Kenwood KAC-959 Service Manual page 7

A B
PREAMPLIFIER UNIT
(X08-4080-10) (A/2)
D101 D105
1
0V
R105 10K
12
13
D103 D107
C101
10u35
+
C102
10u35
+
0V
D104 D108
2
2
R106 10K
3
D102 D106
0V
16.8V
J1
-16.6V
Lch
D201 D205
Ach 0V
R205 10K 12
Rch
13
D203 D207
3
R201 C201
1K 10u35
Lch
+
Bch
R202 C202
1K 10u35
Rch
+
D204 D208
2
R206 10K 3
Lch
D202 D206
0V
4
SUBch
16.8V
Rch
-16.6V
5
D301 D303
0V
C301
10u35 R304 1K 12
+ 13
D302 D304
0V
6
SIGNAL LINE IC1-3,5 : UPC4574C
IC4 : NJM2058D
GND LINE
B LINE
B LINE
2SA733(A) 2SC945(A) 2SA1110
2SA817A 2SC2590
2SA992
2SC1627A
7
2SC1845
C D
ISOLATION
AMPLIFIER
IC1
IC1
R121 0V
(1/4)
R111
7 (3/4)
C115
14 6.8K 82K 10
8 10u35
9
+
R109
0V
0V 8.2K
R115 6.8K
0V
R113 6.8K C113 22P
R123
C1 1000P 8
82K
R1 1K
R124
5
R114 6.8K 82K C114 22P
R116 6.8K
R110
0V
8.2K
C116
6
4
7 10u35
R112
1 5
+
6.8K R122 0V 11
0V
6
IC1
0V IC1
82K
(2/4)
(4/4)
ST
S4
ISOLATION
AMPLIFIER INPUT
IC2 SELECTOR
IC2
R221 0V (3/4)
(1/4)
R211 3
C215
6.8K 82K
14 10 11
10u35
8
9
+
R209
4
0V
0V S4
8.2K
0V
R215
0V
AB A
6.8K
R213 6.8K C213
R223 22P
C2 1000P
4
82K
R2 1K
R224
1
R214 6.8K 82K C214 22P
R216 6.8K
0V
R210
0V
8.2K
C216
6
7 10u35
1 R212 5
+
6.8K R222 IC2
0V
2
IC2 0V
(4/4)
82K
(2/4)
C309 22P
R312 10K
0V 9
10
IC5
(3/4)
R352 R351 R350 R349
2.2K 2.2K 2.2K 2.2K SIGNAL
MIXER
S5
INPUT
ISOLATION
SELECTOR
AMPLIFIER
IC3 R317
IC3
0V
(1/4) 1.5K
R307
(2/4)
C308
14 6.8K 3
10u35
1
2
+
R306
0V
S5
8.2K
R309 6.8K
0V
R308 6.8K C307 22P
SUB - AB
C3 1000P
R3 1K
Q101,102,201,202,307 D1-4 : RD8.2JS(B)
: 2SC945(A) (Q,P) D101-110,201-210,301-305
Q103-106,203-206,301,302 : 1SS133
: 2SA733(A) (Q,P)
Q107-110,207-210,303,304
: 2SC1845(F,E)
DTA124ESA 2SC4137 NJM2058D
E F
IC4
0V
C117 C119
(1/4)
0.22 0.22
12
14
13
R129
5.6K 0V
S1
HPF
S1
A.CH HPF
OFF 150Hz 80Hz
PHASE
INVERTER
0V
IC5
R130
(1/4)
12
5.6K R136
9 14
8 10K 13
C118 C120 10
IC4
0.22 0.22
0V
R138 10K
(2/4) 0V
C122 22P
S3
MONO OPERATION
S3
0V IC4
C217 C219
(3/4)
0.22 0.22 3
1
2
R229
5.6K
0V
HPF
S2
S2
B.CH HPF
OFF 150Hz 80Hz
PHASE
INVERTER
0V
IC5
R230 (2/4)
3
5.6K R236
6 1
4
7 10K
2
C218 C220
5
11
0.22 0.22 IC4
0V R238 10K
0V (4/4)
C222 22P
C310 22P
0V R314 10K 0V
R313
C311 R315
10K
8 6 4
7 10u35 100K
5
+
IC5
11
(4/4)
PHASE
INVERTER
0V
SUB. CH LPF FREQ.
