Kenwood GC-401-EF-2 Service manual

CD CASSETTE RECEIVER

GX-401EF2

SERVICE MANUAL

SUBAR U GENUINE

DISP

SCAN

MUTE

TUNE/ TRACK

Knob (SEEK) (K23-1065-04)

Front glass (B10-4256-03)

LOCAL

LOUD

BNR2REP3RDM4PROG

Knob (CS EJ) (K24-3876-04)

Cassette lid (A53-1703-03)

Knob (1,3,5) (K25-1462-03)

DOLBY B NR

Knob (2,4,6) (K25-1463-03)

Blind plate (F19-1357-04)

NEWS T/B

Knob (NEWS) (K24-3877-04)

Knob (T/B) (K24-3878-04)

COMPACT

DIGITAL AUDIO

REG

TONE/ BAL

Knob (VOL) (K23-1066-04)

Panel assy (A64-2724-02)

VOL ADJ

T.I

BAND

TAPE

PUSH

POWER

VOLUME

BRIGHT

Cord with plug (E30-6075-05)

Holder (J19-5161-05) x 2

GX -401EF2

BLOCK DIAGRAM

ANT.

IC13

CD MECHA

(X25)

B/2

CASSETTE MECHA

A11

TUNER PACK

RDS

IC21

SW-AMP

IC1

EQ, DOLBY

IC2

MOTOR DRIVER

IC22

(X25) A/2

ED1

CD-CH

MPX E-VOL

IC1

VFD

IC31,32

FIX-EQ

IC84

MEMORY

IC81

SYSTEM u-COM

PANEL u-COM

KEY MATRIX

MUTE

IC41

POWER AMP

LAMP

IC82

RESET

Q101

FM+B SW

Q103

AM+B SW

Q94

P-ANT

Q709

BU-DET

Q904

ACC-DET

Q706

BU5V AVR

Q708

PON5V SW

Q704

A8V AVR

Q701

CD7V AVR

Q710

C5V AVR

Q605,606

LAMP AVR

A61

DC/DC

(X14)

SP-OUT

P-ANT

ACC TEL-MUTE

SMALL

L12

DME

CD-MECHA

CME

CASSETTEMECHA

CD-CH

A11ANT

TUNER

CD : 1200mV

TAPE : 540mV

CD-CH : 1200mV

IC21

SWAMP

FM : 220mV

AM : 150mV

IC22

0dB

CD TAPE CH FM AM

MPX,LOUD, E-VOL, BASS,TRE, FAD,BAL

: +7dB : +15dB : +7dB : +15dB : +14dB

Level difference of each source

1kHz 30% mod.

1kHz 40kHz dev.

IC31,32

FIX EQ

-11dB

-19dB

1kHz 0dB 1kHz 0dB 1kHz 0dB 0dB

TAPE

-9.7dB

-5.7dB

IC41

POWER AMP

+34dB

-14dB

0dB

FRONT SP

REAR SP

GX-401EF2

COMPONENTS DESCRIPTION

● Synthesizer Unit (X14-6212-71)

Ref.No Application / Function Operation / Condition

IC1 Dolby B / Tape EQ amplifier Playback EQ / Dolby B / between music detection

IC2 Motor driver For cassette mechanism IC12 Ope-amplifier RDS noise amplifier IC13 RDS decoder RDS decode IC21 Switch / Ope-amplifier CD/TAPE switch IC22 Electronic volume BASS/TRE/MPX/EV

IC31,32 Ope-amplifier FIX-EQ

IC41 Power amplifier 4 channel/35W power amplifier IC71 AVR control AUDIO+8V power supply IC72 Ope-amplifier 1/2VCC output IC81 System computer System control IC82 Reset IC Reset detection IC84 EEP-ROM Memory backup

Q1 Cassette mechanism main motor power switch Cassette mechanism main motor Q2 Cassette mechanism main motor power switch Pch-SW Q3 Gain switching when tape selected music Pch-SW, ON when playback a tape

