Alto L-12 Service Manual page 12

1 2
D
C2
VR2
47u/25V
B50K
INS2-CH1
INS2-CH1
C1
682(M)
R1
VR3A
5
3K
500KC
6
R21
C10
6K2
152(M)
VR3B
500KC
C
LD1
YEL
(SOLO)
1
2
3
SW4A D1
PS-42E85L BAS316
(LOGIC=2.0V or 0.5V)
3
L-CUT1-ON
LO-CUT-CH1
1
L-CUT1-OF
SW PS-22E85L-2
SW2A
VR11
B TRIM-CH1
O10K
+VCC
A
1 2
3
EQ HI (12K)
MID (FREQ=100Hz-8K) C8
C7
VR1
6.8n(M) 6.8n(M)
B50K
C5 22P
R18
R2 R3
3K9
10K 10K
2
1
3
R6
U1A
R4
5K1
4580M
10K
7
U1B
4580M C12
C11
33n(M)
33n(M)
R22 VR4
R24 R25
6K2 B50K
5K6 5K6
LO (80Hz)
-VCC
DIR-OUT1
R23
2K2
LOGIC
LOGIC
+RVCC
2
INS1-CH1
R47
10K
R46
R41
10K
PGND
100K
TRIM2-CH1
D2
+RVCC
4148
U3A
2 PGND R45
1
4580M 10K
TRIM1-CH1 R44
3
82R
D3
4148
R42
R43
100K
C21
8K2
1uF
PGND PGND PGND
C17 C19
100n 100n
U2C U1C
4580M 4580M
-VCC
C18 C20
100n 100n
3
4 5
R7
C9
5K1 22P
C6
PS-22E85L-2
22P
SW1B
4
R19
5
VR5A
1M
6 6
10KD
C3
5
47u/25V
2
U2B
1 R40
C28
3
15K 4580M
47u/25V
LEVEL
U2A
4580M
+VCC
R26
PS-22E85L-2
3K3 SW1A
1
2
3
LD2 MUTE
RED
R5
10K
5
U4B
5
TR1
R50 D4
7
HR
4148
6
27K
393
C22
1uF
R48
PGND
U4A 10K
8
LD3
3
R49 TR2
LED-2P
1
7002
2
4K7
紅 綠
4
R51
C23
393
1K
470P
PGND
4 5
11
6 7
L12MN2-CH1(2/5)
PAN
R29
SW7A
4K7 R8
PS-22E85L
1
5K1
R20 2
VR6
12K 3
LEFT-BUS
W50K
SW7B
7
R9
PS-22E85L
4
5K1
5
C4
6
47u/25V
R30 RIGHT-BUS
SW6A
4K7
R10
PS-22E85L
1
5K1
2
3
SW6B
R11
PS-22E85L
4
5K1
5
6
SW5A
R12
PS-22E85L
1
5K1
2
3
SW5B
R13
PS-22E85L
4
5K1
5
6
SW4C
R27
PS-42E85L
7
6K8
8
9
SW4D
R28
SW4B
PS-42E85L
10
6K8
PS-42E85L
11
4 12
6
SOLO(PFL)
SW3A
AUX-POST
PS-22E85L
1
VR7
2
W50K
R14
3
SW3B 6K8
PS-22E85L
4
AUX-POST
5
6
VR8
W50K
R15
6K8
AUX1/2 PRE/POST
R16
AUX-PRE
6K8
VR9
W50K
R17
AUX-PRE
6K8
VR10
W50K
Titel
PCB# L12MN2.PCB
Size Model No:
ALTO L12
A3
12-Jul-2003
Date:
File: CH1.Sch
6 7
8
D
SUB1
SUB2
SUB3
C
SUB4
AFL-L
AFL-R
AUX3
AUX4
B
AUX1
AUX2
A
Revision
VER030712
Sheet 2 of 5
Drawn By: BOW
8