C315 C316
IC3
1u50 1u50
10
50Hz 200Hz
VR4 (3/4)
R318 + +
C319
11
3.3K R319 5
7 10u35
R320
6
10K(C) 10K(C) 3.3K
+ 5.1K
4
0V
0V
C313
0.47
SUB. CH
INPUT
LPF
LEVEL
CAUTION: For continued safety, replace safety critical components only with
manufacturer's recommended parts (refer to parts list).
components. For continued protection against risk of fire, replace only with same type
and rating fuse(s). To reduce the risk of electric shock, leakage-current or resistance
UPC4574C UPC494C measurements shall be carried out (exposed parts are acceptably insulated from the
supply circuit) before the appliance is returned to the customer.
G H
C135 10P
0V
Q103 Q105
R141 C125
6.8K 10u35 R157 18K
C123 + 0.6V
0V -1.2V
22u35
C133 47P
+
R153 C129
Q101
100 1000P
Q107 Q109
-23.4V
MUTE
Q108 Q110
R154 C130
100 1000P
Q102
C134 47P
-23.4V
0V
0V -1.2V
R142 C126
0.6V
6.8K 10u35 R158 18K
C124
22u35 +
C136 10P
Q104 Q106
+
0V
14.3V
C235 10P
0V
R241 C225 Q203 Q205
6.8K 10u35 R257 18K
+
C223 0.6V
22u35
C233 47P
+
R253 C229
Q201
100 1000P
Q207 Q209
-23.4V
MUTE
R254 C230 Q208 Q210
100 1000P
Q202
C234 47P
-23.4V
0V 0V
-1.2V
R242 C226
0.6V
6.8K 10u35 R258 18K
C224
22u35
+
0V C236 10P
+ Q204 Q206
R8
12K -5.1V,5.7V(MUTE)
14.3V
C6
1u50
+
16.8V R4 82 2W
R6 82 2W
-16.6V
Q301-304
2-STAGE
DIFFERENTIAL
AMPLIFIER
0.6V
IC3
C324 10P
0V 0V
(4/4)
Q301 Q302
C317 R325 C335
1u50 2.2K 10u35 R333 18K
8
9
+ +
-1.2V
C323 47P 0V
0V
R324 4.7K
R329 C321
100 100P
C318 4700P
-44.0V
Q303 Q304
INFRASONIC
FILTER
Q307
MUTE
indicates safety critical
I J
14.3V
Q103-110
2-STAGE
R159 100
5
DIFFERENTIAL
AMPLIFIER
6
E3
X09-A/2
-CN2
1 1 BRN
-23.4V
2 2 BRA
2/2
3 3 BLN
4 4 BLA
A
5 5 ALN
-24.0V
6 6 ALA
7 7 ARN
8 8 ARA
-24.3V
-24.0V
-23.4V
8
R160 100
7
R259 100
Q203-210
3
2-STAGE
4
DIFFERENTIAL
AMPLIFIER
E4
-23.4V
1 1 NF
X09-A/2
-CN3
2 2 A CLAS
-24.3V
3 -LB
2/2
-24.0V
B
4 GND
25.2V
5 +LB
-24.3V
-45.4V
6 -HB
14.3V
-24.0V 7 +15V
8 MUTE
-23.4V
2
R260 100
1
R5 82 2W
R7 82 2W
E2
X09-A/2
-CN1
1 1 BR-
2 2 BR+
2/2
3 3 BL+
4 4 BL-
C
5 5 AR-
6 6 AR+
7 7 AL+
R334 100
8 8 AL-
C325
220P
-44.0V
-44.5V
C25
220u50
+
-45.2V
KAC-959(JEKM) (1/2)
KAC-959