Integrated Circuit Diagrams - JBL PowerBass PB12 Service Manual

PB12
Integrated Circuit Diagrams (Revision 1 Only)
+6V 15
16
17
V+
18
O/P
19
20
21
V-
22
+15V 23
SD 24
FR 25
I/P 26
GND 27
-15V 28
NOTE: THE PB10/12 REVISION 1 AMPLIFIER MUST ALWAYS BE TESTED
LM324, TLO64, U1, U2
S53AMI/S64AMI - Power Amp Module SAFETY PART
1 +6V
2
3 V+
4
O/P
5
6
7
V-
8
9 +15V
10 SD
11 FR
12 I/P
13 GND
14 -15V
00228
WITH A WOOFER OR 4 OHM RESISTIVE LOAD.
N-Chan JFET
Q1 2N5457
D
S
G
NOTE: THE FOLLOWING PROCEDURES MUST BE
FOLLOWED WHEN INSTALLING NEW S53AMI/S64AMI AMP
MODULES:
FAILURE TO FOLLOW ONE OR MORE OF THESE STEPS
MAY RESULT IN THE INSTANT DESTRUCTION OF THE
MODULE WHEN POWERED UP.
1. Align white indent marker on Amp Module with indent
marker on main PCB; alternately observe position of label
on top of the Module; incorrectly replacing the Module
180° in the PCB slot will result in its destruction.
2. All AC powered test instruments (meters, oscilloscopes,
etc.) must have a floating ground, i.e., be connected to
an isolation transformer.
3. Align and position the Amp Module before soldering.
4. Attach the Amp Module with the mounting screws before
soldering or powering up.
5. Use only rosin-core or non-acid core solder; thoroughly
de-flux the surfaces after soldering.
If the new S53AMI/S64AMI Amp Module has larger mounting
hole(s) in the case, and the stock screws no longer will fit,
and screws of the proper type cannot be obtained locally
order:
(2) part# 60301S (screws)
(2) part# 60301N (nuts)
MPSA56, Q10, Q11
3 Collector
2
Base
1 Emitter
1
2 3
24
2N4401, Q12
3 Collector
2
Base
1 Emitter
1
2 3