CASSETTE RECEIVER
KRC-16A/G/YA/YG
SERVICE MANUAL
© 2001-10 PRINTED IN KOREA
B51-7857-00 (K) 2161
KRC-191A/G/YA/YG
KRC-265LA/LG/RG
KRC-26A/G/YA/YG
KRC-291A/G/YA/YG
KRC-265RG
KRC-16A/G/YA/YG (E)
KRC-191A/G/YA/YG (E)
KRC-265RG (M)
45W x 4
KRC-265L
45W x 4
AUTO
AME
KRC-291
45W x 4
KRC-26
45W x 4
KRC-191
45W x 4
T.CALL
KRC-16
45W x 4
T.CALL
KRC-26A/G/YA/YG (E)
KRC-291A/G/YA/YG (E)
KRC-265LA/LG (M)
DC1
242
201
262
261
216x2
263
The following reference numbers with accessory parts are the same reference numbers
used on EXPLODED VIEW and PARTS LIST.
KRC-16,191,265L/R,26,291
2
BLOCK
DIAGRAM
IC1
KEY
PAN 5V
MUTE
B.U. DET.
B.U.
ACC
P-CONT.
MUTE
PRE
POWER IC
EQ. AMP.
CH ISO AMP
NC,MPX
E-VOL.
CD/MD
CHANGER
FRONT Lch
FRONT Rch
REAR Lch
REAR Rch
J2
LCD DRIVER
LCD
ME1
MAIN
TAPE MECHA.
IC5
Lch
Rch
PRE OUT
IC2
IC4
IC3
SP OUT
REAR
J4
PAN IN SW
ACC DET.
P-CONT.
J2
J5
IC1
F/E
J1
FM+B
Q201
AM+B
Q203
AM BPF
FM BPF
C154,R206
C153,R207
Q320
Q450,451
Q49
Q50
Q350,351,370
Q53
SW 5V
Q54-57
8V
Q58-61
ILLUMI.
B.U. 5V
Q51,52
SYSTEM u-COM
S1
S2
S3
RST SW
Q301
D1-15
PL1,2
ANT.
TEL MUTE
DECODER
RDS
IC7
Q501,502
MP SW
40W
RST IC
RST
IC6
ED1
FM ANT
AM ANT
RF GND
FM+B
AM+B
OSC GND
OSC GND
OSC GND
VT
PLL +B
IFC OUT
SDA
SCL
DIG GND
IF1+B
IF1 GND
S-METER
IF2 GND
SD
FM+B
P.ON
ACC DET
B.U. DET
SCL
MUTE
SDA
P CON
P
ANEL
RESET
L
CLK
L
D
ATA
S
L
D
ATA
L
FWD/REV
MOT
OR
CH
CON
D
ATA
H
D
ATA
C
REQ
H
REQ
C
CH
CLK
Rch
COM
Lch
MP IN
AM
MPX
OUT RR
OUT LR
OUT RF
Rch
LEVEL
SCL
SDA
OUT LF
Rch
STBY
MUTE
Rch
Lch
T-MUTE
FWD
REV
B.U.5V
8V
B.U.
CH
RST
S
MUTE
8
5
10
B.U.5V
AM+B
VDD 5V
P
ACK
IN
L
RES
PHONE
CH
MUTE
BEEP
SVR
AMP. STBY
SVR
AC GND (BEEP)
Lch
Lch
Rch
Lch
1200mV
TAPE :1681mV
CD/MD-CH :3529mV
AM :772mV
FM :1339mV
8V
RF GND
OSC GND
IF2 +B
AUDIO OUT
8V
S-METER
SD
PLL-SCL
PLL-SDA
M1
PLAY
HEAD
L/R
55.6mV
B.U.5V
SW 5V
8V
B.U.5V
AM: 170mV
FM: 213mV
TAPE
PACK IN
(FF/REW)
AMP. MUTE
FF/REW
B.U.5V
R QUAL
IF COUNT
R CLK
R DATA
SW 5V
MP OUT
QUAL
AFC
NOISE
B.U.5V
ILL
L
C
E
(X16)
M
KRC-16,191,265L/R,26,291 (E,E,M,E,E)
A1
TEL DET
D380
5V
R205
KRC-16,191,265L/R,26,291
3
COMPONENT DESCRIPTION
REF No.
FUNCTION
OPERATION
IC1
SYSTEM µ-COM
Controls the unit.
IC2
E-VOLUME
Controls the volume and selects source.
IC3
MUTE LOGIC
Controls the mute output.
IC4
POWER AMPLIFIER
For the speaker output.
IC5
EQUALIZER AMPLIFIER
For the cassette tape's signal.
IC6
RESET
Resets the power.
IC7
RDS DECODER
Decodes the radio data.
Q49
ACC DETECTION SW
Outputs "H" during the ACC off.
Q50
BACK-UP DETECTION SW
Outputs "H" when the back-up voltage is under 9.2V.
Q51,52
BACK-UP 5V DRIVER
Works when back-up current exists.
Q53
P.ON 5V SW
Works during the power on.
Q54,55
8V SW
Works during the power on.
Q56,57
8V DRIVER
Works during the power on.
Q58,59
ILLUMI +B SW
Works during the power on.
Q60,61
ILLUMI +B DRIVER
Works during the power on.
Q150
E-VOL MUTE SW
Works when the back-up current is detected
or the changer mute works or system µ-com mute works.
