Sony HCD-EP404 User manual

HCD-EP404
AEP Model
UK Model
SERVICE MANUAL
COMPACT DISC DECK RECEIVER
Sony Corporation
Home Audio Company
Published by Sony Engineering Corporation
9-873-940-02
2002F1600-1
© 2002.07
HCD-EP404 is the amplifler, CD
player, tape deck and tuner section in
CMT-EP404.
SPECIFICATIONS
Ver 1.1 2002. 07
CD Model Name Using Similar Mechanism HCD-EP50
SECTION CD Mechanism Type CS-21SC-1280
TAPE DECK Model Name Using Similar Mechanism NEW
SECTION Tape Transport Mechanism Type CFL4318
Amplifier section
DIN power output (rated) 6 + 6 W
(8Ωat 1 kHz, DIN)
Continuous RMS power output (reference)
8 + 8 W
(8Ωat 1 kHz, 10% THD)
Music power output (reference)
16 + 16 W
Outputs
PHONES: Accepts headphones of
(stereo mini jack) 8Ωor more
SPEAKER: Accepts impedance of 8 to
16Ω
CD player section
System Compact disc and digital
audio system
Laser Semiconductor laser
(λ =780 nm)
Emission duration:
continuous
Frequency response 20 Hz - 20 kHz (±0.5 dB)
Tape player section
Recording system 4-track 2-channel stereo
Frequency response 50 - 13 000 Hz (±3 dB),
using Sony TYPE I
cassette
Tuner section
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 531 -1 602 kHz
(with the interval set at
9 kHz)
Antenna Built-in ferrite bar antenna
Intermediate frequency 450 kHz
General
Power requirements 230 V AC, 50/60 Hz
Power consumption 38W
0.5 W (in the standby
mode)
Dimensions (w/h/d): Approx. 145 × 240 × 252 mm
Mass: 3.1 kg
Design and specifications are subject to change
without notice.

2
HCD-EP404
TABLE OF CONTENTS
This appliance is classified as a CLASS 1 LASER product. The
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
otherthanthosespecifiedhereinmayresultin hazardous radiation
exposure.
SAFETY-RELATED COMPONENTWARNING!!
COMPONENTS IDENTIFIED BY MARK 0OR DOTTED LINEWITH
MARK 0ON THE SCHEMATIC DIAGRAMS AND INTHE 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.
Notes on chip component replacement
•Never reuse a disconnected chip component.
•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.
1. SERVICING NOTES······················································ 3
2. GENERAL ·········································································· 4
3. DISASSEMBLY ································································ 6
3-1. Front Panel Section······················································· 6
3-2. MAIN Board ································································· 7
3-3. Tape Mechanism Deck (CFL4318)······························· 7
3-4. POWER Board, Power Transformer····························· 8
3-5. DISPLAY Board, HEADPHONE Board ······················ 8
3-6. CD Cabinet Section ······················································ 9
3-7. CD Mechanism Deck (CS-21SC-1280)························ 9
3-8. Cassette Lid ································································ 10
4. MECHANICAL ADJUSTMENTS ····························· 11
5. ELECTRICAL ADJUSTMENTS ······························· 11
6. DIAGRAMS······································································ 15
6-1. Circuit Boards Location·············································· 15
6-2. Block Diagrams ·························································· 16
TUNER/TAPE DECK Section ··································· 16
AMP Section······························································· 17
DISPLAY/POWER Section ········································ 18
6-3. Printed Wiring Board MAIN Section ························ 19
6-4. Schematic Diagram MAIN Section (1/3) ·················· 20
6-5. Schematic Diagram MAIN Section (2/3) ·················· 21
6-6. Schematic Diagram MAIN Section (3/3) ·················· 22
6-7. Printed Wiring Board PANEL Section ······················ 23
6-8. Schematic Diagram PANEL Section ························· 24
6-9. Printed Wiring Board POWER Section ····················· 25
6-10. Schematic Diagram POWER Section························ 26
6-12. IC Pin Function Description ······································· 29
7. EXPLODED VIEWS ······················································ 31
7-1. Cabinet Section ··························································· 31
7-2. Front Panel Section -1 ················································ 32
7-3. Front Panel Section -2 ················································ 33
7-4. CD Cabinet Section ···················································· 34
8. ELECTRICAL PARTS LIST ······································· 35
Ver 1.1 2002.07

