It is important therefore
that the correct theaterized EID and UDM are installed
for the mission or geographic location.
(3) Symbol generation and position relative to
the center of the CRT shows the threat lethality, it does
not show or represent any liability of range, but of condi-
tion/mode of the emitter. Highest priority threats (most
lethal) are shown nearest the center. Each symbol de-
fines a generic threat type, symbols are modified to
show change in the status of the emitter. The symbols
are unclassified, the definitions of what the symbols
mean are classified. The complete set of symbols and
definitions are contained in TM 11-5841-294-30-2. Each
theaterized library EID has a specific classified pilot
kneeboard produced with it. The unit electronic warfare
officer (EWO) should contact PM-ASE if sufficient cards
are not available within his unit for the installed EID.
3-69. CONTROLS AND FUNCTIONS – RA-
DAR SIGNAL DETECTING SET (AN/
APR-39A(V)1).
Refer to figure 3-17.
3-70. OPERATING PROCEDURES – RA-
DAR SIGNAL DETECTING SET (AN/
APR-39A(V)1).
a. Self-Test Mode.
(1) After power up, the AN/APR-39A(V)1 syn-
thetic voice will announce “APR-39 POWER UP” and
the (+) symbol will stabilize in the center of the CRT. Self
test should be initiated after approximately one minute.
Self test can be performed in MODE ONE or MODE
TWO. In MODE ONE the synthetic voice will announce
“SELF TEST SET VOLUME, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10,
11, 12”. In MODE TWO the synthetic voice will an-
nounce “SELF TEST SET VOLUME, 5, 4, 3, 2, 1”.
(2) The CRT will display specific software ver-
sion numbers (i.e., operational flight program (OFP)) at
the 12 o’clock position and the emitter identification data
(EID) at the 6 o’clock position.
(3) After the software version numbers have
been displayed the test sequence checks the receivers.
A good visual self test will show two triangles, one at the
6 o’clock and one at the 12 o’clock position on the CRT.
Snowflake symbols (*) will appear at the 2, 4, 8, and 10
o’clock positions and will flash if the AN/AVR-2 laser
detecting set is not installed. This is a normal indication
and does not effect system performance.
(4) A good self test (no faults detected) ends
with the message “APR-39 OPERATIONAL”. A bad self
test (faults detected) ends with the “APR-39 FAILURE”.
b. MODE 1 Operation. Selecting MODE ONE the
operator will hear all the normal synthetic voice audio
when an emitter has been processed (e.g., the AN/
APR-39A(V)1 will announce; “SA, SA-18 12 O’CLOCK
TRACKING”). Selection of this mode does not have any
effect on emitters received, processed or displayed. It
only affects synthetic voice audio.
c. MODE 2 Operation. Selecting MODE TWO the
operator will hear an abbreviated synthetic voice audio
(e. g., the AN/APR-39A(V)1 will announce, “MISSILE 12
O’CLOCK TRACKING”).