Alto OEX-400, Service Manual

Page: 9 / 37

1 2 3 4 5 6 7 8
A
B
C
D
8 7 6 5 4 3 2 1
D
C
B
A
3
2
1
U23A
4580M
R41
22K
C115
22P
R176
6K8
R42
22K
3
2
1
U16A
4580M
R173
5K6
C116
22P
C55
47u/25V
R184
680R
R172
5K6
3
2
1
U15A
4580M
R177
39K
C197
10P
MN-EQ-SOURCE
5
6
7 U15B
4580M
R178
39K
C198
10P
R175
6K8
MN-EQ-OOL-2
MN-EQ-OOL-1
R120
8K2
R189
2K7
5
6
7
U16B
4580M
R43
22K
C117
22P
C56
47u/25V R44
22K
HP-OUT-L
HP-OUT-R
MO-OUT-L
MO-OUT-R
TAPE-OUT
R207
27K
3
2
1
U17A
4580M
C58
47u/25V
R213
8K2
R137
36K
C81
22P
C59
47u/25V
R45
22K
3
2
1
U19A
BA15218N
5
6
7
U19B
BA15218N
C119
22P
R216
10K0
R159
120R
R160
120R
R158
120R
R157
120R
5
6
7
U17B
4580M
C61
47u/25V
R46
22K
3
2
1
U18A
BA15218N
5
6
7
U18B
BA15218N
R217
10K0
C118
22P
1
3
2
VR22
W50K
R214
100R 1/4W
R215
100R 1/4W
MONITOR OUT
MASTER(VOLUMES)
C57
47u/25V
R200
100K
D20
4148
3
2
1
U20A
4580M
R199
100K
D16
RED
D14
YE
D11
GR
D10
GR
+10DB 0DB -10DB -30DB
MN VMETER
8
4
U14C
4580M
8
4
U15C
4580M
8
4
U16C
4580M
8
4
U17C
4580M
C166
0.1u
C167
0.1u C169
0.1u
C168
0.1u C170
0.1u C172
0.1u
C171
0.1u C173
0.1u
8
4
U18C
4580M
C174
0.1u
C175
0.1u
R150
10
R151
10
+VCC
-VCC
8
4
U20C
4580M
C152
0.1u
C153
0.1u
+VCC6
-VCC6
R148
10
R149
10
+VCC
-VCC
8
4
U19C
4580M
C164
0.1u
C165
0.1u
1
3
2
VR21
W50K
MAIN-IN-EQ
1
2
3
4
J13
CON4
TO AMP IN
5 4
2
3 12
U21A
LM339
7 6
1
U21B
LM339
9 8
14
U21C
LM339
11 10
13
U21D
LM339
5 4
2
3 12
U22A
LM339
7 6
1
U22B
LM339
9 8
14
U22C
LM339
11 10
13
U22D
LM339
R84
10K
E
2
C
3
B
1
Q1
PNP
E
2
C
3
B
1
Q2
PNP
R156
120R
D1
1N4148
R155
120R
R192
470R
D2
1N4148
R191
470R
R82
10K
D17
RED D15
YE D13
GR D12
GR
R194
43R
R195
510R
R196
1.2K
R197
2.7K
R198
22K
D19
4148
C60
47u/25V
R201
100K
D21
4148
5
6
7
U20B
4580M
R202
100K
R83
10K
D22
4148
+VCC6
-VCC6
+VCC6
-VCC6
MO VMETER
+10DB 0DB -10DB -30DB
+VCC6
-VCC6 +VCC6
-VCC6
R247
10K
C190
47UF/25V
C191
47UF/25V
C188
47UF/25V
C189
47UF/25V
R248
1K
R249
10K NC
+VCC1
-VCC1
+VCC8
-VCC8
R253
4.7K
R254
4.7K
R262
15.0K
5
6
7
U10B
4580M
R264
27.0K
C238
100nF
R265
12.0K
C237
0.22u/50V
CI00185
C239
47u/25V
R255
27K
R255 IS NOT USED
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