3
HCD-EP404
SECTION 1
SERVICING NOTES
NOTES ON HANDLING THE OPTICAL PICK-UP
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.
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.
SW600
LASER DIODE AND FOCUS SEARCH OPERATION
CHECK
1. Press the ?/1 button to the power ON with no disc inserted
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.

4
HCD-EP404 SECTION 2
GENERAL This section is extracted
from instruction manual.
Main unit
P – Z
PHONES jack qk
PLAY MODE qj (8, 9)
PRESET +/– qd (11, 13)
Remote sensor 0
TAPE 3(14)
TIMER indicator 1(16, 18)
TUNER 6(10, 11, 12, 15)
TUNER MEM qh (10, 11)
TUNING +/– qa (10, 11, 12, 13)
VOLUME control qs
ALPHABETICAL ORDER
A – M
Cassette compartment qg (14)
CD 4(8, 9, 15)
DISPLAY 2(12, 19)
Display Window 5(8, 9, 10,
11)
ENTER qh (7, 9, 10, 11, 13)
MEGA BASS 8(17)
MUSIC MENU 9(17)
BUTTON DESCRIPTIONS
@/1 (power) wd (7, 16, 18)
CD
.m(go back) qa (8, 9, 14)
M> (go forward) qa (8, 9,
14)
N(play) w; (8, 9)
X(pause) ws (8)
ZPUSH OPEN/CLOSE 7(8)
x(stop) ql (8, 9)
TAPE
M>(fast forward) qa (14)
X(pause) ws (14)
N(play) w; (14)
z (recording) wa (15, 16)
.m(rewind) qa (14)
ZPUSH OPEN/CLOSE qf (14)
x(stop) ql (14, 15)

5
HCD-EP404
ALPHABETICAL ORDER
A – M
CD wf (8, 9, 15)
CLOCK/TIMER +/– w; (16, 18)
CLOCK/TIMER ON/OFF 2
(16, 18)
CLOCK/TIMER SET 3(7, 16,
18)
DISPLAY qa (12, 19)
ENTER qf (7, 9, 10, 11, 13, 18)
MEGA BASS qd (17)
MUSIC MENU +/– qh (17)
MUTING qg (17)
P – Z
PLAY MODE 7(8, 9, 13, 14, 15)
PRESET +/– 9(11, 13)
REPEAT 8(8)
SLEEP 1(17)
TAPE wd (14)
TUNER/BAND 5(10, 11, 12,
15)
TUNER MEMORY qj (10, 11)
TUNING + q; (10, 11, 12, 13)
TUNING – qk (10, 11, 12, 13)
VOL (volume) +/– qs
Remote control
BUTTON DESCRIPTIONS
m(rewind) M(fast forward)
ql (8, 14)
.(go back) >(go forward)
w; (7, 8, 14, 15)
X(pause) ws (8, 14)
N(play) wa (8, 9, 14, 15, 16)
`/1(power) 4(7, 16, 18)
x(stop) 6(8, 9, 14, 15)
Setting the clock
1Turn on the system.
2Press CLOCK/TIMER SET on the
remote.
3Press .or >on the remote
repeatedly to set the hour.
4Press ENTER.
5Press .or >on the remote
repeatedly to set the minute.
6Press ENTER.
The clock starts working.
To adjust the clock
1Press CLOCK/TIMER SET on the remote.
2Press .or >on the remote to select
“SET CLK”, then press ENTER.
3Do the same procedures as step 3 to 6 above.
Note
The clock settings are canceled when you disconnect
the power cord or if a power failure occurs.

