Sony CMT-EX1 / HCD-EX1 Service Manual ▷ View online
13
Note:
1. CD Block is basically constructed 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 the oscilloscope to test points TP (FE) and TP (VC).
2. Connect TP (FEI) and TP (VC) of the MAIN board with lead
1. Connect the oscilloscope to test points TP (FE) and TP (VC).
2. Connect TP (FEI) and TP (VC) of the MAIN board with lead
wires.
3. Press the
1/u button to turn the set ON.
4. Press the
^ button, load and eject the disc (YEDS-18) to
perform focus search.
5. Check the symmetry and peak to peak level of the oscilloscope
waveform (S curve) at this time.
S-curve waveform
6. After check, remove the lead wire connected in step 2.
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.
Checking Location : MAIN board
RF Level Check
Procedure :
1. Connect oscilloscope to test point TP (RF) and TP (VC) on MAIN
1. Connect oscilloscope to test point TP (RF) and TP (VC) on MAIN
board.
2. Press the
1/u button to turn the set ON.
3. Put disc (YEDS-18) in and playback 5track.
4. Confirm that oscilloscope waveform is clear and check RF sig-
4. Confirm that oscilloscope waveform is clear and check RF sig-
nal level is correct or not.
oscilloscope
MAIN board
TP (FE)
TP (VC)
TP (VC)
+
–
–
symmetry
A
B
Within 3.8
±
1 Vp-p
oscilloscope
MAIN board
TP (RF)
TP (VC)
TP (VC)
+
–
–
VOLT/DIV : 200mV
TIME/DIV : 500ns
TIME/DIV : 500ns
level : 1.2
±
0.2 Vp-p
0V
Center of the waveform
B
Symmetry
A (DC voitage)
level : 1.3
±
Vp-p
+0.6
–0.7
–0.7
oscilloscope
MAIN board
TP (TE)
TP (VC)
TP (VC)
+
–
–
Note:
Clear RF signal waveform means that the shape “
◊
” can be
clearly distinguished at the center of the waveform.
RF signal waveform
Checking Location : MAIN board
E-F Balance (1 Track Jump) check
Procedure:
1. Connect oscilloscope to test point TP (TE) and TP (VC) on MAIN
1. Connect oscilloscope to test point TP (TE) and TP (VC) on MAIN
board.
2. Press the
1/u button to turn the unit ON.
3. Put disc (YEDS-18) in to play the number five track.
4. Press the
4. Press the
^ button, to pause.
5. Check the level (B) of the oscilloscope's waveform and the DC
voltage (A) of the center of the Traverse waveform.
Confirm the following:
Confirm the following:
• A/B x 100 = less then ± 22 (%)
• B = 1.3 ±
• B = 1.3 ±
Vp-p
1 track jump waveform
SECTION 4
ELECTRICAL ADJUSTMENT
+0.6
–0.7
–0.7
Checking Location : MAIN board
[ MAIN BOARD ] — SIDE A —
TP
(VC)
(VC)
TP
(FEI)
(FEI)
TP
(RF)
(RF)
TP
(FE)
(FE)
TP
(TE)
(TE)
IC303
IC301
14
SECTION 5
DIAGRAMS
5-1. CIRCUIT BOARDS LOCATION
MAIN BOARD
AMP BOARD
REG BOARD
SW BOARD
POWER BOARD
PANEL BOARD
LED BOARD
LOADING BOARD
HCD-EX1
15
15
• Indication of transistor
C
These are omitted
E
B
Q
C
These are omitted
E
B
IC303
#ª
FE
1
2
3
4
5
WAVEFORMS
– MAIN (1/3) SECTION –
– MAIN (1/3) SECTION –
IC304
6
XTO
IC303
%º
RF AC
IC303
$¡
TE
IC303
@∞
MDP
3.1Vp-p
16.9MHz
1.2Vp-p
(PLAY)
2.5V
APPROX 500mVp-p (PLAY)
7.5
µ
sec
2.4Vp-p
2.5V
APPROX 200m Vp-p (PLAY)
6
7
IC701
!£
XT2
IC701
0
X2
– MAIN (3/3) SECTION –
5MHz
5.5Vp-p
32.768kHz
5Vp-p
THIS NOTE IS COMMON FOR PRINTED WIRING
BOARDS AND SCHEMATIC DIAGRAMS.
(In addition to this, the necessary note is printed
in each block.)
BOARDS AND SCHEMATIC DIAGRAMS.
(In addition to this, the necessary note is printed
in each block.)
For schematic diagrams.
Note:
• All capacitors are in µF unless otherwise noted. pF: µµF
• All capacitors are in µF unless otherwise noted. pF: µµF
50 WV or less are not indicated except for electrolytics
and tantalums.
and tantalums.
• All resistors are in
Ω
and
1
/
4
W or less unless otherwise
specified.
•
¢
: internal component.
•
2
: nonflammable resistor.
•
5
: fusible resistor.
•
C
: panel designation.
For printed wiring boards.
Note:
• X
: parts extracted from the component side.
•
®
: Through hole.
• b
: Pattern from the side which enables seeing.
(The other layers' patterns are not indicated.)
•
U
: B+ Line.
•
V
: B– Line.
•
H
: adjustment for repair.
• Voltages and waveforms are dc with respect to ground
under no-signal (detuned) conditions.
• Voltages and waveforms are dc with respect to ground in
service mode.
• Waveforms are taken with a oscilloscope.
Voltage variations may be noted due to normal produc-
tion tolerances.
no mark : STOP
tion tolerances.
no mark : STOP
• Circled numbers refer to waveforms.
• Signal path.
• Signal path.
J
: CD
c
: digital out
• Abbreviation
CND : Canadian model.
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
piéce portant le numéro
spécifié.
Ne les remplacer que par une
piéce portant le numéro
spécifié.
HCD-EX1
16
16
(Page 24)
(Page 28)
(Page 16)
(Page 22)
5-2. PRINTED WIRING BOARD – MAIN SECTION –
• See page 14 for Circuit Boards Location.
Ref. No.
Location
D139
E-4
D701
D-3
D751
D-3
D752
D-3
D753
D-3
D754
D-4
IC111
C-5
IC301
C-3
IC302
B-3
IC303
B-4
IC304
A-5
IC391
B-6
IC451
A-1
IC501
A-6
IC701
D-1
IC751
C-4
Q113
D-4
Q131
D-4
Q163
D-4
Q301
C-2
Q401
D-6
Q751
D-4
Q771
D-1
Q772
D-1
Q781
C-4
Q782
C-3
• Semiconductor
Location
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