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CASSETTE RECEIVER
KRC-391/391Y
KRC-36/36Y/30Y
SERVICE MANUAL
● KRC-391
© 2001-10 PRINTED IN JAPAN
B51-7853-00 (S) 1929
MECHANISM EXTENSION CORD
W05-0477-00 (7P)
W05-0609-00 (10P)
Knob(VOL)
(K25-1395-03)
SRC
OFF
Knob(SRC)
(K24-3820-04)
∗ Refer to the PARTS LIST
Plastic cabinet assy
(A02-1486-13)
∗ Panel assy
(A64-2538-02)
KRC-391
LOUD SCRL SCAN REP T.CALL M.RDMB.S/RDM MENU TI VOL ADJCLK
Knob(1-6)
(K25-1392-03)
Cassette lid
(A53-1687-03)
45Wx4
∗ Front glass
(B10-4127-01)
Knob(FM,AM)
(K25-1393-03)
DISC
AUD
Knob(AUD)
(K24-3821-04)
Mounting hardware assy
(J21-9641-13)
Lever
(D10-4589-04)
DC cord
(E30-4792-05)
Antenna adaptor
(T90-0523-05)
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2
FM ANT
AM ANT
RF GND
FM+B
AM+B
AM LO/DX
FM LO/DX
IF SELECT
RDS OUT
FM SD OUT
REQUEST
K2I-VTH
VCO-GND
FSD OUT
FM DET OUT
AM DET OUT
IF GND
COMMON+B
P-ON 5V
DIG GND
PLL DATA
PLL CLK
PLL CE
HI UP ADJ
FM+B
AM+B
A8V
SW5V
LO/DX
SD
S-METER
PLL-DATA
PLL-CE
SW5V
ACC-DET
BU-DET
SCL
MUTE
SDA
EN1
EN2
EN3
PANEL
RESET
DSI
CH MUTE
NOISE
DATA H
DATA C
REQ H
REQ C
CH RST
CH CON
CH CLK
Rch
COM
Lch
TAPE L/R
MP IN
AFS
QUAL
AM
MPX
OUT RR
OUT LR
OUT RF
LEVEL
SCL
SW5V
SDA
SCL
SDA
OUT LF
STBY
MUTE
SMUTE
5
10
BU5V
AFS
R QUAL
R CLK
R DATA
BU5V
REMO
SW5V
GREEN
RED
BU5V
PHONE
BEEP
SVR
P-MUTE
P-STBY
SVR
AC GND(BEEP)
TAPE L/R
PLL-CLK
SW5V
L-RES
L-CLK
L-DATA S
L-DATA L
MUSIC
EQ-MUTE
MS-CONT
MUSIC
EQ-MUTE
MS-CONT
FWD/REV
PACK IN
M-STBY
T-MODE
T-END
L-CE
340mV
SUB+
SUB-
Rch
Lch
PACK
T-END
M-STBY
T-MODE
FWD
REV
AUDIO
8V
MOTOR
BU14V
SW5V
IN
PLAY HEAD
SW5V
BU14V
BU5V
BU14V
EN1
EN2
EN3
P,CON
ILLUM
B.U.5V
AM+B
AUDIO
FM+BFM+B
AM+B
AUDIO 8V
AUDIO 8V
AUDIO 8V
BU5V
SW5V
TAPE
CD-CH
AM
FM
: 1719mV
: 3424mV
: 550mV
: 1727mV
TAPE
CD-CH
AM
FM
: 1786mV
: 3546mV
: 850mV
: 1345mV
AM : 160mV
FM : 213mV
CD L/R
1200mV
BU14V
CD L/R
8
RDS
ANT.
DECODER
SYSTEM u-COM
KEY
PAN 5V
MUTE
E2PROM
EQ AMP
CD ISO AMP
E-VOL
LCD DRIVER
LCD
DSI
REMO
RST SWPAN IN SW
GREEN
RED or
RST IC
TEL DET TEL MUTE
DRIVER
MAIN
SUB
AVR
SW5
B.U. DET
SURGE-DET
B.U.
ACC
P-CONT
DC CONNECTOR
REGULATOR
ACC DET
J2
VOLTAGE
MUTE
PRE
R-Lch
R-Rch
AMP
SVR
MUTE
THERMO
PROTECTION
FRONT Lch
FRONT Rch
REAR Lch
REAR Rch
IC4
J4
POWER IC
TDA7386
CD/MD
CHANGER
SP OUT
J5
PRE OUT
IC10
SUB MOTOR
DRIVER
MOTOR
DRIVER
IC1
IC2
IC12
IC9
IC2
IC1
IC11
IC7
IC8
Q2,3
IC6
TUNER
(X16)
(X14)
MM
TAPE MECHA
KRC-391/Y,36/Y,30Y
BLOCK DIAGRAM
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KRC-391/Y,36/Y,30Y
COMPONENT DESCRIPTION
● SYNTHESIZER UNIT(X14-6892/9002-XX)
REF.No. FUNCTION OPERATION
IC1 SYSTEM µ-COM
IC2 E-VOLUME
IC4 POWER AMPLIFIER Speaker output
IC6 RDS DECODER
IC7 POWER IC
IC8 MUTE CONTROL LOGIC 3 input NOR gate x 3
IC9 EQUALIZER AMPLIFIER For full logical cassette mechanism control
IC10 SUB MOTOR DRIVER For full logical cassette mechanism sub motor driver
IC11 RESET IC Detection voltage below 3.0V
IC12 EEPROM
Q1 P.CON.DETECTION Detects P.CON voltage.
Q10 BACK-UP DETECTION Detects the back-up voltage.
Q11 SERGE DETECTION Detects serge voltage.
Q20 ACC DETECTION Detects ACC voltage.
Q40 PREOUT MUTE DRIVER Mutes when the base terminal voltage level becomes "L".
Q50 5V SW Works when the base terminal voltage level becomes "L".
Q101 DSI SW LED for DSI works when the base terminal voltage level becomes "H".
Q151 PANEL 5V SW Works when the base terminal voltage level becomes "L". Supplies VDD to panel.
Q201 NOISE DETECTION Detects noise.
Q221-224
Q251 POWER IC SVR SW Discharges the capacitor's voltage of SVR terminal after the base terminal voltage
Q301 LOCAL SEEK SW Changes to the local seeking after the base terminal voltage becomes "H".
Q501 MOTOR DRIVER AVR Works when the base terminal voltage becomes "H". Supplies the power to the motor
Q551 MAIN MOTOR SW Works when the base terminal voltage becomes "L".
Q552 MAIN MOTOR SW Works when the base terminal voltage becomes "H".
PREOUT MUTE Mutes when the base terminal voltage level becomes "H".
becomes "H".
driver.
● SWITCH UNIT(X16-1532/1722-XX)
REF.No. FUNCTION OPERATION
IC1 LCD DRIVER
IC2 REMOTE SENSOR
Q1 KEY SCAN SW Receives key signal when the base terminal voltage becomes "L".
Q2 KEY ILLUMINATION SW Key illumination color becomes green when the base terminal voltage becomes "H".
Q3 KEY ILLUMINATION SW Key illumination color becomes red when the base terminal voltage becomes "H".
3