6
HCD-EP404
SECTION 3
DISASSEMBLY
•The equipment can be removed using the following procedure.
3-1. Front Panel Section
Note : Follow the disassembly procedure in the numerical order given.
3-6. CD CABINET SECTION
(Page 9)
3-5. DISPLAY BOARD,
HEADPHONE BOARD
(Page 8)
3-1. FRONT PANEL SECTION
(Page 6)
3-3. TAPE MECHANISM DECK
(CFL4318)
(Page 7)
3-7. CD MECHANISM DECK
(CS-21SC-1280)
(Page 9)
3-8. CASSETE LID
(Page 10)
3-2. MAIN BOARD
(Page 7)
3-4. POWER BOARD,
POWER TRANSFORMER
(Page 8)
SET
qa connector
(CN201)
6 two screws
(+K3
× 5)
3 two screws
(+BTP2.6
× 10)
1 screw
(+BVTP3
× 10)
4 two screws
(+BVTP3
× 10)
5 two screws
(+K3
× 5)
7 two screws
(+K3
× 5)
qs connector
(CN402)
q; connector
(SW600)
qd front panel section
9
2 antenna cover cabine
t
8 claw
Ver 1.1 2002.07

7
HCD-EP404
3-2. MAIN Board
3-3. Tape Mechanism Deck (CFL4318)
6 connector
(CN703)
7 connector
(CN702)
5 connector
(CN402)
4 connector
(CN701)
3 connector
(CN601)
2 connector
(CN705)
1 connector
(CN704)
q; MAIN board
9 claw
8 screw
(+BTP2.6
× 8)
2 two screws
(+BVTP3
× 10)
1 two screws
(+BVTP3
× 10
)
3 tape mechanism deck (CFL4318)
Ver 1.1 2002.07

8
HCD-EP404
3-4. POWER Board, PowerTransformer
3-5. DISPLAY Board, HEADPHONE Board
8 screw
(+BTP2.6
× 8)
3 screw
(+BVTP3
× 10)
1 screw
(+BVTP3
× 10)
4 four screws
(+BVTP3
× 12)
5 power transformer
q; POWER board
9 power pwb mounting bkt
2 ac cord holder
6 Remove four solderings.
7 Remove four solderings.
rear cabinet assy
7 screw
(+PTPWH2.6 × 10)
qa HEADPHONE board
9 Remove the soldering.
q; earth wire
8 reteiner board
6 DISPLAY board
5 main pwb mounting bk
t
4 seven screws
(+BTP2.6 × 10)
1 vol. rotaly knob
2 washer
3 nut

9
HCD-EP404
3-6. CD Cabinet Section
3-7. CD Mechanism Deck (CS-21SC-1280)
1 two screws
(+BTP2.6 × 8
)
2 CD cabinet section
1 two screws
(BVTP3 × 8)
4 CD cover housing
qa vibration proof rubber
(pink)
qs vibration proof rubber
(pink)
6 four fiber washers
5 four pulley screws
q; vibration proof rubber
(orange)
qd vibration proof rubber
(orange)
qf CD mechanism deck (CS-21SC-1280)
7
3
8 two spring clamps
9 two spring clamps
2 Remove the connector.

