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EN 50
5.
SACD 900
Key-Matrix
Connect a extra 10k( pull-up to pin 36 en 37 of the uP and
check next matrix scanning at these pins.
PM3392A
ch1:
low =-46.9mV
ch1
ch1:
high= 5 09 V
B
1
STOP
CH1 2.00 V=
MTB10.0ms
Figure 5-43
Level A: 5.0V ±7%
Level B: 0V ±200mV
Check matrix scanning from pin 26 until 33 of the uP.
The results should be the same as the diagram above.
I.R. Receiver
Check at pin 22 of 7401 if this line switches from low (< 0.3V)
to high (> 4.5V), while pressing a key on a Philips RC5 or RC6
remote control.
P50 Interface
P50 is a bi-directional serial interface, which is used for
communication between video equipment. For European sets,
this communication goes via pin 10 of the scart-bus. In other
regions, it can be a cinch bus at the back of the set.
1. Keep the uP in reset by short-circuiting emitter and
collector of transistor 7105, via resistor 3100 and 3107
transistor 7101 is switched on.
2. Check the voltage at the P50 output connector 1108-5: <
200mV.
When the reset is released the uP output-pin becomes low and
transistor 7101 is switched off.
1. Check the voltage at the P50 output connector 1108-5: 4V9
±5%.
2. Check also the uP P50 input (uP pin 20): 5V ±5%.
3. Connect the P50 line (connector 1108-5) to ground.
4. Check again the uP P50 input (uP pin 20): <0V3.
Diagnostic Software Descriptions and Troubleshooting
A
ch1-
CL 96532065 076 eps
130799
5.11 Test Instruction Audio/Video Board
These test instructions can be used for all versions of the A/V
board which has the following outputs:
•
Audio L/R
•
5.1 Audio output
•
Subwoofer output
•
Optical / Coaxial digital output
•
CVBS
•
Y/G_vid,U/B_vid,V/R_vid output
•
S-video
•
Scart output
5.11.1 General
•
All the waveforms measurement carried out in these test
instruction will be base on the testpoint indicated in the A/
V board schematic diagram in the Service manual.
•
Impedance of the measuring-equipment should be > 1MΩ
•
Most of the tests can be done using either the Diagnostic
software " Player script" which can be found in the chapter
"Diagnostic Software description and troubleshooting" or
the Menu interface using the Service PC with a terminal
emulation program ( e.g. Window Hyperterminal ) where it
is possible to control the execution of the Diagnostic Nuclei
•
Setup for the measurement will be done in set level with all
modules connected as shown in the Wiring Block diagram.
5.11.2 General Start-Up Measurement
Supply Check:
Before starting the measurement,ensure that all power supply
are connected to the A/V board.
Pin nbr
Supply
1405-9
-5V ( -Vcc )
1405-10
+5V
1405-11
+5V
The supply currents can be measured using a Tektronics
AM503B current probe or equivalent.
Supply
Power consumption ( AVG )
+5V ± 3% I = 200mA
+5VA
+5V ± 3% I = 200mA
+5Vvid
-5V ± 3% I = 200mA
-5V
Clock Check
Ensure the present of the clock to the DAC
Clock Name Testpoint Frequency
PCM_CLK
I165
384FS
I110
Audio Mute Check
Measure the Audio mute voltage input at pin 12 of connector
1405
Status
Value
AudioMuteOn 4.7V ± 10%
AudioMuteOff -8V ± 10%
To toggle between ON and OFF,use the following commands:
Command
Ref.#
Name
19a
AudioMuteOn Audio Mute On
19b
AudioMuteOff Audio Mute Off
5.11.3 Audio DAC And Amplifier
Ensure that the Audio mute signal is OFF
To check the DAC and buffer amplifier,send the following
commands:
11.2896MHz ± 0.02% tolerance
16.9344MHz ± 0.02% tolerance
Remarks
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