Kenwood KRC-20SA Service Manual page 10

A B
WHT GRN
1
FL+ 8 16 RL+
WHT/BLK GRN/BLK
FL- 7 15 RL-
GRY/BLK VIOL/BLK
FR- 6 14 RR-
GRY VIOL
FR+ 5 13 RR+
P CON
BLU/WHT
ANT CON
4 12
BLU/WHT
3 11
RED
2 10
BLK YEL
1 9
2
2 4 6 8
A
B.U
1 3 5 7
P.CON
2 4 6 8
B
1 3 5 7
DC CORD
(E30-4959)
IC1 : LC72366-9592 Q50,52,57,61 : 2SC2412K or
IC2 : TDA7461ND 2SD601A
IC3 : HD74HC27FP Q51,261 : 2SB1443
IC4 : TDA7384A Q53 : DTA114YK or
3
IC5 : LA3161 UN2114 or
KRA107S
∗
D50 : S2V20 A or Q54,58 : DTC144EK or
1N5393G-M6 UN2213 or
D51 : MA4068(N)-M or KRC104S
HZS7A3L Q55,59,352 : DTA124EK or
D52 : MA4051-L UN2112 or
D53,260,261,350,351,370,371 KRA103S
: AM01Z or Q56,60 : 2SA2057 or
2SB1548(P) or
ERA15-01 or
DSM1SD2 2SB1565(E,F) or
D54 : MA4056(N)-M 2SB1655(E,F)
D55 : MA4091(N)-L Q150,200,202 : DTC124EK or
D56 : MA4110-L UN2212 or
D100,150-152,352 KRC103S
: 1SS133 Q151,260,353,371 : DTC114YK or
D200 : MA4051(N)-M UN2214 or
KRC107S
Q201,203,350,370 : 2SB1277(Q,R)
4 Q301 : DTA144EK or
UN2113
SIGNAL LINE
Q320,351 : 2SA1037K
GND LINE
+B B LINE
Q58
Q58,59
ILLUMINATION
+B SW
Q59
14.4V
BU
Q60
D56
5
+B 2
Q61
10.2V
Q60,61
ILLUMINATION
+B DRIVER
WH1
T.MUTE 6 28
GND 5
D260 13.6V
MOT GND 4
Q261
D261
13.6V
MOT +B 3 +B +B
Q260,261
MOTOR
6
+B SW
10K
15
47K
PACK IN 2
Q260
GND 1
27
CAUTION : For continued safety, replace safety critical components only with
manufacturer's recommended parts (refer to parts list).
Indicates safety critical components. To reduce the risk of electric shock, leak-
!
age-current or resistance measurements shall be carried out (exposed parts are
acceptably insulated from the supply circuit) before the appliance is returned to
7
the customer.
• DC voltages are as measured with a high impedance voltmeter. Values may
vary slightly due to variations between individual instruments or/and units.
C D
F1 (10A)
J2 SYNTHESIZER UNIT (X14-6852-71)
16 15 14 13 12 11 10 9
8 7 6 5 4 3 2 1
IC4
POWER IC
R50
D50
3.3K
0V
1/2W
C50
3300u16
14.4V
BU
+
BU BU BU
R370
BACK-UP DETECTION
4.7K
(MOMENTARY POWER
DOWN DETECTION)
D370 Q370,371
D52
SW
ANT-CON.
SW
C52 R54 R52
D51
Q371 Q370 0.01 10K 33K
R371
1K R57 Q50
1/2W 43K
R373 R372
1K 22K 61 62
Q51,52
1/2W
BACK-UP
40
C53
5V AVR
100u16
R350
4.7K
+
R58
D54
22K
C54
R351 Q51
0.01
1K
Q350
Q350
1/2W
P-CON.
C350
DRIVER
C55
3.3u25 Q52
10u10
+
+
P-CON.
SW
Q351
C56
100u6.3
C351
Q353 +
Q53
0.068 P.ON
47K
5V AVR
41
Q352
10K
Q351
C352
D352
0.1u50 P-CON.
+ PROTECTION SW
14.4V
BU
Q352
P-CON.