10
HCD-EP404
3-8. Cassette Lid
3 cla
w
3 claw
2
5 cassette lid
4
1 Push
open/close switch

11
HCD-EP404
SECTION 4
MECHANICAL ADJUSTMENTS SECTION 5 ELECTRICAL ADJUSTMENTS
PRECAUTION
1. Clean the following parts with a denatured-alcohol-moistened
swab : record/playback head pinch roller
erase head rubber belts
capstan idlers
2. Demagnetize the record/playback head with a head
demagnetizer.
3. Do not use a magnetized screwdriver for the adjustments.
4. After the adjustments, apply suitable locking compound to the
parts adjusted.
5. The adjustments should be performed with the rated power
supply voltage unless otherwise noted.
Torque Measurement
TapeTension Measurement
Mode Torque Meter Meter Reading
FWD CQ-403A more than 100 g
(more than 3.53 oz)
PRECAUTION
1. Setting
MEGA BASS switch : OFF
TAPE DECK SECTION 0 dB=0.775 V
Test tape
Mode Torque Meter Meter Reading
2.95 – 6.86 mN•m
FWD CQ-102C (30 – 70 g•cm)
(0.42 – 0.97 oz•inch)
0.15 – 5.39 mN•m
FWD CQ-102C (1.5 – 5.5 g•cm)
Back Tension (0.021 – 0.076 oz•inch)
more than 5.89 mN•m
FF CQ-201B (more than 60 g•cm)
(more than 0.83 oz•inch)
more than 5.89 mN•m
REW CQ-201B (more than 60 g•cm)
(more than 0.83 oz•inch)
Type Signal Used for
P-4-A100 10 kHz, –10 dB Head Azimuth Adjustment
WS-48B 3 kHz, 0 dB Tape Speed Adjustment
Record/Playback Head Azimuth Adjustment
Procedure:
1. Mode: Playback
level meter
test tape
P-4-A100
(10 kHz, –10 dB)
set
HEADPHONE board
PHONES jack (JK501
)
32 Ω
+
–
2. Turn the adjustment screw and check output peaks. If the peaks
do not match for L-CH and R-CH, turn the adjustment screw
so that outputs match within 1dB of peak.
3. Mode: Playback
4. After the adjustments, apply suitable locking compound to the
parts adjusted.
Screw
position
L-CH
peak
within
1dB
Output
level
L-CH
peak R-CH
peak
within
1dB
Screw
position
R-CH
peak
test tape
P-4-A100
(10 kHz, –10 dB)
L-CH
R-CH HEADPHONE board
PHONES jack (JK501)
oscilloscope
VH
++
––
screen pattern
in phase good wrong
45 °
90 °
135 ° 180 °
32 Ω
32 Ω
set

12
HCD-EP404
Tape Speed Adjustment
Setting:
Function: TAPE
Procedure:
1. Playback WS-48B (tape center).
2. Adjsut the volume in CAPSTAN/REEL motor so that the
frequency counter reading becomes 3,000 Hz.
Specified Value: 2,910 to 3,090 Hz
3. Confirm that the frequency at the beginning and that at the end
of tape winding are between 2,955 to 3,045 Hz.
Adjustment Location:
frequency counte
r
test tape
WS-48B
(3 kHz, 0 dB)
set
HEADPHONE board
PHONES jack (JK501)
–
+
32
Ω
CAPSTAN/REE
L
motor
Tape Speed
Adjustment
Adjustment Location: Record/Playback Head.
Note: Refer to “3-8.Cassette Lid” (see page 10)
adjustment screw

13
HCD-EP404
TUNER SECTION 0 dB=1 µV
[AM]
Setting:
Function : TUNER
Band switch : AM
[FM]
Setting:
Function : TUNER
Band switch : FM
•Repeattheproceduresineach adjustment severaltimes,and the frequency
coverage and tracking adjustments should be finally done by the trimmer
capacitors.
AM RF signal
generator
30% amplitude
modulation by
400 Hz signal
Output level: as low as possible
Put the lead-wire
antenna close to
the set.
+
–
level meter
set
32 Ω
HEADPHONE board
PHONES jack (JK501
)
FM RF signal
generator
22.5 kHz frequency
deviation by 400 Hz
signal
Output level: as low as possible
+
–
level meter
set
32 Ω
0.01 µ F
MAIN board
FM ANT
HEADPHONE board
PHONES jack (JK501
)
digital voltmeter
100 k Ω
MAIN board
TP (FM VT)
TP (AM VT)
AM FREQUENCY COVERAGE ADJUSTMENT
Adjustment Part Frequency Display Reading on Digital Voltmeter
Confirmation 531 kHz 1.5 ±0.2 V
T101 1,602 kHz 7.3 ±0.3 V
AM TRACKING ADJUSTMENT
Adjust for a maximum reading on level meter
L110 603 kHz
TC102 1,404 kHz
FM FREQUENCY COVERAGE ADJUSTMENT
Adjustment Part Frequency Display Reading on Digital Voltmeter
L103 87.5 MHz 2.1 ±0.2 V
Confirmation 108 MHz 7.0 ±0.4 V
FMTRACKING ADJUSTMENT
Adjust for a maximum reading on level meter
L102 89.9 MHz
TC101 105.9 MHz
Adjustment Location: MAIN board (See page 14)

