22
RCD-W2000ES
SECTION 5
ELECTRICAL ADJUSTMENTS
Note :
1. CD Block is basically designed to operate without adjustment.
Therefore, check each item in order given.
2. Use YEDS-18 disc (3-702-101-01) unless otherwise indicated.
3. Use an oscilloscope with more than 10M
Ω
impedance.
4. Clean the object lens by an applicator with neutral detergent
when the signal level is low than specified value with the
following checks.
S Curve Check
Connection :
Procedure :
1. Connect an oscilloscope to test point TP4 (FE) and TP7 (VC)
on the BD board.
2. Turn the power on.
3. Load the disc (YEDS-18).
4. Enter the test mode, select the BU Test and press the
l
AMS
L
(DECK B) knob to display “bdt S CURVE”.
5. Press the
l
AMS
L
(DECK B) knob. “LD AL” is
displayed and playback starts automatically.
6. Check the oscilloscope waveform (S-curve) is symmetrical
between A and B.
7. Press the MENU/NO button to stop playback.
8. Exit from the test mode.
(Refer to the TEST MODE Section)
Note:
Try to measure several times to make sure than the ratio of A
: B or B : A is more than 10 : 7.
Checking Location :
BD board (Side B)(See page 23)
RF Level Check
Connection :
Procedure :
1. Connect an oscilloscope to TP8 (RFAC) and TP7 (VC).
2. Turn the power on.
3. Load the disc (YEDS-18) and playback the number five track.
4. Confirm that oscilloscope waveform is clear and check RF signal
level is correct or not.
CD SECTION
(DECK A)
Note:
A clear RF signal waveform means that the shape “
◊
” can be
clearly distinguished at the center of the waveform.
Checking Location :
BD board (Side B)(See page 23)
E-F Balance Adjustment
Connection :
Procedure:
1.
Connect an oscilloscope to TP2 (TE) and TP7 (VC) on the
BD board.
2.
Turn the power on.
3.
Load the disc (YEDS-18) and playback the number five track.
4.
Enter the Service Mode. (see page 19) Press the INPUT
button until “TRV ON” is displayed. (The tracking servo and
the sledding servo are turned off.)
5.
Check the level B of the oscilloscope waveform. Rotate the
RV101 on the BD board and adjust so that the A (DC voltage)
of the center of the traverse waveform becomes 0 volt.
6.
Press the INPUT button until “TRV OFF” is displayed and
the tracking servo and the sledding servo are turned on.
Confirm that the C (DC voltage) is almost equal to the A (DC
voltage).
7.
Exit from the test mode. (see page 19)
Checking Location :
BD board (Side B)(See page 23)
Adjustment at Replacement of CD Base Unit
(BU-30BBD61M)
Perform the E-F Balance Adjustment at replacement of CD base
unit (BU-30BBD61M).
VOLT/DIV : 200mV
TIME/DIV : 500ns
level : 1.1
±
0.3Vp-p
Traverse Waveform
0V
B
level: 1.1
±
0.5 Vp-p
Center of
the waveform
A (DC
voltage)
+
–
BD board
TP4 (FE)
TP7 (VC)
oscilloscope
(DC range)
A
B
symmetry
+
–
BD board
TP8 (RFAC)
TP7 (VC)
oscilloscope
(AC range)
+
–
BD board
TP2 (TE)
TP7 (VC)
oscilloscope
(DC range)
Traverse Waveform
0V
Tracking servo
Sled servo
ON
C (DC
voltage)
Tracking servo
Sled servo
OFF
