Sony CMT-EP303 / HCD-EP303 Service Manual ▷ View online
2
HCD-EP303
TABLE OF CONTENTS
Tuner section
FM stereo, FM/AM superheterodyne tuner
FM stereo, FM/AM superheterodyne tuner
FM tuner section
Tuning range
87.5 - 108.0 MHz
Antenna
FM lead antenna
Intermediate frequency
10.7 MHz
AM tuner section
Tuning range
Pan-American model:
Pan-American model:
530 - 1 710 kHz
(with the interval set at
10 kHz)
531 - 1 602 kHz
(with the interval set at
9 kHz)
(with the interval set at
10 kHz)
531 - 1 602 kHz
(with the interval set at
9 kHz)
European model:
531 -1 602 kHz
(with the interval set at
9 kHz)
(with the interval set at
9 kHz)
Other models:
531 - 1 602 kHz
(with the interval set at
9 kHz)
530 - 1 710 kHz
(with the interval set at
10 kHz)
(with the interval set at
9 kHz)
530 - 1 710 kHz
(with the interval set at
10 kHz)
Antenna
Built-in ferrite bar antenna
Intermediate frequency
450 kHz
General
Power requirements
North American model:
Power requirements
North American model:
120 V AC, 60 Hz
European model:
230 V AC, 50/60 Hz
Australian model:
230 V AC, 50/60 Hz
Mexican model:
120 V AC, 60 Hz
Argentine model:
220 - 230 V AC, 50/60 Hz
Other models:
230 V AC, 50/60 Hz
Power consumption
U.S.A. model:
U.S.A. model:
25 W
Canadian model:
25 W
European model:
30 W
0.5 W (in the standby
mode)
0.5 W (in the standby
mode)
Other models:
30 W
Dimensions (w/h/d):
Approx. 145
× 240 × 252 mm
Mass:
Approx. 2.9 kg
Design and specifications are subject to change
without notice.
without notice.
1. SERVICING NOTES
······················································ 4
2. GENERAL
·········································································· 5
3. DISASSEMBLY
································································ 7
3-1. Front Panel Section ······················································· 7
3-2. MAIN Board ································································· 8
3-3. Tape Mechanism Deck (TCM125-2) ··························· 8
3-4. POWER Board, Power Transformer ···························· 9
3-5. DISPLAY Board, HEADPHONE Board ····················· 9
3-6. CD Cabinet Section ··················································· 10
3-7. CD Mechanism Deck (CS-21SC-1280) ····················· 10
3-8. Cassette Lid ······························································· 11
3-2. MAIN Board ································································· 8
3-3. Tape Mechanism Deck (TCM125-2) ··························· 8
3-4. POWER Board, Power Transformer ···························· 9
3-5. DISPLAY Board, HEADPHONE Board ····················· 9
3-6. CD Cabinet Section ··················································· 10
3-7. CD Mechanism Deck (CS-21SC-1280) ····················· 10
3-8. Cassette Lid ······························································· 11
4. MECHANICAL ADJUSTMENTS
····························· 12
5. ELECTRICAL ADJUSTMENTS
······························· 12
6. DIAGRAMS
······································································ 16
6-1. Circuit Boards Location ·············································· 16
6-2. Block Diagrams ·························································· 18
6-3. Printed Wiring Board MAIN Section ························ 21
6-4. Schematic Diagram MIAN Section (1/2) ·················· 22
6-5. Schematic Diagram MIAN Section (2/2) ·················· 23
6-6. Printed Wiring Board CASSETTE Section ··············· 24
6-7. Schematic Diagram CASSETTE Section ·················· 24
6-8. Printed Wiring Board DISPLAY Section ·················· 25
6-9. Schematic Diagram DISPLAY Section ····················· 26
6-10. Printed Wiring Board POWER Section ····················· 27
6-11. Schematic Diagram POWER Section ························ 28
6-12. IC Pin Function Description ······································· 31
6-2. Block Diagrams ·························································· 18
6-3. Printed Wiring Board MAIN Section ························ 21
6-4. Schematic Diagram MIAN Section (1/2) ·················· 22
6-5. Schematic Diagram MIAN Section (2/2) ·················· 23
6-6. Printed Wiring Board CASSETTE Section ··············· 24
6-7. Schematic Diagram CASSETTE Section ·················· 24
6-8. Printed Wiring Board DISPLAY Section ·················· 25
6-9. Schematic Diagram DISPLAY Section ····················· 26
6-10. Printed Wiring Board POWER Section ····················· 27
6-11. Schematic Diagram POWER Section ························ 28
6-12. IC Pin Function Description ······································· 31
7. EXPLODED VIEWS
······················································ 32
7-1. Cabinet Section ··························································· 32
7-2. Front Panel Section -1 ················································ 33
7-3. Front Panel Section -2 ················································ 34
7-4. CD Cabinet Section ···················································· 35
7-2. Front Panel Section -1 ················································ 33
7-3. Front Panel Section -2 ················································ 34
7-4. CD Cabinet Section ···················································· 35
8. ELECTRICAL PARTS LIST
······································· 36
3
To Exposed Metal
Parts on Set
0.15
µ
F
1.5 k
Ω
AC
Voltmeter
(0.75 V)
Voltmeter
(0.75 V)
Earth Ground
Fig. A. Using an AC voltmeter to check AC leakage.
