TM 9-4931-436-14&P
Device,
Direct Support Troubleshooting Table - continued
Table 5-1.
Alignment
CORRECTIVE
ACTION
TEST OR INSPECTION
MALFUNCTION
Use programmer test set,
INCORRECT RESPONSE
10.
and transmitter test set
ON TWO DISPLAYS;
fitted with aperture
ONE ON VERTICAL
adapter to test detector
AXIS; ONE ON
HORIZONTAL AXIS
array.
1. Replace defective
Step 1. Test preamplifier
(Refer to fig. 5-2,
boards in line with both
preamplifier board.
retest per chapter 7)
horizontal and vertical
coordinates in shared quad-
rant as shown in figure 5-3.
Board not receiving signal
from defective detector
will show no pulse when
detector is illuminated.
NOTE
When both displays asso-
ciated with one cross
point show incorrect
responses, a detector at
that cross point is
usually at fault.
2. Replace defective
Step 2. Test for defective
detector.
detector by firing at each
cross point in the appro-
priate quadrant of the
detector array that can
affect the preamplifier
board isolated in step 1.
3. Replace input board
Step 3. Test input board
A1.
Al by substitution.
1. Replace wiring
1. Inspect for broken wire.
FIXTURE DOES NOT
11.
cable assembly.
TURN OFF AUTOMATICALLY
2. Resolder connection,
2. Inspect for bad solder
(Refer to fig. 5-2,
connection.
retest per chapter 7)
3. Tighten or replace
3. Inspect for loose
cable assembly.
connector .
4. Replace A2A2.
4. Test for defective
timing logic board A2A2.
5. Replace A2A3.
5. Test for defective
microprocessor logic
board A2A3.
5-5
