– 8 –
Focus Bias Check
Condition :
• Hold the set in horizontal state.
Procedure :
[MAIN BOARD] (Side B)
1. Set the equipment to service mode stop state (See page 7).
2. Connect the oscilloscope between TP513 (RFO) and TP533 (VC)
on the MAIN board.
3. Move the optical pick-up by Pressing the
+
and
=
keys.
4 Put the disc (YEDS-18).
5. Press the
^
key.
From focus searching, focus is turned ON while entering
CLV drawing-in mode. Tracking and sled are turned OFF.
6. Press the PLAY MODE key. (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 cen-
ter of the waveform can be clearly distinguished.
•
RF Signal Reference Waveform (eye pattern)
To watch the eye pattern, set the oscilloscope to AC range and
increase the vertical sensitivity of the oscilloscope for easy watch-
ing.
8. Stop removing of the motor by pressing the
p
key.
9. After the completion of adjustment, reset service mode.
(See page 7 )
SECTION 5
ADJUSTMENTS
( )
CD SECTION
Precautions for Adjustment
1. Before beginning adjustment, set the equipment to service mode.
After the completion of adjustment, be sure to reset the service
mode.
For more information, see “Service Mode (service program)”
on page 7.
2. Perform adjustments in the order given.
3. Use the disc (YEDS-18. Part No. 3-702-101-01) unless other-
wise indicated.
4. Power supply voltage requirement : DC 4.5 V
HOLD switch
: OFF
VOLUME
: Minimum
SOUND switch : NORM
AVLS switch
: OFF
Before Beginning Adjustment
Set the equipment to service mode (See page 7) and check the fol-
lowing.
If there in an error, repair the equipment.
• Checking of the sled motor
1. Open the upper panel.
2. Press the
+
and
=
keys and check that the optical pick-up
can move smoothly without sluggishness or abnormal noise in
innermost periphery
n
outermost periphery
n
innermost pe-
riphery.
+
: The optical pick-up moves outwardly
=
: The optical pick-up moves inwardly
• Checking of focus searching
1. Open the upper panel.
2. Press the
^
key. (Focus searching operation is activated con-
tinuously).
3. Check the object lens of the optical pick-up for smooth up/down
motion without sluggishness or abnormal noise.
4. Press the
p
key.
Check that focus searching operation is deactivated. If not, again
press the
p
key slightly longer.
RF level
0.8 – 1.2 Vp-p
1
5
8
17
20
24
25
32 30
TP102
TP202
TP302
TP306
TP540
TP508
IC501
TP503
TP533
(VC)
TP523
TP547
TP513
(RFO)
TP502
TP504
TP506
TP507
TP534
TP511
TP512
TP509
TP514
(TEO)
TP515
TP521
TP522
C105
C108
C205
C208
C501
Q201
Q101
D105
D804
D205
FB201
FB101
FB302
R521
R512
R519
R501
807
0
4
8
R549
R517
R504
R503
R502
C514
C599
C598
C503
C505
C510
C513
C504
C512
11
C520
L502
Q501 C525
C517
R505
C506
L508
C571
TP513 (RFO)
TP533
(VC)
2 k
Ω
oscilloscope
(AC range)
