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The card designation (A1 thru A8) is a part of the equipment
designators of the card-installed electronic parts for their correct
identification in the UUT (e.g., A1IC100, A3IC301 and A8IC501).
Page 138.04
Feb 20/2002
Matsushita Avionics Systems Corporation
COMPONENT MAINTENANCE MANUAL
PART NUMBER RD-AA5002 SERIES
23-32-47
(10) Electrostatic discharges from your hands or tools can cause
permanent damage to most of the semiconductor devices on the printed
circuit card assemblies. Obey the general precautions given below
to prevent such damages:
· Do the disassembly and assembly work on a grounded conductive
surface.
· Put on a conductive wrist-strap that is grounded.
· Touch your tool to the ground (grounded metal structure, etc.)
before you use it.
· Use a tip-grounded soldering iron.
· Put the removed printed circuit board assembly on a grounded
conductive surface.
(11) The logic signal levels are as follows:
SIGNAL CONDITION SIGNAL VOLTAGE LEVEL (TO GROUND)
H (High) Approximately the positive supply voltage.
L (Low) Approximately the ground potential (0 V).
Page 138.05
Feb 20/2002
Matsushita Avionics Systems Corporation
COMPONENT MAINTENANCE MANUAL
PART NUMBER RD-AA5002 SERIES
23-32-47
C. Fault Isolation Data
The fault isolation data is given below as a table (Fault Isolation
Table), for which we use the assumptions given below:
· The cause of malfunction is one, not two or more.
· The UUT was satisfactory in all checks and items until you found it
unsatisfactory.
The ITEM column of the Fault Isolation Table shows the paragraph
identification of the step or check in which the UUT was found
unsatisfactory.
The SYMPTOM column gives a specific type of problem that you possibly see
in the testing.
The FAULT ISOLATION column gives fault isolation instructions. It also
gives the parts, circuits, circuit blocks or assemblies that can be the
cause of the trouble given. We will refer to one of the fault isolation
procedures (D. and after) or the adjustment procedure (7.) in this column
if applicable.
Page 138.06
Feb 20/2002
Matsushita Avionics Systems Corporation
COMPONENT MAINTENANCE MANUAL
PART NUMBER RD-AA5002 SERIES
23-32-47
Fault Isolation Table
ITEM SYMPTOM FAULT ISOLATION
4.C.(2)
(b)
You do not hear the 400-Hz hum
from the UUT or the fan above
the J1 connector does not turn.
Go to Fault Isolation Procedure for
Power Supply (D.).
4.C.(3)
(f)
The amplitude of the video
signal does not increase, but
stays unchanged.
There is an open-circuit fault
between the tester's VIDEO INPUT CH1
connector and the UUT's CH1 A2 card.
Find the fault and repair.
5.A.(8) The communication function of
the UUT is defective.
Go to Fault Isolation Procedure for
Communication Error (E.).
5.A.(9) The UUT's one channel is
defective.
Go to Fault Isolation Procedure for
A2 Card Failure (G.).
5.A.(9) The UUT's two or more channels
are defective.
Go to Fault Isolation Procedure for
A1 Card (H.).
5.B.(1) There is no RF carrier for one
channel.
Replace the A2 card for this channel
with that for a different channel.
If the RF carrier shows on this
channel, the fault is on the A2 card
(the power control circuit or RF
circuit).
If there is no change in the results,
the fault is possibly on the A5 card
(the related PC line).
5.B.(4)
thru
5.B.(9)
The VMU tuner gives no video
output for one channel.
The video input circuit (A2IC201) on
the A2 card for this channel is
possibly defective.
5.B.(4) The video input level is less
than 0.7 Vp-p or more than 1.3
Vp-p (RD-AA5002-23 or
RD-AA5002-25 only).
Incorrect position of the A2 cards.
For RD-AA5002-23, the 100-W input A2
card must be connected to the A5CN18
connector.
For RD-AA5002-25, the 100-W input A2
cards must be connected to the A5CN13
thru A5CN18 connectors.
5.B.(8) The video output is less than
0.9 Vp-p or more than 1.1 Vp-p.
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 (7.).
Page 138.07
Feb 20/2002
Matsushita Avionics Systems Corporation
COMPONENT MAINTENANCE MANUAL
PART NUMBER RD-AA5002 SERIES
23-32-47
Fault Isolation Table (Cont'd)
ITEM SYMPTOM FAULT ISOLATION
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COMPONENT MAINTENANCE MANUAL Video Modulator Unit (VMU)(39)