Q151
PROTECTION
INHIBIT SW
BU
P5V P5V
+5V +5V +5V
44
C101
0.01
41
41 SW5V
42
5V
ILL
0V
43
5V
5V
0V
0V 44
BEEP
0V
45
46
5V
47 0V
R110 47K 48
ROLL OFF 0V
R108 47K 49
NOISE CANCELLER
R120 47K 50
SEL1
R122 47K 51
SEL2 0V or 5.0V
52
IC1
SEL3
53
EQ MUTE SYSTEM MI-COM
R132 54
5V
FWD/REV 0V
100K 55
R103
2.2M 56
REMO
57
58
R129 22K
59
D100
4V
60
0V
61
5V
61 ACC DET
62 5V 0V
5V
62 B.U. DET 0V 0V
R138
63
63 S METER
22K 64
PANEL
4V
0V 0V
0V
+5V
2SB1565
E F
BU BU
+
R156
180K
C159
100u10
5V
+ 0V
+
C160
TH1 D151
10u16
+
+5V
IC3
1 14
5.0V
VDD
5V
13
0V
Q151
2
IC3
5V
MUTE 0V
3
LOGIC
4
12
11
5
10
6
9
5V
0V
5V
0V
+5V R160 47K 7
8
GND
SVR DISCHARGE SW
R159 100K
0V
BU BU
P5V
R125
5.0V 47K
+5V
2
+B
R127
47K
R126
47K
RESET
Q301
24
23
22
21
20
5.0V
5V
19
R321 R320
18
5V 27K 47K
0V
17
16
5V Q320
SCL
Q320
15 PANEL 5V
MOTOR 5.0V
SW
14
13
CH CLK 67
12
DATA H
11
DATA C
5V
10 R116 4.7K
C320
0V SD 10
47u6.3
9 R119 2.2K
PLL CLK
9
+
R118 2.2K
8
PLL DATA 8
R114 22K
R105
7 1K
SDA 7
R131 10K
6
6
L CE
5V
5
0V L CLK 5 11 9 7 5 3
4
L DATA S 4 12 10 8 6 4
J3
3
3
L DATA L
2 0V
GND
1 C102
XIN
22P
C103
22P
DTA114EK DTC124E 2SB1548
DTA114YK K
DTA124EK DTC144E
DTA144EK K
DTC114YK KRC103S
G H
8.2V
FM+B SW
22K
26
22K
Q200
25
L3 4.7uH
+B
C150 Q150
47u10
+
C151
0.01
IC2
Q150
ELECTRIC
VOLUME
0V
8.2V
MUTE SW
5V
3.4V 0V
5V
0V
IC2
E-VOL. &
N.C. MPX
14.4V
C157
150P
C156
0.033
54
R65
2.2 1/2W 14.2V 8.2V
BU +B
Q56
R66
2.2 1/2W
COM+B
AVR
Q57
R63 R64
Q55
1K 1K
C251
0.047
Q54
Q54,55
47K
COM
+ +
+B SW
47K
C3
47u6.3
C6
100P
IC5
EQUALIZER
AMPLIFIER
1
2 P1
KRC-20S (1/2)
2SB1277 2SA1037K KRA102S
2SB1443 KRC104S
I J
L4
52mH
+B
J1
FM+B
SW
Q201
FRONT-END
A1
AM+B
SW
R203
1
22K
RF GND
2
FM ANT
Q203
3
C200 AM ANT
AM+B 0.01
4
OSC GND
SW
8.2V 5
Q202 +B FM+B
8.2V 6
22K +B AM+B
7
OSC GND
8
22K
OSC GND
9
OSC GND
10
OSC GND
11
VT
8.2V 12
+B +B PLL+B
13
IFC OUT
14
8 SDA
15
9 SCL
D200
16
DIG GND
L8 4.7uH 5.1V
17
VDD 5V
+B
C206 47u10
18
IF2 GND
+
8.2V 19
+B +B IF2+B
20
AUDIO OUT
21
10 SD
22
63 S-METER
8.2V 23
+B IF1+B
24
IF1 GND
ME1 (D40-1136-05)
S3
CN1
FWD
R251
10K
FWD/REV Ref.99
1
GND
2
REV
HEAD R
3
Rch
+
HEAD COM
HD1
4
HEAD L
Lch
5
S2
S1
4 6
1 2 3 5
4 6
1 2 3 5
X16-
J1
2/2
A
LA3161