Q94 P-ANT circuit control switch P-ANT circuit control Q101 FM power switch FM 8V Q102 FM power switch Pch-SW Q103 AM power switch AM 8V Q104 AM power switch Pch-SW Q107 IF mode switch by force Output “Lo” when WIDE Q108 Noise amplifier Noise detection ouput buffer

Q109,110 Noise amplifier Noise detection time constant switching

Q201 Switch for source Output “Lo” when TAPE Q202 MUTE switch CD mute Q203 MUTE switch ICll3 hard mute Q204 MUTE switch CD mute (Rch) Q205 MUTE switch CD mute (Lch) Q601 AVR switch for DC/DC Pch-SW Q603 AVR for DC/DC 13V AVR Q604 AVR control for DC/DC 13V AVR

Q605,606 AVR for lamp 9V AVR

Q607 AVR switch for lamp Nch-SW Q608 AVR control for lamp 9V AVR Q609 SMALL detection Output “Lo” when SMALL ON Q701 AVR for CD mechanism 7V AVR Q702 AVR control for CD mechanism 7V AVR Q703 AVR switch for CD mechanism 7V AVR Q704 AVR 8V AVR Q705 AVR switch 8V AVR

GX -401EF2

COMPONENTS DESCRIPTION

Ref.No Application / Function Operation / Condition

Q706 AVR for microcomputer 5.6V AVR Q707 AVR control for microcomputer 5.6V AVR Q708 Switch for P-ON 5V Switch for P-ON 5V Q709 BU detection Output “Lo” when BU ON Q710 Cassette mechanism sub-motor driver power switch Sub-motor driver VREF Q801 MUTE switch ICll3 and POWER IC hard mute Q802 DSI control Output “Hi” when DSI light on

Q803 AVR control switch ON when P-ON 5V ON Q804,805 MUTE switch ICll3 and POWER IC hard mute Q901,902 P-ANTcircuit protection Antena short circuit protection

Q903 P-ANT circuit control switch P-ANT circuit control

Q904 ACC detection Output “Lo” when ACC ON

● Switch Unit (X25-9382-70)

Ref.No Application / Function Operation / Condition

IC1 Display control microcomputer VFD control / Key matrix Q1 5V control Nch-SW Q2 VFD power switch Pch-SW Q3 5V control VFD protection switch

MICROCOMPUTER’S TERMINAL DESCRIPTION

● System Microprocessor : UPD784216AGF-529-3BA (X14 : IC81)

Pin Pin name I/O Description / Processing Operation

1 AM+B O AM power output. “H” : AM 2 FM+B O FM power output. “H” : FM 3 P_MUTE O P-AMP IC mute. “L” : Mute on 4 P_STBY O P-AMP IC power control. “H” : ACC on, “L” : ACC off 5 CD_LOE/LIM_SW I CD DOWN LIMIT switch. “H” : Chucking 6 CD_MOTOR O CD motor driver control. “H” : Loading/Eject mode, “L” : Other mode 7 CD_LO/EJ I/O CD loading/eject motor control switch. “Hi-Z” : Normal (“L” : MOTOR), “H” : Eject, “L” : Loading 8 CD_MSTOP O CD mechanism standby control. “H” : CD mechanism on, “L” : CD mechanism off

9 VDD 10 CD_MRST O CD mechanism reset control. “L” : Reset 11 CD_MUTE_L I MUTE request from CD mechanism. “L” : Mute on request 12 BEEP O BEEP output. 13 NC O Not used (N.C.) 14 CD_I2CDATA I/O CD mechanism data input/output. 15 CD_I2CCLK I/O CD mechanism clock input/output. 16 NC O Not used.

