Sony CDP-CX255 / CDP-CX70ES / CDP-CX88ES Service Manual ▷ View online
— 25 —
MAGNET ASSY ALIGNMENT
Cam
(1) Rotate the cam and adjust to the posi-
tion shown in the figure.
Cam
Adjustment
screw
screw
Magnet assy
B
A
Disc
Magnet holder
Magnet assy
Adjustment
screw
screw
Adjustment
screw
screw
(2) Rotate the adjustment screw until A=B or between
A:B=2:1 and 1:2
(3) Apply suitable locking compaund to the part after adjusting.
1234
1234
1234
— 26 —
SECTION 6
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
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.
checks.
S-Curve Check
Procedure :
1. Connect oscilloscope to test point TP (FE1) on BD (TEXT)
1. Connect oscilloscope to test point TP (FE1) on BD (TEXT)
board.
2. Connect test point TP301 (ADJ) on MAIN board to ground with
lead wire.
3. Turn POWER switch on to set the ADJ mode.
4. Put disc (YEDS-18) in and playback.
4. Put disc (YEDS-18) in and playback.
Press the CHECK button.
5. Check the oscilloscope waveform (S-curve) is symmetrical be-
tween A and B. And confirm peak to peak level within 3±1 Vp-p.
S-curve waveform
oscilloscope
TP (FE1)
TP (VC)
TP (VC)
BD (TEXT) board
symmetry
within 3 ± 1 Vp-p
A
B
6. After check, remove the lead wire connected in step 2.
Note : • Try to measure several times to make sure than the ratio of
Note : • Try to measure several times to make sure than the ratio of
A : B or B : A is more than 10 : 7.
• Take sweep time as long as possible and light up the bright-
ness to obtain best waveform.
RF Level Check
Procedure :
1. Connect oscilloscope to test point TP (RF) on BD (TEXT) board.
2. Turn POWER switch on.
3. Put disc (YEDS-18) in to play the number five track.
4. Confirm that oscilloscope waveform is clear and check RF sig-
1. Connect oscilloscope to test point TP (RF) on BD (TEXT) board.
2. Turn POWER switch on.
3. Put disc (YEDS-18) in to play the number five track.
4. Confirm that oscilloscope waveform is clear and check RF sig-
nal level is correct or not.
TP (RF)
TP (VC)
TP (VC)
oscilloscope
BD (TEXT) board
Note: A clear RF signal waveform means that the shape “
◊
” can
be clearly distinguished at the center of the waveform.
RF signal waveform
level : 1.2 Vp-p
VOLT/DIV : 200mV
TIME/DIV : 500ns
TIME/DIV : 500ns
+0.25
–0.20
–0.20
E-F Balance Check
Procedure :
1. Connect oscilloscpe to test point TP (TE) on BD (TEXT) board.
2. Connect the test point TP301 (ADJ) on MAIN board to the
1. Connect oscilloscpe to test point TP (TE) on BD (TEXT) board.
2. Connect the test point TP301 (ADJ) on MAIN board to the
ground with a lead wire.
3. Turn the POWER switch on to set the ADJ mode.
4. Put disc (YEDS-18) in to play the number five track.
5. Press the “GROUP 3” button. (The tracking servo and the sled-
4. Put disc (YEDS-18) in to play the number five track.
5. Press the “GROUP 3” button. (The tracking servo and the sled-
ding servo are turned OFF.)
6. Check the level B of the oscilliscope's waveform and the A (DC
voltage) of the center of the Traverse waveform.
Confirm the following :
A/B x 100 = less than ± 22%
Confirm the following :
A/B x 100 = less than ± 22%
Traverse waveform
Center of the waveform
B
level : 1.3 ± 0.6 Vp-p
0V
7. Press the “GROUP 8” button. (The tracking servo and sledding
servo are turned ON.) Confirm the C (DC voltage) is almost
equal to the A (DC voltage) is step 6.
equal to the A (DC voltage) is step 6.