Q151
SVR FORCED DISCHARGE SW
Works when the amplifier mute works.
Q153
PRE OUT MUTE SW
Works when the back-up current is detected
or the changer mute works or system µ-com mute works.
Q201
FM +B SW
Works during FM mode.
Q203
AM +B SW
Works during AM mode.
Q260
MOTOR +B SW
Works during the tape mode.
Q261
MOTOR +B DRIVER
Works when Q206 works.
Q301
CD-CH RESET SW
Works when the power is reset and the reset SW works.
Q320
PANEL 5V SW
Works when the back-up current exists and the panel
is attached on the unit.
Q350
P.CON DRIVER SW
Does not work during the power off and the ALL OFF.
Q351
P.CON PROTECTION SW
Works when the P.CON is short-circuited on the GND.
Q352
P.CON PROTECTION INHIBIT SW
Inhibits the protection SW in a moment during the P.CON on.
Q353
P.CON DRIVER SW
Does not work during the power off and the ALL OFF.
Q450,451
PRE OUT MUTE SW
Works when the back-up current is detected
or the changer mute works or system µ-com mute works.
Q500
AUDIO OUTPUT BUFFER
For RDS decoder.
Q501,502
AFC TIME CONSTANT SW
Works during receiving FM signal.
Q503
NOISE BUFFER
For noise level detection.
SYNTHESIZER UNIT (X14-687x-xx)
KRC-16,191,265L/R,26,291
4
MICROCOMPUTER'S TERMINAL DESCRIPTION
PORT No. PORT NAME
I/O
FUNCTION
OPERATING CONDITION
1
PANEL
I
Panel detection.
"L" : Panel exists.
2
L CE
O
LCD driver chip enable.
-
3
L RES
O
LCD driver reset.
-
4
AVSS
-
GND.
-
5
R DATA
I
RDS data.
-
6
R QUAL
I
RDS receiving.
-
7
AVREF 1
-
Reference voltage.
-
8
IC2 SEL 1
I
Selector.
"L" : Normally.
9
IC2 SEL 0
I
Selector.
"L" : Normally.
10
-
-
-
-
11
L DATA L
I
LCD driver communication data.
-
12
L DATA S
O
LCD driver communication data.
-
13
L CLK
O
LCD driver communication clock.
-
14,15
-
-
-
-
16
DATA C
I
Changer communication data.
-
17
DATA H
O
Changer communication data.
-
18
CH CLK
I
Changer communication clock.
-
19-26
-
-
-
-
27
MOTOR
O
Cassette tape motor SW.
-
28
FF/REW
I
Cassette tape FF/REW detection.
"L" : FF or REW works.
29-31
-
-
-
-
32
SD
I
Signal detection.
"H" : Signal exists.
"L" : Signal does not exist.
33
VSS 1
-
GND.
-
34
-
-
-
-
35
PLL CLK
O
Front-end communication clock.
-
36
PLL DATA
I/O
Front-end communication data.
-
37
AM +B
O
AM power supply SW.
-
38
FM +B
O
FM power supply SW.
-
39
IC2 DATA
I/O
E-volume communication data.
-
40
IC2 CLK
O
E-volume communication clock.
-
(X14-) IC1 : µ-COM
KRC-16,191,265L/R,26,291
5
MICROCOMPUTER'S TERMINAL DESCRIPTION
PORT No. PORT NAME
I/O
FUNCTION
OPERATING CONDITION
41
AFC
O
FM noise detection / Time constant SW.
-
42
MUTE
O
Mute control.
-
43
AMP MUTE
O
Power amplifier mute.
-
44
-
-
-
-
45
CH CNT
O
Changer control.
-
46
REQ H
O
Changer request.
-
47
-
-
-
-
48
SVR
O
SVR control.
-
49
AMP STBY
O
Power amplifier stand-by.
-
50
BEEP
O
Buzzer signal output.
-
51,52
-
-
-
-
53
P.CONT
O
Power control SW.
-
54
ACC DET
I
ACC detection.
-
55
B.U. DET
I
Back-up detection.
-
56
P.ON
O
Power SW.
-
57
ILLUMI
O
Illumination SW.
-
58
FWD/REV
I
Cassette mechanism FWD/REV detection.
-
59
-
-
-
-
60
RESET
I
System reset signal input.
-
61
SEL 1
I
Destination SW.
-
62
R CLK
I
RDS clock.
-
63
REQ C
I
Changer request.
-
64
PACK IN
I
Cassette tape pack-in detection.
-
65
KEY-REQ
I
Key signal input detection.
-
66
SEL 0
I
Destination SW.
-
67
VSS 0
-
GND.
-
68
VDD 1
-
5V power supply.
-
69
X2
-
Main system clock.
-
70
X1
I
Main system clock.
-
71
IC
-
GND.
-
72
-
-
-
-
73
XT1
-
5V power supply.
-
74
VDD 0
-
5V power supply.
-
75
AVREF 0
I
A/D converter reference voltage.
-
76
S METER
I
S-meter detection.
"H" : S-meter exists.
"L" : S-meter does not exist.
77
PHONE
I
-
Navigation mute : 2.5V or more.
Telephone mute : 1V or less.
78
NOISE
I
FM noise detection.
-
79
AV CONT
O
A/D converter reference voltage.
-
80
-
-
-
-
(X14-) IC1 : µ-COM