McIntosh MC275 Service Manual page 13

BAL INPUT
5
751377 SCH
12AT7
McIntosh
USA
MP6 MP8
V1
MP7 MP9
+5V
4 5 6
R G B
DS1:1 DS1:2 DS1:3
3 2 1
R77
475
R78 R79
3.32K 681
D12 D13 D14 D15
J7:11
+5V
J7:12 J7:13
2
J7:14 J7:15
L RED
J7:18 L RED
2
R RED
J7:17
R RED
2
ORN 1
J7:1
ORN 1
2
ORN 2
J7:2
ORN 2
2
ORN 3
J7:3
ORN 3
2
ORN 4
J7:4
ORN 4
2
ORN 5
J7:5
ORN 5
2
ORN 6
J7:6 ORN 6
2
ORN 7
J7:7
ORN 7
2
GRN
J7:8
GRN
2
J7:9
MP1 MP2 MP3 MP4 MP5
UNBAL INPUT
6
LEFT INPUT
12AT7 12AX7 12AX7
McIntosh McIntosh McIntosh
USA USA USA
MP10 MP12
V2 V3 V4
MP11 MP13
4 5 6 4 5 6 4 5
R G B R G B R G
DS2:1 DS2:2 DS2:3 DS3:1 DS3:2 DS3:3 DS4:1 DS4:2
3 2 1 3 2 1 3 2
R86
R80 R83
475 475 475
R81 R82 R84 R85 R87
3.32K 681 3.32K 681 3.32K
D16 D17 D18 D19 D20 D21 D22 D23 D24 D25
8
Tube Lighting
21
MC275
PWR CNTRL
7
751377 SCH
RIGHT
12AX7 12AT7
McIntosh McIntosh
USA USA
MP14 MP16 MP18
V5 V6
MP15 MP17 MP19
6 4 5 6 4 5 6
B R G B R G B R
DS4:3 DS5:1 DS5:2 DS5:3 DS6:1 DS6:2 DS6:3 DS7:1
1 3 2 1 3 2 1
R89 R92
475 475
R88 R93 R94
R90 R91
681 3.32K 681 3.32K 681
D26 D27 D28 D29 D30 D31 D32 D33 D34 D35
TUBE LT
8
751377 SCH
PC IN
J8:1
2
3
1
7
Power Control
4
6
5
J8:2
PC OUT
BREAKAWAY
12AT7
McIntosh L
6
USA
1
V7
J9:1
J9:2
2
R/MONO
4 5 6
G B
DS7:2 DS7:3
3 2 1
R95
475
BREAKAWAY
R96 R97
3.32K 681
D36 D37 D38
5
C36
.47µF
C37
Balanced
.47µF
Input
R98 R99 R100
100K 150K 100K
L
C38
4.7µF
2
+
3
-
1
G
S J10
R101
1M
R/MONO
C39
4.7µF
2
+
3
-
1
G
S
J11
R102
1M
22
751377 SCH
PC IN
J13:12
2
PC GND
J13:4
2
J13:5
TUBE LT
J13:10
2
GND
J13:7
2
J13:8
PC OUT
J13:1
2
J13:2
Unbalanced Input
L UNBAL
J14:6
3
J14:7 R UNBAL
3
J14:5 GND
3
R103
150K
L BAL+
J14:2
3
C40
4.7µF
L BAL-
J14:1
3
R104 R106 R108
1M 150K 33.2K
R BAL+
J14:4
3
C41
4.7µF
R BAL-
J14:3
3
R105 R107 R109
1M 150K 33.2K