Traverse waveform
8. Disconnect the lead wire of TP301 (ADJ) connected in step 1.
A (DC voltage)
oscilloscope
TP (TE)
TP (VC)
TP (VC)
BD (TEXT) board
Tracking servo
Sledding servo
OFF
Tracking servo
Sledding servo
ON
0V
C (DC
voltage)
voltage)
— 27 —
— 28 —
RF PLL Free-run Frequenc
y Chec
k
Pr
ocedur
ocedur
e :
1.
Connect fr
Connect fr
equenc
y counter to test point
TP (PLCK) with lead
wire.
frequency counter
TP (PLCK)
BD (TEXT) board
2.
T
T
u
rn PO
WER s
witch on.
3.
Put the disc (YEDS-18) in to play the number five track.
Put the disc (YEDS-18) in to play the number five track.
Confirm that reading on frequency counter is 4.3218MHz.
Note:
The R308 mounted on the MAIN board has changed to
R
V301.
T
he set w
hic
h is c
h is c
hanged into R
V301 needs to ad-
just a disc sensor
.
Disc Sensor Adjustment
Perform this adjustment after completing all adjustments of the
mechanism section.
If not performed accura
tely
, the pr
esence of the disc ma
y not be
detected properly
.
Connection 1:
CN306 of MAIN board
T1 :
Pin
1
(T
. SENS 1)
. SENS 1)
T2 :
Pin
2
(T
. SENS 2)
. SENS 2)
D0 :
Pin
4
(D
. SENS)
. SENS)
oscilloscope
1 k
Ω
T1
T2
D0
A
B
W
a
a
v
ef
orm 1:
Connection 2:
CN305 of MAIN board
T1 :
Pin
1
(T
. SENS 1)
. SENS 1)
T2 :
Pin
2
(T
. SENS 2)
. SENS 2)
D1 :
Pin
4
(D
. SENS)
. SENS)
oscilloscope
W
a
a
v
ef
orm 2
Z
XY
T1
T2
D1
Pr
ocedur
ocedur
e:
1.
Connect the oscilloscope to Pins
Connect the oscilloscope to Pins
1
,
2
, and
,
2
, and
4
of CN306 of
of CN306 of
the MAIN boar
d
. Also connect a 1 k
Ω
r
esistor to Pin
4
a
a
t the
same time. (Connection 1)
2.
Chec
Chec
k that no discs ar
e loaded in the unit,
and press the PO
WER
b
utton w
hile pressing the INPUT b
utton.
3.
The rotary table will continue rotating in the clockwise direc-
The rotary table will continue rotating in the clockwise direc-
tion.
4.
Observe the waveform at that time on the oscilloscope.
Observe the waveform at that time on the oscilloscope.
5.
Loosen the scre
Loosen the scre
w
secur
ing the LUMINOUS board slightl
y.
6.
Slide the LUMINOUS board to the left and right so that the
Slide the LUMINOUS board to the left and right so that the
peak of the D0 waveform is at the center between the descend-
ing point of the
T1 w
av
eform and ascending point of the
T2
w
av
eform. (W
av
eform 1)
After adjusting, appl
y loc
king com-
pound.
LUMINOUS board
7. Disconnect the resistor connected to Pin
4
of CN306 of the
of CN306 of the
MAIN board. (Connection 2)
8. Observ
e the wa
v
eform on the oscilloscope
. (W
av
eform 2)
9.
Adjust R
Adjust R
V301 of the MAIN boar
d so that the w
av
eform on the
oscilloscope satisf
ies the f
ollo
wing adjustment v
alue.
10.
After the adjustment, load a disc only in slit 1, close the front
co
v
v
er
, and pr
ess the PO
WER b
utton to tur
n of
f the po
wer
.
1
1
.
Press the POWER button while pressing the ENTER button to
turn on the po
wer
.