14
HCD-EP404
Adjustment Location and Connecting Points
– MAIN BOARD (Component Side) –
L104
}
AM Tracking
TC102 Adjustment
TC102
}
FM Tracking
L102 Adjustment
L103 FM Frequency
Coverage Adjustment
T101 AM Frequency
Coverage Adjustment
IC101
– MAIN BOARD (Conductor Side) –
TP(AM VT)
TP
(FM VT)

1515
HCD-EP404
Note on Schematic Diagram:
• All capacitors are in µF unless otherwise noted. p: pF.
50 WV or less are not indicated except for electrolytics
and tantalums.
•All resistors are in Ωand 1/4W or less unless otherwise
specified.
•2: nonflammable resistor.
•C: panel designation.
Note on PrintedWiring Board:
•W: indicates side identified with part number.
•: Pattern from the side which enables seeing.
(The other layers' patterns are not indicated.)
•Indication of transistor
•A: B+ Line.
•H: adjustment for repair.
•Voltagesaretakenwith aVOM(Inputimpedance 10 MΩ).
Voltage variations may be noted due to normal produc-
tion tolerances.
•Waveforms are taken with a oscilloscope.
Voltage variations may be noted due to normal produc-
tion tolerances.
no mark : FM
<>:CD (STOP)
•Circled numbers refer to waveforms.
•Signal path.
F: FM
f: AM
E: PB (TAPE)
a: REC (TAPE)
J: CD PLAY
•WAVEFORMS
– MAIN Board – – CASSETTE Board – – DISPLAY Board –
1 IC102 ws (XOUT)
3.4 Vp-p
139 ns
1 V/DIV, 40 ns/DIV
2 Q715 (Collector)
(RECORD (1SS) mode)
2 V/DIV, 4 µ s/DIV
3 IC601 i; (X2)
1 V/DIV, 100 ns/DIV
8.6 Vp-p
12.7
µ s5.1 Vp-p
238 ns
B
These are omitted.
CE
SECTION 6
DIAGRAMS
6-1. Circuit Boards Location
Note: The components identified by mark 0or dotted line
with mark 0are critical for safety.
Replace only with part number specified.
MAIN board
LED board
HEADPHONE board
DISPLAY board
POWER boar
d

