JVC JX-S555, Руководство по обслуживанию

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(No. 70251) 13
JX-S555(J)
Servicing Guidelines
1. Reference input signals
Video signals
V
→
Full-field color bar (white 100%), 1.0 Vp-p
Y
→
1.0 Vp-p (with sync)
C
→
Burst level 0.286 Vp-p, chroma only
Audio signal
1 kHz, -10 dBV sine wave
2. YES
→
Normal
NO
→
The normal voltage and waveform are not output.
1. Power cannot be
turned ON.
2. Display LED
lighting failure.
C903: /- leads
1
Approx. 164 V DC NO
YES
Check power cord and C901.
If the fuse is blown, check Q901,
T901, D901 and their surroundings.
Go to check
2
.
D906: Cathode
D907: Anode
2
+9.5 V DC
–9.8 V DC
NO
YES
NO R Check voltage at IC902 and
surroundings.PC901 and IC902
may be defective.
Go to check
3
.
Q904: Emitter,
Q905: Emitter,
Q906: Emitter,
IC904: Pin 2
3
–6 V DC
+6 V DC
+5 V DC
+9 V DC
NO
YES
IC901, IC903, IC904 or Q904 to
Q906 defective.
Check CN1,. CN3 and wires.
CN3: Pins 3 to 7
4
0 or +5 V DC NO
YES
IC2 defective.
Q701 to Q706 or wire is defective.
3. Switch operation
failure.
CN3: Pins 8 to 14 0 or +5 V DC NO
YES
IC2 defective.
CN701, tack switch or wire defective.
5
4. S/V switching
failure
IC101: Pins 7, 14, 21 and 28 0 V when S-Video plug is inserted.
+5 V when S-Video plug is not
inserted.
NO
YES
PJ107 to PJ110 defective.
Check IC101 and the surroundings.
6
5. Remote control
malfunction
IC2: Pin 55 + 5 V DC at remote control
code (See TM.)
NO
YES
IC701, CN1, CN702 or wire defective.
IC2 defective.
7
6. The composite
video inputs at
CH1 and CH2
are not displayed.
A
Q135: Emitter NO
YES
Go to check
B
.
Check Q152, Q161, Q170 and
their surroundings.
7. The composite
video inputs at
CH1 and CH2
are not output at
the Monitor
output.
Q129: Emitter NO
YES
Go to check
9
.
Check IC106, output buffer and their
surroundings.
Q107: emitter NO
YES
Check IC101 and surroundings.
Check IC103 and their surroundings.
8
9
Symptom Check Points Normal Voltage/Waveform Check Results and Failures
2.0 Vp-p
Q115: Emitter NO
YES
Check IC101 and surroundings.
Check IC103 and their surroundings.
B
2.0 Vp-p
2.0 Vp-p
2.0 Vp-p