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Circuit diagram
CN1000 X701 16.9344MHz
59 58 78 73 E 75 A 44 IC702 DSP 1 64 15 Sub-code Q data 19 B 3 24 4 23 26 80 C 17 110
E
A 16 111 106
L ch Audio signal output IC701 8 SERVO R ch
a
5
b
IC1000 MPEG VIDEO AUDIO 3 DECODER
6
IC1003 INVERTER
X1000 27MHz
LCD
IC401 SYS CONT.
D 2 67
Video signal output CD-DA/ VCD(AUDIO) VCD(VIDEO) CD-DA/ VCD (AUDIO&VIDEO) Clock line
DATA SIGNAL LINE WAVEFORMS
A IC702 44 ARF
Note: Use the PVCD-K06 video CD test disc (menu playback feature is available on version 2.0). For color bar display, play back the 1st track when the menu playback feature is used, or the 3rd track when the feature is not used.
B IC1000 4 CD serial data input C IC1000 110 Audio serial data output
signal
T=0.354 s(F=2.822MHz)
T=0.48 s(F=2MHz)
0.8V
3.2V
6.2V
PLAY X:0.5 s Y:0.023Vx10
D IC1000 67 Video signal output
PLAY X:0.2 s Y:0.2Vx10 (color bar screen) H signal(PLAY, X:10 s, Y:0.1Vx10) 63.5 s
PLAY X:0.2 s Y:0.2Vx10
E IC702 73 , 75 Audio signal output
(blue back screen) H signal(PLAY, X:10 s, Y:0.1Vx10) 63.5 s 0.6V
T=1 s(F=1kHz)
1.2V
2.4V
8 s 8 s 8 s 8 s 8 s
8 s
Test disc played at 1kHz, 0dB (1st track SZZP1056C) PLAY X:1 s Y:0.1Vx10
V signal(PLAY, X:5 s, Y:0.1Vx10) 16.7 s 0.6V
V signal(PLAY, X:10 s, Y:0.1Vx10) 16.7 s
1.2V
MASTER CLOCK SYSTEM WAVEFORM
a
AUDIO DATA CLOCK SYSTEM WAVEFORM
A
Video read clock T=0.037 s
b Write reference clock
Audio bit clock T=0.5 s
T=0.354 s
2.4V
3.0V
6.2V
F=27MHz
F=2.822MHz
F=2MHz
Diagnostic Procedures by Symptom
Symptom CD-DA
TOC NG
Video-CD
TOC NG (both audio and video are NG.) Blue black display.
Likely Location Fault
For TOC NG, fault in the CD servo circuit. IC701, IC702, IC703, or traverse system. Traverse system, focus servo system (IC701,IC703), supply line, clock line system control. Traverse system, tracking servo system/ CLV servo system/ traverse servo system (IC701, IC702, IC703) IC1000 IC1000 CD disc other than DV "Karaoke" soft, video CD and CD-DA.
Turntable fails to rotate.
Fails to rotate.
Turntable rotates. Audio normal Audio normal TOC OK, counter OK, but no sound
Rotates. Audio normal, Video NG. No sound, Video NG. TOC OK, counter OK, but no sound and video NG.
Troubleshooting Procedure1
CD-DA
No sound
CD-DA: Compact disc digital audio(convertional CD only with audio tracks)
Troubleshooting flowchart
Likely location of fault
Load a CD-DA disc.
Press the SELECT(
) button to start playback.
Press the STOP(
)button to stop playback.
Taverse deck. IC701, IC702 TOC display normal? (Are track No. and time displays normal?)
NO
Refer to "Troubleshooting guide" on 18.1. CD servo circuit.
YES
Press the SELECT( ) button to start playback.
Does sound dropout occur?
NO
Normal (go to procedure 2-1)
YES
Check pin 64 of IC702 or pin 26 of CN1000.
(Check) Constant low(0V) level 0V
(Check) The following waveform is observed either intermittently constantly during playback. 6 s 6 s IPFLAG 3.2V Faults is in the traverse deck or main board (servo block).
Are the following waveforms present at pins 73 and 75 of IC702 when the 1kHz, 0dB portion of the 1st track on test disc SZZP1056C played back? 1 s
NO
2.4V
IC702
YES
IC801, Q801, Q802, headphones jack, etc.
Troubleshooting Procedure2-1
Video CD
No picture or No sound
Troubleshooting flowchart
Load a video CD disc.
Likely location of fault
Press the SELECT( Connected to TV Does the menu appear on screen?
) button to start playback. Not connected to TV
NO
YES
Press the STOP( to stop playback.
)button
TOC display normaly? (Are track No. and time displays normal?)
Traverse deck. IC701, IC702
NO
YES
Press the menu(+,-) to select the menu. Press the select ( ) to start playback.
Image noise or unstable picture.
NO YES
Normal
YES
NO
Is the sound unstable?
Check the waveforms at pin 64 of IC702 or pin 6 of CN1000. (Check) The following waveform is observed either intermittently constantly during playback. 23 s 23 s 3.2V Faults is in the traverse deck or main board (servo block).
(Check) Constant low(0V) level 0V
Are the following waveforms present at pins T=0.36 s
10
10
,
24
of CN1001?
CDDATA 3.2V
NO
T=0.36 s
24
IC1000
CDSCK 3.0V
YES
Video line Procedure 2-3 Audio line Procedure 2-4
Troubleshooting Procedure2-2
Video CD blue back
No blue back
Troubleshooting flowchart
Likely location of fault
Load a video CD disc.
Press the SELECT(
) button to start playback.
Press the STOP(
)button to stop playback.
YES
Does blue-back screen appear? Normal
NO
Is the following waveform present at pin 2 of CN1000? T=63.5 s
0.5V T=16.7 s
YES
Faults is in the main board (video output block)
0.5V
NO
IC1000
Troubleshooting Procedure2-3
Video portion of video CD No picture
Likely location of fault: IC1000
Troubleshooting Procedure2-4
Audio portion of video CD
No sound
Troubleshooting flowchart
Audio signal line
Likely location of fault
Is the following waveform present at pin 110 of IC1000? T=0.5 s
NO
6.2V
IC1000
YES
IC702