GX-401EF2

MICROCOMPUTER’S TERMINAL DESCRIPTION

Pin Pin name I/O Description / Processing Operation

17 CD_MUTE_R I MUTE request from CD mechanism. “L” : Mute on request 18 NC O Not used (N.C.) 19 NC O Not used (N.C.) 20 REF_CONT O Voltage control of Avref. “H” : Active 21 CH_REQH O Communication reqest to CH. 22 TEST I 23 TYPE1 I Tuner 1 setting. Set up terminal for frontend test mode 24 TYPE2 I Tuner 2 setting. Set up terminal for frontend test mode 25 CD_LOS_SW I CD loading detection switch. “L” : Disc, “H” : No disc, “L”→“H” : Loading start 26 CD_12EJE_SW I 12cm disc detection switch. “L” : 12cm disc detected, “H” : Fixed by 8cm disc detected 27 MUTE O Audio mute. “L” : Mute on 28 P_ON O Peripheral power control. “L” : ACC on/PWR on, “H” : PWR off/ACC off 29 CH_CON O CH control output. “H” : CH on” 30 CH_RST O CH reset. “H” : CH reset 31 CH_MUTE I MUTE request from CH. “H” : Mmute request 32 ANT_CONT O Power antenna control. “H” : PWR on 33 DC/DC O 34 NC O Not used (N.C.) 35 NC O Not used (N.C.) 36 M_MOTOR O CD mechanism main-motor control. “H” : Motor on 37 VDD - Power supply. 38 X2 - Main clock (12MHz). 39 X1 I Main clock (12MHz). 40 VSS - GND. 41 XT2 - Sub clock (32.768kHz). 42 XT1 I Sub clock (32.768kHz). 43 RESET I “H” input after initialise. “L” : Reset (less than 3V) 44 BU_DET I BU detection. “L” : Normal, “H” : Power down 45 NC O Not used (N.C.) 46 ACC_DET I ACC detection. “L” : ACC on, “H” : ACC off 47 ILLM_OUT O Lamp control. “H” : Lamp on 48 CH_REQC I Changer comm unication request input. 49 SC_REQ I Panel communication request input. 50 R_CLK I RDS clock. 51 AVDD - Analog power for A/D. 52 AVREF0 - Reference voltage input for A/D. 53 SMALL I SMALL detection. “L” : SMALL on 54 PHONE I TEL detection. ≤1V : TEL mute 55 R_REEL I Cassette mechanism reel pulse input. Reverse rotation photo input 56 F_REEL I Cassette mechanism reel pulse input. Forward rotation photo input 57 NC I Not used (N.C.) 58 NOISE I Noise level. 59 SMETER I S-METER level.

VFD display power control. “H” : Power on. Panel µcom VFD-ON terminal confirm “H” after that set “H”.

GX -401EF2

MICROCOMPUTER’S TERMINAL DESCRIPTION

Pin Pin name I/O Description / Processing Operation

60 MODE3 I Cassette mechanism positioning mode pluse input. FF/REW/FWD/REV detection 61 AVSS - GND for A/D. 62 SC_CON O Panel microcomputer operation control output. 63 SC_BUSY I Panel BUSY input. 64 AVREF1 - D/A reference voltage input. 65 CH_DATAC I Data input from changer. 66 CH_DATAH O Data output to changer. 67 CH_CLK I/O Clock output to changer. 68 SC_DATA I Data input from Panel microcomputer. 69 MC_DATA O Data output to Panel microcomputer. 70 MC_CLK O Clock output to Panel microcomputer. 71 MC_REQ O Communication request output to Panel microcomputer. 72 NC O Not used (N.C.) 73 PLL_CE O PLL IC chip enable control. 74 PLL_DATA O Data output to PLL IC. 75 PLL_CLK O Clock output to PLL IC.

