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MICROFILM
XM-7527
US Model
Canadian Model
AEP Model
UK Model
E Model
SPECIFICATIONS
SERVICE MANUAL
STEREO POWER AMPLIFIER


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TABLE OF CONTENTS
1. SERVICE MODE ............................................................. 3
2. GENERAL .......................................................................... 4
3. DISASSEMBLY
3-1. Side Plate and Bottom Plate .................................................. 7
3-2. Amplifier/Power Board and LED Board .............................. 7
4. ELECTRICAL ADJUSTMENT .................................... 8
5. DIAGRAMS
5-1. Block Diagram ­ Amplifier Section ­ .................................. 9
5-2. Block Diagram ­ Power Section ­ ...................................... 10
5-3. IC Block Diagram ............................................................... 11
5-4. Printed Wiring Board ­ Filter/Amplifier Section ­ ............. 12
5-5. Schematic Diagram ­ Filter/Amplifier Section ­ ............... 13
5-6. Printed Wiring Board ­ Power Section ­ ............................ 14
5-7. Schematic Diagram/Printed Wiring Board
­ LED/Power Section ­ ...................................................... 15
6. EXPLODED VIEWS
6-1. Plate and Cover Section ...................................................... 16
6-2. Board and Heat Sink Section .............................................. 16
7. ELECTRICAL PARTS LIST ........................................ 17
Notes on chip component replacement
· Never reuse a disconnected chip component.
· Notice that the minus side of a tantalum capacitor may be
damaged by heat.


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SECTION 1
SERVICE NOTE
Clearing the Protector During Repairs
· OVER CURRENT : Detects overcurrent during output.
· OFF SET : Detects DC offset at the speaker terminal.
1. Clearing the OVER CURRENT protector
1 When the position of the MODE switch (S801/power board)
is set to HI-VOLTAGE :
Cut the jumper wire JW065 of the amplifier board.
2 When the position of the MODE switch (S801/power board)
is set to HI-CURRENT :
Cut the jumper wire JW066 of the amplifier board.
2. Clearing the OFF SET protector
· Cut the jumper wire JW024 of the amplifier board.
3.
TEST TONE Function
1 Press the TEST TONE button (S805/amplifier board) with the
power ON. The amplifier is normal if sound is produced from
the speaker.
2 If no sound
: Problem causer by incorrect connecttion of the power supply
system or sperker system.
: The signals input by the RCA cable before the amplifier system
are abnormal.
Adjustment Location:
VR201
VR101
JW066
JW065
JW024
S805
TEST TONE
- POWER BOARD - (Component side)
- AMPLIFIER BOARD - (Component side)
S801
MODE


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SECTION 2
GENERAL
This section is extracted from
instruction manual.


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