Sony D-V55, Руководство по обслуживанию

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5-4. Focus Bias Check
Condition:
• Hold the set in horizontal state.
Connection:
4 3
2
1
5
6
4 3
2
1
5
6
1
5
10 11
20
BC E
B
C
E
B
C
E
BCE
BCE
R532
C525
C526
R751
C518
D501
C516
R544
L506
R518
IC501
R520
R531
R522
R542
R514
C530
C507
R515
R513
R525
C522
C529
R512
R516
R543
C502
Q504
R510
Q506
Q502
R509
C509
R506
R554
R528
R507
R511
R521
R519
R517
R526
Q501
C519
R523
Q503
Q507
C508
R527
TP512
TP520
TP534
TP540
TP537
TP531
TP536
TP524
TP535(RFO)
TP522
(FE)
TP523 (TE)
TP508
(VC)
TP521
TP752
TP810
TP809
TP530
TP525
15
TP535 (RFO)
2k
Ω
oscillscope
(AC range)
TP508 (VC)
Checking Method:
1. Connect the oscilloscope to TP535 (RFO) and TP508 (VC)
on the MAIN board.
2. Set the equipment to service mode stop state. (See page 9.)
3. Press the
fl
key once.
4. Move the optical pick-up to the center by pressing the
±
and
≠
keys.
5. Put the disc (YEDS-18).
6. Press the
fl
key four times.
From focus searching, focus is turned ON while
entering CLV drawing-in mode. Both tracking and
sled are turned ON.
7. Check the oscilloscope waveform is as shown below.
A good eye pattern means that the diamond shape (
≈
) in the
center of the waveform can be clearly distinguished.
RF SIGNAL REFERENCE WAVEFORM (EYE PATTERN)
VOLT/DIV : 200 mV (With the 10:1 probe in use)
TIME/DIV : 500 ns
To watch the eye pattern, set the oscilloscope to AC range and in-
crease the vertical sensitivity of the oscilloscope for easy watching.
MAIN board (Side B)
8. Stop revolving of the disc motor by pressing the
π
key.
9. After the completion of check, reset service mode.
(See page 9.)
RF level
0.5 – 0.9 Vp-p