1616
HCD-EP404
6-2. Block Diagrams
TUNER/TAPE DECK Section
: FM
: AM
• Signal Path
• R-CH is omitted due to same as L-CH.
: PB(TAPE)
: REC(TAPE)
9
13
12
11
1
3
105
15
7
7
16
18
19
20
15
8
11 12
6
4
5
3
122
Q103
FM OSC
BUFFER
Q102
BAND
SWITCH
Q101
AMP
BPF
AMRF_IN
AM_OSC
24 FMRF_IN
22 FM_RF
FM_OSC
20
FM_IF
AM
OSC_OUT
FM
ANT
L104
AM ANT
D105 T101
AM OSC
L102
FM RF
D103
D104 L103
FM OSC
F102
10.7MHz
T102
X101
10.7MHz
PD
AIN
AOUT
FMIN
AMIN
BO1
IO1
IFIN
DO
DI
CL
CE
IC102
FM/AM PLL
X102
7.2MHz
XIN XOUT
AM_MIX
FM_MIX
FM_DET
AGC
AM/FM
IF_OUT
AM_IF
16
17
L_OUT
R_OUT
IC101
AM/FM IF AMP,
MIX, MPX, DET, OSC
72 20 76 6
DATAIN DA-IN
PLL-CE
STATION
STEREO
PLLENA
STATION
STEREO
DA-IN
STEREO
DI
PLL-CE
CL
STATION
A
AMP
SECTION
AMP
SECTION
B
AMP
SECTION
C
AMP
SECTION
D
PANEL
SECTION
E
IC301 (1/3)
SYSTEM CONTROLLER
R-CH
TUNER
L-CH
TC102
TC101
FM FREQUENCY
COVERAGE
AM FREQUENCY
COVERAGE
AM TRACKING
FM TRACKING
F103
450kHz
MOTOR-ON
IC701
REC/PB SWITCH
IC702
ALC,
REC/PB AMP
R-CH
Q718
R-CH
L-CH
(RECORD/PLAYBACK)
R-CH R-CH
95
REC-EN
16
6
7
3
4
4
8
7 9
(PROTECT (FWD) DETECT)
(HALF SWITCH)
Q705
REC/PB
SWITCH
Q701
REC/PB
SWITCH
Q703
AMP GAIN
CONTROL
Q719
ALC
CONTROL
ALC
BIAS
TRAP Q720,721
CAPSTAN/REEL
MOTOR DRIVE
SENSORA
90
BLINK
70
AMS
68
24/12
66
T701
BIAS OSC
9V
Q716,717
REC BIAS
SWITCH
M
(CAPSTAN/REEL)
SOL
93
Q722,723
TRIGGER
PLUNGER DRIVE
(TRIGGER PLUNGER)
R-CH
R-CH R-CH
R-CH
R-CH
R-CH
(MODE SWITCH)
D305 D308
D703
D701 D702
TL-CH
TR-CH
RL-CH
RR-CH
(ERASE)
SWITCHING
R-CH
ISS SWITCHING
Q724
TAPE PLAY DETECT
SENSOR
Q711
REC AMP
Q713
PB AMP
Q707
MUTING
Q715
BIAS OSC
ALC
IN
OUT
ALC
CNTRL
IN
NF
2
DI
CL
STA_B+
2SS
1SS
SW601
BEAT CUT

1717
HCD-EP404
AMP Section
• Signal Path
• R-ch is omitted due to same as L-ch.
: FM
: CD
: PB(TAPE)
: REC(TAPE)
IC401
FUNCTION SELECT SWITCH,
ELECTRONIC VOLUME
Q403,404
MUTING
Q401
MEGA BASS
R-CH
R-CH
R-CH
LTCOM
LTOUT
LVRIN
LVROUT
L3
CD L-IN
CD L-IN
CD R-IN
CD-DA
CD-CLK
CDRS
TUNER
L-CH
TL-CH
TR-CH
R-CH
R-CH
R-CH
L4
L2
DI CE
2117
INPINENA
MUTE
1
10
9
11
15 16
22
5 7
10
3
4
L1 12
73
DATAOUT
15
CDRESET
88
CDCLK
14
CDDATA
D402
D403
D401
+
+
–
+
–
SPEAKER
IMPEDANCE
USE 8Ω
L
R
PHONES
JK501
IC301 (2/3)
SYSTEM CONTROLLER
CL
14
74
CLK
19
SOUNDENA
CD BLOCK
DI
CL
IC601
POWER AMP
IC302
EEPROM
X2
X1
X301
4.194304MHz
79 80
EEPROMDATA
75
CD DOOR SW
91
SDA
5
SCL EEPROMCLK
77
6
ZPUSH
OPEN/CLOSE
A
D
TUNER
SECTION
TAPE
SECTION
CTAPE
SECTION
BTUNER
SECTION
RR-CH
RL-CH
R-CH
STK601

