McIntosh MCD301, Service Manual

Page: 10 / 26

MAIN
750771 SCH 3 OF 3
2
13 14
10
k
R
15
9
D13
.1
uF
C
14
4
4.75k
R198
Idle 4.5mA
GND
GND
LEFT
.0
02
2u
F
C
11
3
22uF
C117
22uF
C116
10
k
R
15
8
47uF
C131
47
.5
k
R
16
8
47uF
C129
47
.5
k
R
16
7
47
.5
k
R
16
6
47uF
C127
47
.5
k
R
16
5
47
.5
k
R
16
4
3
J13B
.1uF
C139
2
J13A
.1uF
C138
4
1
3
2
G
S
-
+
J14
LEFT HEADPHONE
OUTPUT DRIVER
4.75k
R201 2
1
3
Q23
.1
uF
C
14
3
4.75k
R200
2
1
3
Q22
4.75k
R199 2
1
3
Q21
.1
uF
C
14
2
2
1
3
Q20
100
R207
100
R206
RIGHT
.0
02
2u
F
C
11
2
47uF
C130
47
.5
k
R
16
9
47uF
C128
47uF
C126
.1uF
C146
4
1
3
2
G
S
-
+
J15
.1
uF
C
14
5
D12
10
R196
J16 4
D10
.0022uF
C115
RIGHT VARIABLE
OUTPUT
FILTER
2.67k
R150
2.67k
R151
1.
33
k
R
15
3
2.67k
R149
1.33k
R154
.0022uF
C114
LEFT VARIABLE
OUTPUT
FILTER
2.67k
R148
22uF
C124
LEFT- BALANCED
VARIABLE
OUTPUT DRIVER
VARIABLE
RIGHT
UNBALANCED
OUTPUT
RIGHT UNBALANCED
VARIABLE
OUTPUT DRIVER
499
R175
10k
R162
10k
R163
499
R174
499
R173
LEFT UNBALANCED
VARIABLE
OUTPUT DRIVER
499
R171
10k
R160
10k
R161
VARIABLE
LEFT
BALANCED
OUTPUT
10
R205
10
R197
10
R204
J16 2
10
R195
10
R202
J16 1
10
R194
D9
1.
33
k
R
15
2
1.33k
R155
RIGHT- BALANCED
VARIABLE
OUTPUT DRIVER
22uF
C125
LEFT+ BALANCED
VARIABLE
OUTPUT DRIVER
499
R172
VARIABLE
RIGHT
BALANCED
OUTPUT
499
R170
J16 3
2
1
3
4
K2
10
R203
2
1
3
4
K1
D11
RIGHT+ BALANCED
VARIABLE
OUTPUT DRIVER
RIGHT HEADPHONE
OUTPUT DRIVER
1
4
6
7
8
2
3
5
-
+
U29
22pF
C140
22.1k
R193
100k
R190
1
4
6
7
8
2
3
5
-
+
U30
22.1k
R191
100k
R192
22pF
C141
3
2
1
Q14
3
2
1
Q15
3
2
1
Q18
3
2
1
Q19
3
2
1
Q17
3
2
1
Q16
100
R178
100
R180
100
R181
100
R179
100
R177
100
R176
47uF
C132
47uF
C135
47uF
C137
47uF
C134
47uF
C133
47uF
C136
1k
R182
1k
R187
1k
R184
1k
R185
1k
R186
1k
R183
2
3
1
-
+
8
4
B+
B-
U27A
6
5
7
-
+
U27B
2
3
1
-
+
8
4
B+
B-
U28A
6
5
7
-
+
U28B
2
3
1
-
+
8
4
B+
B-
U26A
6
5
7
-
+
U26B
2
3
1
-
+
8
4
B+
B-
U24A
6
5
7
-
+
U24B
12VA
-12VA
12VA
-12VA
-11.5VA
11.5VA
-11.5VA
11.5VA
11.5VA
-11.5VA
-11.5VA
11.5VA
HMUTE
OMUTE
LEFT+
LEFT-
RIGHT+
RIGHT-
9
10
11
12
13
14
15
16 1
2
3
4
5
6
7
8
ZCEN
DATAO
DATAI
ANR
AGNDR
AOUT R
VA+
VA-
AOUTL
AGNDL
ANL
M\U\T\E\
SCLK
VD+
C\S\
DGND
U25
10
0k
R
15
6
10
0k
R
15
7
10
uF
C
11
8
.1
uF
C
11
9
SCLK DATAI CS
10uF
C120
10uF
C123
.1uF
C121
.1uF
C122
-11.5VA 11.5VA
18uH
L9
5VA
LEVEL
CONTROL
VARIABLE
LEFT
UNBALANCED
OUTPUT
2.
55
k
R
18
8
2.
55
k
R
18
9
J
J
J
J
8
8
8
8
0V
0V
0V
0V
0V
0V
0V
0V
0V
0V