76 DSI O

77 NC O Not used (N.C.) 78 SUB_P O Cassette mechanism sub-motor control. 79 SUB_M O Cassette mechanism sub-motor control. 80 NC O Not used. 81 R_DATA I RDS DATA. 82 QUAL I RDS quality (Receiving mode). 83 MTL_OUT O Cassette mechanism output invert data, when metal detection. “H” : Metal, “L”: Normal 84 MUSIC I Cassette mechanism between-music detection. “H” : Between-music, “L” : Music 85 MSGV O When Cassette mechanism select music, gain switching. “H” : Normal, “L” : FF/REW/DPSS 86 F/R O Cassette mechanism F/R switching. “L” : FWD/Initial mode, “H” : REV 87 METAL I Cassette mechanism metal detection. “H” : Normal, “L” : Metal 88 DOLBY O Cassette mechanism Dolby switching. “H” : On, “L” : Off/Initial mode 89 EQ_MUTE O Cassette mechanism EQ mute. “L” : Play, “H” : FF/REW/DPSS 90 MODE2 I Cassette mechanism positioning mode pulse input. FF/REW/FWD/REV detection 91 MODE1 I Cassette mechanism positioning mode pulse input. FF/REW/FWD/REV detection

92 AFC O

93 IF_MODE I K2I IF detection. “H” : WIDE, “L” : NARROW 94 WIDE O K2I enforced WIDE. 95 NARROW I/O K2I enforced NARROW. 96 FM_SD I FM SD input. “H” : Station detected, “L” : Station not detected 97 SDA_IC2 I/O Electronic volume data input/output. 98 SCK_IC2 O Electronic volume clock output. 99 A_SEL O AUDIO selection. CD/TAPE switching. “L” : CD, “H” : TAPE

100 VSS - Connected to GND.

Security LED control. “L” : Indicator light on, ACC off : 100ms light on (cycle is 2s), ALL off : Light off, During operation : Light on

AFC REQUEST output. Noise detection output time constant switching (FM), “L” : FM and AM seek, “H” : Normal receiving

GX-401EF2

MICROCOMPUTER’S TERMINAL DESCRIPTION

● Panel Microprocessor : UPD780021AGC-106-8BS (X25 : IC1)

Pin Pin Name I/O Description / Processing Operation

1~4 KS0~KS3 O Key scan signal output 0~3

5 VFD_BLK O VFD dr iv er blank output

6~8 NC O Not used (OPEN)

9 VSS GND

10 VDD Positive pow er supply

11~14 NC O Not used (OPEN)

15 VFD_LAT O VFD SIO latch 16 VFD_DATA O VFD driver data output 17 VFD_CLK O VFD driver clock output 18 MC_DATA I System computer communication data input 19 SC_DATA O System computer communication data output 20 MC_CLK I System computer communication clock input 21 SC_BUSY O System computer panel BUSY output

22,23 NC O Not used (OPEN)

24 AVDD Positive power supply 25 AVSS GND 26 ENC_UP I Encoder input (UP) 27 ENC_DOWN I Encoder input (DOWN)

28~33 NC I Not used

34 AVREF I GND 35 AVDD Not used 36 RESET I Reset input “L” : Reset 37 XT2 Not used 38 XT1 I Not used (GND) 39 IC/VPP Not used 40 X2 Main clock (8.38MHz) 41 X1 I Main clock (8.38MHz) 42 VSS1 GND 43 SC_CON I System computer communication and panel operation control input 44 MC_REQ I System computer communication and receive request input

45,46 KR1,KR0 I Key return signal input 1,0

47 SC_REQ O Communication request to system computer

48~50 KR2~KR4 I Key return signal input 2~4

51 VFD_ON O VDD1 control for VFD Operat with system computer’s PON and PN_SC_CON, “H” : on

52~64 NC O Not used (OPEN)

GX -401EF2

DISASSEMBLY FOR REPAIR

● How to Remove the Holder

Plugging the minus small size screwdriver to the holder toward

it causes it toward B.

Heat sink

Holder (J19-5161-05)

Top plate

Set up the screw point

Heat sink

Minus small size screwdriver

1. How to enter the test mode is while pressing on [MUTE] and [PRESET1] keys, press the [POWER] key .

2. Set FM mode press the [BAND] key.

● Setting of FM ANRC

Receive condition 98.1MHz, an electric field intensity are EMF 41dBµV and Mod OFF. Complete on condition that show “ADJ OK” when pressing on [PRESET1] and [PRESET6] keys .

