CASSETTE RECEIVER
KRC-309S/389/389W
SERVICE MANUAL
© 2001-1 PRINTED IN KOREA
B51-7733-00 (K) 1733
KRC-409/479
KRC-489/489G
KRC-309S (K)
KRC-309S
CD MD-Changer Control
45W x 4
CRSC
KRC-389
CD MD-Changer Control
45W x 4
CRSC
KRC-389/389W (M)
KRC-409 (K)
KRC-409
CD MD-Changer Control
45W x 4
CRSC
KRC-479 (M)
KRC-479
CD MD-Changer Control
45W x 4
CRSC
KRC-489/489G (M)
MECHANISM EXTENSION CORD
W05-0477-00 (7P)
W05-0609-00 (10P)
KRC-489
CD MD-Changer Control
45W x 4
CRSC
RC1
763x2
262
261
242
223x2
DC1
201
246
The following reference numbers with accessory parts are the same reference numbers
used on EXPLODED VIEW and PARTS LIST.
40%
(X13)
(X14)
M
M
KRC-309S/389/389W
(K/M/M)
KRC-409/479,489/489G
(K/M,M/M)
RX-380
(J)
F/E
SW5V
B.U.14V
B.U.5V
B.U.14V
FM
ANT
AM
ANT
RF
GND
FM+B
AM+B
OSC
GND
OSC
GND
OSC
GND
OSC
GND
OSC
GND
PLL+B
PLL-DA
T
A
VT
IFC
OUT
PLL-CLK
VDD
5V
IF2+B
IF2
GND
DIG
GND
IF1
GND
S-METER
IF1+B
SD
AUDIO
OUT
PLL-DA
T
A
SD
S-METER
SUB+
SUB-
EN2
ACC-DET
EN1
SCL
MUTE
SDA
EN3
SW5
PC-DET
P
A-DET
PAN
EL
HOLD
L-CLK
L-CE
L-DAT
AS
L-DAT
AL
MUSIC
DOLBY
MTL
EQ-MUTE
MS-CONT
MUSIC
DOLBY
MTL
EQ-MUTE
MS-CONT
DSI
FWD/REV
PA
CKIN
M-STBY
CHCON
DAT
AH
DAT
AC
REQH
REQC
CHCLK
Rch
COM
Lch
MP
IN
AM
MPX
OUT
RR
SW5V
OUT
LR
OUT
RF
LEVEL
SCL
SDA
OUT
LF
SVR
MUTE
EN1
EN2
EN3
P
.ANT
P
,CON
ILLUM
B.U.5V
AM+B
AUDIO
FM+B
FM+B
AM+B
AUDIO
8V
B.U.5V
Rch
Lch
P
ACK
T
-END
M-STBY
T
-MODE
FWD
REV
B.U.5V
AUDIO
8V
B.U.14V
CHRST
SMUTE
FM+B
AM+B
AUDIO
8V
AUDIO
8V
MAIN
M
MOT
OR
B.U.14V
SW5V
8
4
10
40
IN
PLA
Y
HEAD
B.U.5V
PLL-CLK
T-MODE
T-END
B.U.5V
REMO
SW5V
BU-DET
P-STBY
SVR
P-MUTE
CHMUTE
STBY
CD
L/R
CD
L/R
TA
PEL/R
1200mV
400mV
170mV
340mV
T
A
PE
:1719mV
CD-CH
:3424mV
AM
:550mV
FM
:1727mV
T
APE
:1780mV
CD-CH
:3546mV
AM
:570mV
FM
:1789mV
AUDIO
8V
T
APE
L/R
SW5
SYSTEM
u-COM
KEY
P
AN
5V
MUTE
B.U.
DET
SURGE-DET
P
A
-DET
PC-DET
B.U.
ACC
P-CONT
ANT
-CON
MUTE
DC
CONNECT
OR
PRE
POWER
IC
IC6
EQ
AMP
CD
ISO
AMP
NC,MPX
IC2
E-VOL.
CD/MD
CHANGER
FRONT
Lch
FRONT
Rch
REAR
Lch
REAR
Rch
REGULA
T
O
R
LCD
DRIVER
LCD
T
APE
MECHA
MAIN
SUB
IC5
F-Lch
F-Rch
R-Lch
R-Rch
PRE
OUT
SP
OUT
SUB
M
MOT
OR
5V
AV
R
CDS-522
DSI
REMO
RST
SW
P
AN
IN
SW
ACC
DET
J2
VOL
T
AGE
DRIVER
AMP
SVR
PC-DET
P
A
-DET
MUTE
THERMO
PROTECTION
LC72366
KRC-309S/389/389W,409/479,489/489G
2
BLOCK DIAGRAM
KRC-309S/389/389W,409/479,489/489G
3
COMPONENT DESCRIPTION
REF
FUNCTION
OPERATION
No.
IC1
SYSTEM µ-COM
Controls FM/AM tuner, the changer, cassette mechanism,
volume and tone.
IC2
E-VOLUME
Controls the source, volume, tone and FM multiplex detector.
IC4
POWER AMPLIFIER
Amplifies the front L/R and the rear L/R to 45W maximum.
IC5
EQUALIZER AMPLIFIER
Equalizes the tape sound (120uSec.).
IC6
SUB MOTOR DRIVER
Controls the sub motor.
IC7
AVR
B.U.:5V, AUD:8V, FM+B:8V, AM+B:8V
IC10
MUTE CONTROL LOGIC Controls logic.
Output becomes "L" when the back-up voltage becomes more than 9V.
Q10
BACK-UP DETECTION
Output becomes "H" when the back-up voltage becomes less than 9V
(momentary power down).