1818
HCD-EP404
DISPLAY/POWER Section
X302
REMOTE CONTROL
RECEIVER
IC603
+12V
REGULATOR
IC602
+9V
REGULATOR
IC304
RESET SIGNAL
GENERATOR
IC301 (3/3)
SYSTEM CONTROLLER,
LIQUID CRYSTAL DISPLAY DRIVER
Q205, 206
POWER ON/OFF
RELAY DRIVE
T201
POWER
TRANSFORMER
(MAIN)
AC IN
T202
POWER
TRANSFORMER
(SUB)
RE201
B+ AMP
POWER AMP (IC601)
D601
D107
CD-EN
D604
RESET 84
POWERFAIL 86
92
TU-EN 94
3 1
3 1
D901 – 903
(LCD BACK LIGHT)
851 REMOTEIN
ROTARY
ENCODER
ENCODERA
97
ENCODERB
98
LCD34
62
LCD35
63
LCD36
64
LCD33
61
LCD32
60
100, 1 – 4
COM0 – COM3 KEY1 – KEY5
23 – 26
LCD04 – LCD31
32 – 59
SW301 – 317
X303
VOLUME
LIQUID CRYSTAL
DISPLAY
D205 - 208
RECT
D215 - 218
RECT
D212, 213
RECT
D201 - 204
RECT
Q604
+9V
REGULATOR
Q603
+5V
REGULATOR
Z202
+6.2V
REGULATOR
Z201
+6.8V
REGULATOR
CD9V
9V
TAPE DECK SECTION
M12V
CAPSTAN/REEL MOTOR B+
SYSTEM CONTROLLER (IC301) VDD,
EEPROM (IC302)
SYSTEM CONTROLLER (IC301) AVREF
Q605,606
REGULATOR
CONTROL SWITCH
FM/AM PLL (IC102)
3
1
RDSDATA 7
POWER 22
Q306
RESET
SWITCH
D303 D302
SWITCHING
Q301
SWITCHING
Q104
B+ SWITCH
REC-LED
18
Q305
LED
DRIVE
D313
TIME
13
Q304
LED
DRIVE
D312
z
TIMER
D603
D309
D310
D602
STA_B+
TAPE
SECTION
E

1919
HCD-EP404
6-3. PrintedWiring Board MAIN Section • See page 15 for Circuit Boards Location.
IC602IC603
IC601
IC401
IC101
IC102
IC702
IC701
K
K
K
K
K
K
K
K
K
K
K
A
A
A
A
A
A
A
K
K
A
A
A
A
A
A
E
E
EE
K
K
K
K
K
A
A
A
A
K
A
KA
E
E
E
EE
E
E
E
E
E
A
E
E
E
E
E
E
E
E
E
E
E
E
E
E
E
E
E
E
E
E
MAIN BOARD
HEADPHONE
BOARD
R706
R722
POW
-FA
PHOTO
MODE
PHONES
SPEAKER
(IMPEDANCE USE 8 )
L
R
TO
POWER
BOARD
CN505
(Page 25)
A
TO
DISPLAY
BOARD
(Page 23)
B
TO
DISPLAY
BOARD
(Page 23)
C
FM
ANT
FM
LEAD ANTENNA
(MODE)
(HALF)
(PROTECT(FWD))
(CAPSTAN/REEL)
(TRIGGER PLUNGER)
TAPE PLAY
DETECT SENSOR
M
CD
BLOCK
SUPPLIED AS THE
ASSEMBLED BLOCK
TO
DISPLAY
BOARD
(Page 23)
D
TO
DISPLAY
BOARD
(Page 23)
E
(R-CH)
(ERASE)
(L-CH)
(RECORD/PLAYBACK HEAD)
(ERASE HEAD)
L104
AM FERRITE-ROD
ANTENNA
13
BEAT CUT
1SS
2SS
1SS
2SS
TP
(AM VT)
TP
(FM VT)
12
A
B
C
D
E
F
345678 9
Ref. No. Location
D101 B-4
D102 B-4
D103 B-4
D104 B-4
D105 B-4
D107 C-7
D401 D-4
D402 D-4
D403 D-4
D404 E-6
D405 D-7
D601 E-6
D604 F-5
D701 B-8
D702 B-8
D703 C-8
D704 B-8
D706 F-7
IC101 C-5
IC102 C-6
IC401 D-5
IC601 E-4
IC602 F-5
IC603 F-5
IC701 A-7
IC702 B-7
Q101 C-5
Q102 C-4
Q103 C-4
Q104 B-6
Q401 D-4
Q402 D-4
Q403 E-5
Q404 E-5
Q603 E-5
Q604 F-6
Q605 E-6
Q606 E-6
Q701 B-7
Q702 B-8
Q703 B-7
Q704 B-8
Q705 B-7
Q706 B-8
Q707 C-7
Q708 C-8
Q711 D-7
Q712 C-8
Q713 C-7
Q714 C-7
Q715 B-8
Q716 B-8
Q717 B-8
Q718 C-8
Q719 C-7
Q720 F-8
Q721 E-7
Q722 F-7
Q723 F-7
Q724 A-8
ZD601 F-6
ZD602 E-5
• Semiconductor
Location

