Nad C 725 BEE Service Manual

Page 2

TABLE OF CONTENTS

DESCRIPTION P A G E
SERVICE CAUTION .................................................................... 3-4
REAR PANEL/FRONT PANEL VIEW ............................................... 5
SPECIFICATIONS .................................................................. 6-7
WIRING DIAGRAM ........................................................................ 8
BLOCK DIAGRAM .................................................................... 9-18
ALIGNMENT PROCEDURE ........................................................ 19
SCHEMATICS ......................................................................... 20-23
PCB LAYOUT ......................................................................... 24-28

TROUBLE SHOOTING GUIDE29

ELECTRICAL PARTS LIST .................................................... 30-46
EXPLODED VIEW ....................................................................... 47
EXPLODED VIEW PARTS LIST ....................................................... 48
C7ZSBEE PACKING ACCESSORY AND PARTS LIST ............................. 49

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TROUBLESHOOTING GUIDE

PUSH THE POWER SWITCH TO ON
NO NO NO CHECKTHE SVSUPPLY
IS THE SCOLOURVLED AMBER LICHT7 IS IT RED7 IS IT BLUE (POWER BOARD)

VES VES

CHECK THE LED CONTROL CIRCUIT
AND PROTECTION CIRCUIT
CAN FRESSING AW KEY To MAKE ARE ALL POWER SUPPLIES OK? No CHECK ALL POWER SUPPLIES
THE UNIT WORK NORMALLY7

CHECK KEV CIRCUIT

IS THERE PROTECT! FLASH ON VFD. CHECK THE PROTECTION CIRCUIT

NO

CHECK THE MAIN TRANSFORMER
AND POWER BOARD

IS THE SPK om NORMAL? ILpl IS THE own no LEVEL NORMAU IL.I Is THE DC SERVO CIRCUIT om 0 CHECK mg no save cm I
VES VES VES
CHECK THE AMP CIRCUIT SECTION
NO NO
IS THERE SIGNAL OUTPUT7 IS THE POWERAMP INPUT NORMAN CHECK THE PREAMP CIRCUIT SECTION
VES IVES
NO
IS THE MUTE SIGNAL HIGH LEVEL? CHECK THE MUTE CIRCUIT
IVES
IS THE VOLUME CONTROL CIRCUIT NO
I NORMAL? I-II CHECK THE VOLUME CONTROL CIRCUIT
IVES
NO
I '5 THE TONENgEfigcRCUT I-II CHECK THE TONE DEFEAT CIRCUIT I
IVES
NO
IS THE PREAMP MODULE NORMAL7 CHECK THE PREAMP MODULE

CHECK THE AMP CIRCUIT SECTION

i<
m
m

VES VES
5 THE THD BAD7 IS THE SIN BAD7 TURN THE TRANSFORMER

NO

CHECK THE AMP CIRCUIT SECTION

I

ADJUST THE IDLE CURRENT OR
'3 THE DLE CURRENT NOR 7 CHECK THE IDLE CURRENT CIRCUIT

VES
CHECK OTHER PATRS OF THE
AMP SECTION
IS THE SPK OUT NORMAL WHEN NC IS THE CABLE FROM TUNER MODULE N0
INPUT IS TUNER . TO KEVBOARD 0K7 CHECK THE CABLE
VES VES
=I CHECK THE TUNER MODULE
No NO
IS THE REMOTE CONTROL 0K7 IS THE IR INIOUT NORMAL7 CHECK THE R INIOUT CIRCUIT
VES

IS THE REMOTE HANDSET ITSELF
NORMAL7

CHECK THE HANDSET ITSELF

=I CHECK THE KEV BOARD AND MCU
5 THE 12V SUPP NORMAL? N0 CHECK THE .12v SUPPLV CIRCUIT
' IPOWER BOARD)

VES

VES

OK

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