Output becomes "L" when the back-up voltage becomes more then 18V
Q11
SERGE DETECTION
(Momentary power down). Output becomes "H" when the back-up
voltage becomes less than 18V.
Q41
PRE MUTE DRIVER
When input becomes "L", output becomes "H" (Preout mute).
Q50
5V SW
Outputs 5V to the SW5V power supply when input becomes "L".
SW5V power supply line is cut off when the input becomes "H".
Q51
POWER ANTENNA
Output becomes "H" when P-ANT output is short-circuited (P-ANT OFF).
DETECTION
Output becomes "L" when FM/AM signal does not exist.
Q52
P.CON. DETECTION
Output becomes "H" when P.CON output is short-circuited (P.CON OFF).
Q190
PANEL SW
Outputs 5V to the panel VDD line when panel is attached.
Panel VDD line is cut off when panel is taken out.
Q191
DSI DRIVER
DSI lights when input becomes "L". DSI turns off when input becomes
"H".DSI turns on and off when panel is taken off.
Q221-224 PRE MUTE
Works when input becomes "H". Being cancelled when input
becomes "L".
Q251
SVR
"L" when input becomes "H".
Q501
SUB MOTOR AVR
Outputs 7.3V when AUD8V exists. Output does not exist when AUD8V
does not exist.
Q551
MAIN MOTOR SW
Outputs 14V when input becomes "L" (Main motor drives).
Q552
MAIN MOTOR SW
Output becomes "H" when input becomes "L".
REF.
FUNCTION
OPERATION
No.
IC1
LCD DRIVER
Scans LCD display control key.
IC2
REMOTE SENSOR
Sensors remote controller signal.
Q1
KEY SCAN SW
Scans key after receiving imitative key input signal.
SYNTHESIZER UNIT (X14-639x-xx)
SWITCH UNIT (X13-986x-xx)
KRC-309S/389/389W,409/479,489/489G
4
MICROCOMPUTER'S TERMINAL DESCRIPTION
PORT
PORT NAME
I/O
FUNCTION
OPERATING CONDITION
No.
1
X IN
I
Clock : 4.5MHz.
2
GND
-
GND.
3
L-DATA L
I
LCD driver data.
4
L-DATA S
O
LCD driver data.
5
L-CLK
O
LCD driver clock.
6
L-CE
O
LCD driver chip enable.
7
PANEL
I
Panel detection.
8
PLL-DATA
I/O Tuner data.
9
PLL-CLK
O
Tuner clock.
10
SD
I
Tuner band muting.
11
CH-DATA C
I
5-line CD-CH communication data.
12
CH-DATA H
O
5-line CD-CH communication data.
13
CH-CLK
I/O 5-line CD-CH communication clock.
14
CH-REQ C
I
5-line CD-CH communication request.
15
MOTOR
O
Cassette mechanism main motor.
16-20
-
-
-
21
CH-CON
O
5-line CD-CH communication control.
22
CH-REQ H
O
5-line CD-CH communication request.
23
MUTE
O
Muting.
24
IC2-SCL
O
IC2 clock.
25,26
-
-
-
27
IC2 TYPE 0
I
Model discrimination.
28
-
-
-
29
TYPE 1
I
destination discrimination.
30
TYPE 0
I
destination discrimination.
31
VDD
-
Power supply.
32
IC2-SDA
I/O IC2 data.
33
SW 5V
O
SW 5V control.
34
P-MUTE
O
Power IC muting.
35
P-STBY
O
Power IC stand-by.
36
SVR
O
Power IC discharge control.
37
EN1
O
Power supply IC contol.
38
EN3-1
O
Power supply IC contol.
39
EN3-0
O
Power supply IC contol.
40
EN2-1
O
Power supply IC contol.
(X14-) IC1 : µ-COM
KRC-309S/389/389W,409/479,489/489G
5
MICROCOMPUTER'S TERMINAL DESCRIPTION
PORT
PORT NAME
I/O
FUNCTION
OPERATING CONDITION
No.
41
EN2-0
O
Power supply IC control.
42
-
-
-
43
MS-CONT
O
Tape signal sensitivity switch.
44
BEEP
O
Beep.
45
BU-DET
I
Back-up detection.
46
P.CON-DET
I
Power control short-circuited detection.
47
P.ANT-DET
I
Power antenna short-circuited detection.
48
MUSIC
I
Tape signal detection.
49
METAL
O
Normal/Metal tape switch.
50
DOLBY
O
Dolby switch.
51
EQ-MUTE
O
Tape equalizer muting.
52
FWD/REV
I
Cassette mechanism running direction.
53,54
-
-
-
55
PACK-IN
I
Cassette mechanism pack-in.
56
REMOTE
I
Remote signal shape.
57
-
-
-
58
DSI
O
Disable System Indicator.
59
SUB+
O
Cassette mechanism sub motor.
60
SUB-
O
Cassette mechanism sub motor.
61,62
-
-
-
63
IC2 TYPE 1
I
Model switching.
64
T-MODE
I
Cassette mechanism mode pulse.
65
ACC-DET
I
ACC detection.
66
S-METER
I
Tuner signal meter.
67
HOLD
I
Clock stop mode.
68
VDD
-
VDD.
69
M-STBY
I
Cassette mechanis stand-by.
70
T-END
I
Cassette mechanism end.
71,72
-
-
-
73
VDD
-
VDD.
74-76
GND
-
GND.
77,78
-
-
-
79
GND
-
GND.
80
X OUT
O
Clock 4.5MHz.
(X14-) IC1 : µ-COM