2020
HCD-EP404
6-4. Schematic Diagram MAIN Section (1/3) • See page 15 for Waveforms. • See page 27,28 for IC Block Diagrams.
2.4
<0.9>
1.3 1.3
3.6 3.6 3.6 3.6 3.6 3.6 3.6 3.6 3.3
0 0
3.6 3.6 3.6 3.6 3.6 3.6 3.6 3.6 3.3
0 0
3.3 3.6
0 <0.1>
0
1.8 <0.1>
3.7 <0.1>
0.9 <0.4> 0.9 <0.4>
2.1 <9>
1.8 <0>
5 <6>
5
<5.6>
0 <0.4>
2.6 <3.3>
5 <5.7>
1.3
4.8 <5.7>
1.3
5 <5.7> 5 <5.8>
1.1 <0.8>
1.3
1.3
1.2
3.3 7.2 4.8
0
0
4.2 <0>
4.3
<3.4>
4.2
<5.2>
0
<0.6>
4.2
<0>
5
<0.1> 2.7
5.4
2
0.1
<0.6>
1
<0>
5 <5.8>
0
<0.2>
0 <4.8>
5.4 4.8
0
0
1.9 <0>
1
8.5
3.8
<0>
4.4
<0.4>
0
0.6
0.6
2.4
0
0
2.4
0
0.022
4.7k
3.3k
0.022
AM FERRITE-ROD
ANTENNA
L104, TC102
AM TRACKING
FM
LEAD ANTENNA
FM
ANT
BPF
1SS133T
1SS133T
0.001
0.1 0.1
0.1 0.1 0.1
0.1
0.1
0.047
3.9k
1SS133T
0.0056
0.022
0.0047 0.033
8.2k
6.8k
6.8k
2.2k 2.2k 0.22
0.22
10k 10k
2SC945
2SC945
0.0047
0.022
8.2k
3.9K
0.047
0.0056
0.1 0.1
0.1
0.1
0.001
0.001
0.001
0.001
0.01 0.01
0.0015 0.0015
0.022
2SC945 0.01
2SC1923
2SC945
0.047
100p
0.001 0.001
0.01
0.1
0.1
2SC3623
1SS133T
8.2k
8.2k
330
DTC343TS DTC343TS
0.1 0.047
MAIN BOARD (1/3)
TP
(AM VT)
TP
(FM VT)
CD
BLOCK
SUPPLIED AS
THE ASSEMBLED BLOCK
Q403,404
MUTING
BAND
SWITCH
TO
DISPLAY
BOARD
B
(Page 24)
TO
DISPLAY
BOARD
E
(Page 24)
MAIN
BOARD(2/3) (3/3)
4
IC102
FM/AM PLL
B+ SWITCH
FM OSC
BUFFER
AMP
IC101
IC B/D
AM/FM IF AMP
MIX,MPX,DET,OSC
MEGA
BASS
MEGA
BASS
IC401
FUNCTION SELECT SWITCH,
ELECTRONIC VOLUME
L103
FM FREQUENCY
COVERAGE
T101
AM FREQUENCY
COVERAGE
L102, TC101
FM TRACKING
IC B/D
IC B/D
MAIN
BOARD (2/3)
5
MAIN
BOARD(3/3)
7
MAIN
BOARD
(2/3)
MAIN
BOARD
(2/3)
2
1
12
A
B
C
D
E
F
G
H
I
345678910111213