This appliance is classified as a CLASS 1 LASER product. The
CLASS 1 LASER PRODUCT MARKING is located on the rear
exterior.
CLASS 1 LASER PRODUCT MARKING is located on the rear
exterior.
The following caution label is located inside the unit.
CAUTION
Use of controls or adjustments or performance of procedures
other than those specified herein may result in hazardous radiation
exposure.
other than those specified herein may result in hazardous radiation
exposure.
HCD-EP303
SAFETY-RELATED COMPONENT WARNING!!
COMPONENTS IDENTIFIED BY MARK
0
OR DOTTED LINE WITH
MARK
0
ON THE SCHEMATIC DIAGRAMS AND IN THE PARTS
LIST ARE CRITICAL TO SAFE OPERATION. REPLACE THESE
COMPONENTS WITH SONY PARTS WHOSE PART NUMBERS
APPEAR AS SHOWN IN THIS MANUAL OR IN SUPPLEMENTS
PUBLISHED BY SONY.
COMPONENTS WITH SONY PARTS WHOSE PART NUMBERS
APPEAR AS SHOWN IN THIS MANUAL OR IN SUPPLEMENTS
PUBLISHED BY SONY.
ATTENTION AU COMPOSANT AYANT RAPPORT
À LA SÉCURITÉ!
LES COMPOSANTS IDENTIFÉS PAR UNE MARQUE
0
SUR LES
DIAGRAMMES SCHÉMATIQUES ET LA LISTE DES PIÈCES SONT
CRITIQUES POUR LA SÉCURITÉ DE FONCTIONNEMENT. NE
REMPLACER CES COMPOSANTS QUE PAR DES PIÈSES SONY
DONT LES NUMÉROS SONT DONNÉS DANS CE MANUEL OU
DANS LES SUPPÉMENTS PUBLIÉS PAR SONY.
CRITIQUES POUR LA SÉCURITÉ DE FONCTIONNEMENT. NE
REMPLACER CES COMPOSANTS QUE PAR DES PIÈSES SONY
DONT LES NUMÉROS SONT DONNÉS DANS CE MANUEL OU
DANS LES SUPPÉMENTS PUBLIÉS PAR SONY.
Notes on chip component replacement
• Never reuse a disconnected chip component.
• Notice that the minus side of a tantalum capacitor may be
• Notice that the minus side of a tantalum capacitor may be
damaged by heat.
Flexible Circuit Board Repairing
• Keep the temperature of soldering iron around 270˚C
during repairing.
• Do not touch the soldering iron on the same conductor of the
circuit board (within 3 times).
• Be careful not to apply force on the conductor when soldering
or unsoldering.
SAFETY CHECK-OUT
After correcting the original service problem, perform the following
safety checks before releasing the set to the customer:
Check the antenna terminals, metal trim, “metallized” knobs,
screws, and all other exposed metal parts for AC leakage. Check
leakage as described below.
safety checks before releasing the set to the customer:
Check the antenna terminals, metal trim, “metallized” knobs,
screws, and all other exposed metal parts for AC leakage. Check
leakage as described below.
LEAKAGE TEST
The AC leakage from any exposed metal part to earth ground and
from all exposed metal parts to any exposed metal part having a
return to chassis, must not exceed 0.5 mA (500 microamperes).
Leakage current can be measured by any one of three methods.
from all exposed metal parts to any exposed metal part having a
return to chassis, must not exceed 0.5 mA (500 microamperes).
Leakage current can be measured by any one of three methods.
1.
A commercial leakage tester, such as the Simpson 229 or RCA
WT-540A. Follow the manufacturers’ instructions to use these
instruments.
WT-540A. Follow the manufacturers’ instructions to use these
instruments.
2.
A battery-operated AC milliammeter. The Data Precision 245
digital multimeter is suitable for this job.
digital multimeter is suitable for this job.
3.
