JBL PowerBass PB12, Service Manual

Page: 42 / 43

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
A
B
C
D
E
F
G
H
I
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1
I
H
G
F
E
D
C
B
A
Part No:
Date:
Drawn:
Rev.
Revision 7.2 (PREAMP)
25-Oct-2001
MS/LL
1
Sheet:
1
of
2
6
5
4
3
2
1
CONN 1
NOT USED
U1
U2 U1
TLO64
U1
R16
NOT USED
C9
1k
C8
0r
C7
0r
R15
NOT USED
R17
56k2
R14
68k1
R35
137k
R13
33k2
R9
2k7
C5
220pF
C3
220pF
C2
200uF
C1
200uF
8
10
9
R27
604r
R34
120k
R24
604r
R28
33k2
C19
330pF
C18
330pF
R10
10k
R11
59k
C6
220p
R In
GND
L In
R6
R5
R4
R3
100k
R8
2k7
C4
220pF
Phase Switch
SW SPDT
5k POT
R12
45k3
U2
LM324
U2
C17
150nF
C16
100nF
R30
10k
R26
4k7
R33
12k1
1
3
2
2
3
1
R18
6k8
R20
6k8
U1
U2
C10
100nF
C12
100nF
C13
100nF
C11
100nF
R21
0r
R19
6k8
R22
6k8
R23
0r
LoPass Defeat Sw.
SW SPDT
13
12
14
13
14
12
3
2
1 7
6
5
6
5
7
8
10
9
1
3
2
1
2
3
1
2
3
4
5
6
7
8
9
11
12
10
R1
4k7
R2
4k7
+15V
-15V
C21
100nF
C20
100nF
C23
100nF
C22
100nF
+15V
GND
GND
SIG
-15V
mute
To/From PWRAMP
R25
33k2
3rd Order Hi-Pass
2nd Order LO-PASS
2nd Order LO-PASS
GAIN STAGE
RCA CONNECTOR
DUAL RCA
1
2
3
REMOTE
NOT USED
R
L
B-POST HiLev I/O
IN
R
L
OUT
C30
NOT USED
2nd Order Hi-Pass
To Pin 11 U1/U2
To Pin 4 U1/U2
+15V
-15V
LO PASS CONTROL 1
20k POT
LO PASS CONTROL 2
20k POT
LO PASS CONTROL 3
NOT USED
LO PASS CONTROL 4
NOT USED
+15V
-15V
D50
1N4148
D51
1N4148
D52
1N4148
D53
1N4148
D54
1N4148
D55
1N4148
LEVEL
From PwrAmp
From PwrAmp
1
2
LED1
1
2
LED 2
NOT USED
NOT USED
J1
NOT USED