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4.C.(1) The video output is not in the
MIN-MAX limits for one channel.
First, make sure that the video input
level at the BNC tee adapter T1 is
1 Vp-p.
If the video input level is correct,
adjust the modulation depth. Go to
Adjustments (6.).
4.D. The picture on the video
monitor has diagonal stripes,
shows incorrect colors, etc.
There are many causes for this type
of fault, and fault isolation is not
easy without special instruments.
4.E. You do not hear a "click" or
you are not sure if you heard a
"click" during the change from
the video quality check to the
BITE function check.
First, make sure that there is no
"click" during the change from the
video quality check to the BITE
function check as follows:
· Click on the "BACK" button to go
back to the video quality check.
· Click on the "NEXT" button after
all frequency values are shown, and
listen for the "click".
If there is no "click", make sure
that the TG CONT signal at the
A8CN508 connector is L, then examine
the A8Q504/A8IC504 circuit to find a
fault.
4.E.(3) There is no video output and no
picture on the video monitor.
Examine the video generator circuit
on the A8 card to find a fault. If
the white raster video output goes to
A8RL501, replace A8RL501.
4.E.(4) The video output level is less
than 0.75 Vp-p or more than
0.95 Vp-p.
Adjust A8VR501 and A8VR502 (Figure
110) or A8VR501 (Figure 110A). Go to
Adjustments (6.).
4.F. You hear only one "click"
during the change from the BITE
function check to the channel 1
input selection check.
Examine the A1IC114 output. A1IC114
is possibly defective if it is L. If
A1IC114 output is H, A5RL1 is
possibly defective.
4.F.(9) You heard two "clicks", but
there is no video output and no
picture on the video monitor.
A5RL1 is possibly defective.
T&FI-2
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Feb 20/2002
Matsushita Avionics Systems Corporation
COMPONENT MAINTENANCE MANUAL
PART NUMBER RD-AA5002 SERIES
23-32-47
CAUTION: DO NOT USE THE OSCILLOSCOPE FOR FAULT ISOLATION OF THE PRIMARY AND
SECONDARY CIRCUITS OF T1 AND T2, OR A SHORT-CIRCUIT FAULT WILL
OCCUR THROUGH THE OSCILLOSCOPE GROUND.
E. Fault Isolation Procedure for Power Supply (A6 Card, T1, T2 and A4 Card)
NEXT STEP IF
STEP CHECK/POSSIBLE FAULT
YES NO
E-1 Do you hear the 400-Hz hum from the UUT? E-3 E-2
E-2 Do a continuity check of the AC power lines between the
J1 and A6CN2 connectors to find a fault. If the AC power
lines are good, examine A6F1 and A6F2. If they are open,
examine the circuit after them for a short-circuit fault
and repair, then replace them. --- ---
E-3 Does the fan above the J1 connector turn? E-5 E-4
E-4 Examine the A4 card for -9V output at A4CN402. If no -9V
output, examine the +9V power circuit on the A4 card to
find a fault. If there is a -9V output, replace the fan
assembly. --- ---
E-5 Examine the A4 card for +8V, +32V and +24V outputs to
find a fault. --- ---
T&FI-2
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Feb 20/2002
Matsushita Avionics Systems Corporation
COMPONENT MAINTENANCE MANUAL
PART NUMBER RD-AA5002 SERIES
23-32-47
F. Fault Isolation Procedure for Communication Error
Do the procedure given below after you do the fault isolation procedure
for power supply (E.) to make sure that the UUT's power circuits are
satisfactory.
NEXT STEP IF
STEP CHECK/POSSIBLE FAULT
YES NO
F-1 Prepare the UUT to get access to A1IC104. Start the
tester program again and monitor the data input at pin 13
of A1IC104.
Is there a data signal at pin 13 of A1IC104 when you see
the "USER CONFIGURATION" window? F-3 F-2
F-2 There is an open- or short-fault in the RS-232C data
input line. --- ---
F-3 Monitor the data output at pin 14 of A1IC104. Click on
the "CONTINUE" button" of the "COMMUNICATION ERROR" box
to start the data communication.
Is there a data signal at pin 14 of A1IC104? F-4 F-5
F-4 There is an open- or short-circuit fault in the RS-232C
data output line. --- ---
F-5 Do the same check as F-1 at pin 12 of A1IC104. If there
is no data signal at pin 12 of A1IC104, replace A1IC104.
If there is a data signal at pin 12 of A1IC104, do the
same check as F-3 at pin 11 of A1IC104.
If there is no data signal at pin 11 of A1IC104, go to
Fault Isolation Procedure for Microcontroller (G.).
Replace A1IC104 if there is a data signal at its pin 11. --- ---
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COMPONENT MAINTENANCE MANUAL Video Modulator Unit (VMU)(77)