Measuring the voltage drop across a resistor by means of a
VOM or battery-operated AC voltmeter. The “limit” indication
is 0.75 V, so analog meters must have an accurate low-voltage
scale. The Simpson 250 and Sanwa SH-63Trd are examples
of a passive VOM that is suitable. Nearly all battery operated
digital multimeters that have a 2V AC range are suitable. (See
Fig. A)
VOM or battery-operated AC voltmeter. The “limit” indication
is 0.75 V, so analog meters must have an accurate low-voltage
scale. The Simpson 250 and Sanwa SH-63Trd are examples
of a passive VOM that is suitable. Nearly all battery operated
digital multimeters that have a 2V AC range are suitable. (See
Fig. A)
4
HCD-EP303
SECTION 1
SERVICING NOTES
• MODEL IDENTIFICATION
– Bottom View –
– Bottom View –
NOTES ON HANDLING THE OPTICAL PICK-UP
BLOCK OR BASE UNIT
BLOCK OR BASE UNIT
The laser diode in the optical pick-up block may suffer electrostatic
break-down because of the potential difference generated by the
charged electrostatic load, etc. on clothing and the human body.
During repair, pay attention to electrostatic break-down and also
use the procedure in the printed matter which is included in the
repair parts.
The flexible board is easily damaged and should be handled with
care.
break-down because of the potential difference generated by the
charged electrostatic load, etc. on clothing and the human body.
During repair, pay attention to electrostatic break-down and also
use the procedure in the printed matter which is included in the
repair parts.
The flexible board is easily damaged and should be handled with
care.
NOTES ON LASER DIODE EMISSION CHECK
The laser beam on this model is concentrated so as to be focused on
the disc reflective surface by the objective lens in the optical pick-
up block. Therefore, when checking the laser diode emission,
observe from more than 30 cm away from the objective lens.
the disc reflective surface by the objective lens in the optical pick-
up block. Therefore, when checking the laser diode emission,
observe from more than 30 cm away from the objective lens.
LASER DIODE AND FOCUS SEARCH OPERATION
CHECK
CHECK
1.
Press the ?/1 button to the power ON with no disc inserted
and press the CD button.
and press the CD button.
2.
Open the lid for CD.
3.
Turn on SW600 as following figure.
4.
Confirm the laser diode emission while observing the objecting
lens. When there is no emission, Auto Power Control circuit or
Optical Pick-up is broken.
Objective lens moves up and down five times for the focus
search.
lens. When there is no emission, Auto Power Control circuit or
Optical Pick-up is broken.
Objective lens moves up and down five times for the focus
search.
SW600
PART No.
at least 30 mm.
CASSETTE board
MAIN board
HEADPHONE
board
board
at least 30 mm
heatsink
MODEL
PART No.
AEP, UK models
4-235-972-0
<
EXCEPT AEP, UK models
4-241-498-0
<
TO PREVENT ‘TAPE OSCILLATION SOUND AT VOLUME’
MAXIMUM SETTING (W/O TAPE)
MAXIMUM SETTING (W/O TAPE)
Headphone wire dressing:
a.) Draw the wire from Main board to Headphone board along the
a.) Draw the wire from Main board to Headphone board along the
bottom side of heatsink.
b.) The wire must be kept away from the top side of Cassette board
5
HCD-EP303
SECTION 2
GENERAL
This section is extracted
from instruction manual.
from instruction manual.
Main unit
R – Z
Remote sensor q;
REPEAT
REPEAT
(8)
SHUFFLE
(8)
TAPE
(12)
TIMER indicator
(15)
TUNER
(10, 11, 13)
TUNER MEM
(10)
TUNING +/–
(10, 11)
VOLUME control
ALPHABETICAL ORDER
A – P
Cassette compartment qd (12)
CD 4 (8, 9, 13)
Display Window 5 8, 9, 10)
ENTER/PGM
CD 4 (8, 9, 13)
Display Window 5 8, 9, 10)
ENTER/PGM
8, 9, 10, 14)
MEGA BASS
(14)
MUSIC MENU 9 (14)
PHONES jack
PRESET +/–
PHONES jack
PRESET +/–
(10, 11)
BUTTON DESCRIPTIONS
@/1 (power)
(6)
CD
.m /M> (go back/go
forward)
(8, 9)
u (play/pause)
(8, 9)
Z PUSH OPEN/CLOSE
(8)
x (stop)
(8)
TAPE
M (fast forward)
(12)
X (pause)
(12, 13)
N (play)
(12)
z (recording)
(13)
m (rewind)
(12)
xZ (stop/eject)
(12, 13)
w;
8
ws
qs
2
wa
3
1
6
w;
wd
qa
wh
wd
wf
7
wg
qh
qf
qk
ql
qj
qg
