McIntosh MC275 Service Manual page 7

2 MAIN
751376 SCH 1 of 3
J1:1
J1:4
100V
110V JMP1
120V
J1:7
J1:10
J2:1
J2:4
220V
230V
240V
J2:7
J2:10
J5:2
TEST ONLY [+]
NO CONNECTION
APPLY 12VDC
TO ENERGIZE RELAYS
J5:1
WITH NO AC POWER [-]
!
BLK
J3
3
4
K1
D1
.3V
REFER TO CONNECTION
CHART FOR PROPER
PRIMARYCONNECTIONS
J4
WHT
+12V
GP1
6-32
!
+T°
A
J6
2
1
1
RT1 16
B
J7
1
C
J8
1
12V
D
J9
1
E
J10
1
F
J11
1
G
J12
1
!
+T°
H
J13
1
RT2 16
I
J14
1
J
J15
1
9
MC275
! !
1
R1
D2
t
5
350mA
D3
2 6
PRIMARY
3 7
D4
D5
8
4
T1
+480V
L1
J16
1
!
J17
1
T1
ORN
J18
1 .3V
D6
ORN .3V
J19
1
RED
J20
1
RED/YEL
J21
1
!
C1
RED
J22
1
R2
GRN
T°
J23
1
8A
R3
GRN/BLK
T°
J24
1
FIL C
3A
GRN
J25
1
!
+12V +5V
U1
1 3
VIN VOUT
C13
220µF
C9
C4
HS2
+12.6V
D13
C3
+700V
R8
2.2k
D14
C7 C14
D16
R10
C2
D8 C5 680µF
47µF
R11
U2
R4
MAIN RELAY
DRIVER
0V
.6V
1
Q1 5V
PWR RLY
R9
4.75K
C8
-225V
22µF
D15 D17 R12
267k
R7
430
C11
D7
2 1
AC
C6 680µF
3 4
AC
+12.6V
MP1
R5
1.0 2 W
D9
FIL B
D10
C10 C12
FIL A
D11
R6
1.0 2 W
D12
10
+350V
R21
46.4k
R22
30k
C18
C17 680µF
47µF
R15
681
C15 680µF
D18
-BIAS ADJUST-
ADJUST R19 FOR -60 TO -62VDC
ACROSS J34 AFTER 5 MINUTES ON
AND NO INPUT SIGNAL
R19
100k
2
R13
BIAS
47.5k
R14 C16
100k
FIL C
R17
4.75K
+5V
R18
10K
Q2
2 3 1
Q3
R16 R20