● Separation adjustment of K2I NARROW

Adjustment at NARROW of manual mode. This manual mode (NARROW) setting on condition that “REP” lighting (switch [PRESET5]) and “RDM” not lighting (switch [PRESET6]). VR11 (FS) adjust the maximum separation when FM stereo standard input (98.1MHz, an electric field intensity are EMF 66dBµV and 1kHz).

● Setting of MW and LW seek stop level

Receive condition 999kHz, an electric field intensity are EMF 35dBµV and Mod OFF. Complete on condition that show “ADJ OK” when pressing on [PRESET1] and [PRESET6] keys . Releasing the test mode when BU OFF or POWER OFF.

Holder

Antenna cord

Rear side

ADJUSTMENT

● Adjument of Dolby level

Playback the TCC-130 (Dolby level tape). Test pin level at 300mVrms adjustment VR1 (TL) and VR2 (TR).

● How to measurement FM WAIDE/NARROW

1. How to enter the test mode is while pressing on [MUTE] and [PRESET1] keys, press the [POWER] key .

2. Set FM mode press the [BAND] key.

3. Measurement on condition that WIDE/NERROW are manual mode. Manual mode when “REP” lighting in testmode.

4. Change the “manual mode” and “automatic mode” on con- dition that press the [PRESET5] key in test mode. Manual mode : “REP” lights Automatic mode : “REP” put out the lights

5. Change the “WIDE” and “NARROW” setting the manual mode after that press the [PRESET6] key. WIDE : “RDM” lights NARROW : “RDM” put out the lights

ON OFF [PRESET5] “REP” Manual Automatic [PRESET6] “RDM” WIDE NARROW

A B C D E F G H I J

PC BOARD (COMPONENT SIDE VIEW) PC BOARD (FOIL SIDE VIEW)

CD PLAYER UNIT CD PLAYER UNIT

X32-5240-01 (J74-1249-02)

R234

R233

C35

C24

R218

C26

C28

R34

R36 R37

C85 R54 C46

R52

R202

C25

R38

C89

CP1

CP2

C17

R32

C21

C23

C15

C13

R18

R16

R15

C14

SLED-/EJECT

SLED+/LOAD

TRK+

TRK-

X32-5240-01 (J74-1249-02)

IOP-

GND

R46

221

CN2

CN1

FCS+

FCSD GND

/MUTER

/MRST

LO/EJ

R47

BU 5V

/MUTEL

/MSTOP

MOTOR

VCC

DATA

Vref

R3 D

LOS

ARF

A +8V

C20

D OUT

12EJE

/CLK

8EJE

IOP+

R21

C19

R10

Lch

GND

IC1

R11

R12

R20

C18 R19

PON

C16

R17

1732

161

C12

SPDL-

SPDL+

GCTL

C11 C10

FBAL

TBAL

VDET

Vref

TRCRS

25 1

C29

51 75

DQS

ECS

TVD

ECM

KICK

TRD

TRV

FOD

RFENV

IC2

C33

LDON

/RFDET

100

R214

BDO

OFT

LDCNT

C55

R49

R125

R121

C77

R117

C71

R118

C72

R122

IC6

C78

R126

R107

C51

R108

C79

C80

R71

R82

C41

R74 R75

R73

S 7.5V

S GND

R40

A GND

LOE/LIM

14 1

DRVMUTE

IC4

Rch

C44 R79

R76 C40

R81 R80

2815

C42 R84

R70 C39

IC5

C70

C69

GIO

R102

R103 R104

C68

C67

R101

CD PLAYER UNIT (X32-5240-01)

Ref. No.

IC Q

Address

65B

Refer to the schematic diagram for the values of resistors and capacitors.

CD PLAYER UNIT (X32-5240-01)

Ref. No.

IC Q

Address

12H 23I 45H 55I

13G

Ref. No.

IC Q

23G 34I 43G 53H

Address

109

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