McIntosh MC275 Service Manual page 9

2 MAIN
751376 SCH 3 of 3
V9 PLT
J32:6
3
V8 CATH
J32:10
3
V8:1
KT88
V8 GRID
J32:9
5
3
R64
FIL C C43
J32:13
3
FIL C
1µF
FIL A
J32:14
3
FIL A R60 FIL A
+12.6V
J32:11
3
+12.6V -225V FIL A
J32:1
GND
J32:2
3
R61
J32:3
C44
1µF
R65
V9 GRID
J32:5
5
3
V9:1
L OUT 16 KT88
J32:7
3 L OUT 16
V9 PLT
J32:8
3
V10 PLT
J33:6
3
V11 CATH
J33:10
3
KT88
V11:1
V11 GRID
J33:9
5
3
R66
C45
FIL C
J33:13
3
FIL C
1µF
FIL B
J33:14
3 R62
FIL B
FIL B
BIAS
J33:1
3
BIAS -225V
J33:2
FIL B
+700V
J33:11
3 R63
+700V
J33:12
C46
+350V
J33:3
3
+350V
J33:4
1µF
R67
V10 GRID
J33:5
5
3
KT88
V10:1
R OUT 16
J33:7
3
R OUT 16
V11 PLT
J33:8
3
R68
4
220 5W
C47
2200pF
KT88
2 7
FIL C
V8:2
L4
L1
KT88
2 7
FIL C
R72
V9:2
R69
4
220 5W
AUDIO DETECTOR
1
Q16
D21
R70
4
220 5W
KT88
2 7
R73
FIL C
V11:2
L3
L2
KT88
C48
2200pF
2 7
FIL C
V10:2
R71
4
220 5W
13
MC275
L OUT 16
R75
475k
L SENTRY
MONITOR
DETECTOR
D23
1
Q18
C54
+5V
R77
100K
R74
+5V
100K
U31
1
Vcc
4
AUDIO
2
GND
2
C53
1
Q17
.47µF
D22
Main - Output
R OUT 16
R76
475k
D24
R SENTRY
1
MONITOR Q19
DETECTOR
C55
4 TERMINAL
L AUDIO TRANSFORMER
BLU
J35
1
WHT
J36
1
T2
YEL YEL
J37
1 1
ORN
1
R80
BLK
22.1k
J38
1
RED
1
R78
WHT/YEL BRN
J39
1 1
RED
J40
+480V 1
BRN
WHT/BLU
J41
1
J34:2
GRID
-BIAS ADJUST-
BIAS TP ADJUST R19 FOR -60 TO -62VDC
J34:1
ACROSS J34 AFTER 5 MINUTES ON
GND
AND NO INPUT SIGNAL
BLU
J42
1
WHT
J43
1
T3
YEL YEL
J44
1 1
ORN
1
R81
22.1k BLK
J45
1
RED
R79 1
WHT/YEL BRN
J46
1 1
RED
J47
+480V 1
BRN
WHT/BLU
J48
1
R AUDIO TRANSFORMER
14
751379 SCH
J1
L 16(+)
BP1
J2
L 8(+)
BP2
R1
J3 L 4(+)
BP3
C1
J4
L(-)
BP4
4
TERMINAL
J5
R 16(+)
BP5
J6
R 8(+)
BP6
R2
J7
R 4(+)
BP7
C2
J8
R(-)
BP8