12. If the rotary table makes one round, and “YES” is displayed on
the fluorescent indicator tube after it stops, it means that the
adjustment has been performed pr
operly
.
Adjustment v
alue:
At the shoulder part of w
av
eform D1,
T1 becomes H and
T2 be-
comes L, and a
t the same time
, the
Y width must not be smaller
than 1/4 of the Z width.
In order to sa
tisfy this v
alue mor
e easil
y,
adjust so tha
t X=Y a
p
-
pro
ximately and observ
ximately and observ
e the de
via
tion of the w
tion of the w
av
ef
o
rm.
Adjustment Location:
[ BD (TEXT) BO
ARD ]
— Side B —
TP (FE1)
TP (RF)
TP
(TE)
TP (VC)
IC103
TP
(PLCK)
IC101
[MAIN BO
ARD]
— Component Side —
TP302
AF
ADJ
ADJ
IC201
CN302
CN303
CN301
R
V301
CN306
TP301
ADJ
R324
— 29 —
— 30 —
SECTION 7
DIAGRAMS
7-1. CIRCUIT BOARDS LOCATION
JACK board
JOG board
DOOR SW board
T. MOTOR board
DISP board
ILLUMINATION board
T. SENS board
D. SENS (RAY CATCHER) board
MAIN board
BD (TEXT) board
L. SW board
L. MOTOR board
NOTE
•
: parts extracted from the component side.
•
: parts extracted from the conductor side.
•
®
: Through hole.
•
: Pattern from the side which enable seeing.
(The other layer's patterns are not indicated.)
NOTE
• All capacitors are in
µ
F unless otherwise noted. pF :
µµ
F 50WV
or less are not indicated except for electrolytics and tantalums.
• All resistors are in
Ω
and 1/4W or less unless otherwise speci-
fied.
•
¢
: internal component.
•
: panel designation.
Note:
The components identi-
fied by mark
The components identi-
fied by mark
!
or dotted
line with mark
!
are criti-
cal for safety.
Replace only with part
number specified.
Replace only with part
number specified.
Note:
Les composants identifiés par
une marque
Les composants identifiés par
une marque
!
sont critiques
pour la sécurité.
Ne les remplacer que par une
pièce portant le numéro spécifié.
Ne les remplacer que par une
pièce portant le numéro spécifié.
•
B+
: B+ Line
•
B–
: B– Line
•
: adjustment for repair.
• Voltage and waveforms are dc with respect to ground under no-
signal conditions.
no mark : STOP
no mark : STOP
• Voltages are taken with a VOM (Input impedance 10M
Ω
).
Voltage variations may be noted due to normal production tol-
erances.
erances.
• Waveforms are taken with a oscilloscope.
Voltage variations may be noted due to normal production tol-
erances.
erances.
• Circled numbers refer to waveforms.
• Signal path.
• Signal path.
: CD
: CD (digital)
: CD (digital)
IC101
@¶
TE (PLAY)
• Waveforms
1
1.4Vp-p
IC101
#§
RFAC (PLAY)
2
2.5V
APPROX 400mVp-p
3
IC101
@ª
FE (PLAY)
2.5V
APPROX 200mVp-p
4
5.2Vp-p
7.5µsec
IC101
(§
MDP (PLAY)
• BD Section
IC301
#™
XTAL
• Waveforms
• MAIN Section
1
2
23µsec
4.9Vp-p
0.48µsec
3
5.644MHz
5.1Vp-p
4
4.6Vp-p
33.869MHz
5
22.577MHz
6
4.8Vp-p
10MHz
5.5Vp-p
IC303
#ª
LRCKI
IC303
#•
BCKI
IC303
$¶
128FSO
IC303
$ª
INVO1
IC303
9
XOUT
5.2Vp-p
D. SENS (LUMINOUS) board
Click on the first or last page to see other CDP-CX255 / CDP-CX70ES / CDP-CX88ES service manuals if exist.