NAD C 725BEE User manual

NAD
SERVICE MANUAL
C 725BEE
STEREO
RECEIVER
C 725BEE STEREO RECEIVER


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 GUIDE…………………......................................29
ELECTRICAL PARTS LIST…………………………………………….30-46
EXPLODED VIEW……………………………………………………………..47
EXPLODED VIEW PARTS LIST……………………………………………....48
C725BEE PACKING ACCESSORY AND PARTS LIST.............................49


PRODUCT SAFETY SERVICING GUIDELINES
CAUTION : DO NOT ATTEMPT TO MODIFY THIS PRODUCT IN
ANY WAY. NEVER PERFORM CUSTOMIZED INSTALLATIONS
WITHOUT MANUFACTURER’S APPROVAL. UNAUTHORIZED
MODIFICATIONS WILL NOT ONLY VOID THE WARRANTY, BUT
MAY LEAD TO YOUR BEING LIABLE FOR ANY RESULTING
PROPERTY DAMAGE OR USER INJURY.
SERVICE WORK SHOULD BE PERFORMED ONLY AFTER YOU
ARE THOROUGHLY FAMILIAR WITH ALL OF THE FOLLOWING
SAFETY CHECKS AND SERVICING GUIDELINES. TO DO
OTHERWISE, INCREASES THE RISK OF POTENTIAL HAZARDS
AND INJURY TO THE USER.
WHILE SERVICING, USE AN ISOLATION TRANSFORMER FOR
PROTECTION FROM AC LINE SHOCK.
SAFETY CHECKS
AFTER THE ORIGINAL SERVICE PROBLEM HAS BEEN
CORRECTED. A CHECK SHOULD BE MADE OF THE
FOLLOWING.
SUBJECT : FIRE & SHOCK HAZARD
1. BE SURE THAT ALL COMPONENTS ARE POSITIONED IN
SUCH A WAY AS TO AVOID POSSIBILITY OF ADJACENT
COMPONENT SHORTS. THIS IS ESPECIALLY IMPORTANT
ON THOSE MODULES WHICH ARE TRANSPORTED TO AND
FROM THE REPAIR SHOP.
2. NEVER RELEASE A REPAIR UNLESS ALL PROTECTIVE
DEVICES SUCH AS INSULATORS, BARRIERS, COVERS,
SHIELDS, STRAIN RELIEFS, POWER SUPPLY CORDS, AND
OTHER HARDWARE HAVE BEEN REINSTALLED PER
ORIGINAL DESIGN. BE SURE THAT THE SAFETY PURPOSE
OF THE POLARIZED LINE PLUG HAS NOT BEEN DEFEATED.
3. SOLDERING MUST BE INSPECTED TO DISCOVER POSSIBLE
COLD SOLDER JOINTS, SOLDER SPLASHES OR SHARP
SOLDER POINTS. BE CERTAIN TO REMOVE ALL LOOSE
FOREIGN PARTICLES.
4. CHECK FOR PHYSICAL EVIDENCE OF DAMAGE OR
DETERIORATION TO PARTS AND COMPONENTS. FOR
FRAYED LEADS, DAMAGED INSULATION (INCLUDING AC
CORD). AND REPLACE IF NECESSARY FOLLOW ORIGINAL
LAYOUT, LEAD LENGTH AND DRESS.
5. NO LEAD OR COMPONENT SHOULD TOUCH A RECEIVING
TUBE OR A RESISTOR RATED AT 1 WATT OR MORE. LEAD
TENSION AROUND PROTRUDING METAL SURFACES MUST
BE AVOIDED.
6. ALL CRITICAL COMPONENTS SUCH AS FUSES,
FLAMEPROOF RESISTORS, CAPACITORS, ETC. MUST BE
REPLACED WITH EXACT FACTORY TYPES, DO NOT USE
REPLACEMENT COMPONENTS OTHER THAN THOSE
SPECIFIED OR MAKE UNRECOMMENDED CIRCUIT
MODIFICATIONS.
7. AFTER RE-ASSEMBLY OF THE SET ALWAYS PERFORM AN
AC LEAKAGE TEST ON ALL EXPOSED METALLIC PARTS OF
THE CABINET, (THE CHANNEL SELECTOR KNOB, ANTENNA
TERMINALS. HANDLE AND SCREWS) TO BE SURE THE SET
IS SAFET TO OPERATE WITHOUT DANGER OF ELECTRICAL
SHOCK. DO NOT USE A LINE ISOLATION TRANSFORMER
DURING THIS TEST USE AN AC VOLTMETER, HAVING 5000
OHMS PER VOLT OR MORE SENSITIVITY, IN THE
FOLLOWING MANNER; CONNECT A 1500 OHM 10 WATT
RESISTOR, PARALLELED BY A .15 MFD, 150V AC TYPE
CAPACITOR BETWEEN A KNOWN GOOD EARTH GROUND
(WATER PIPE, CONDUIT, ETC.) AND THE EXPOSED
METALLIC PARTS, ONE AT A TIME.
MEASURE THE AC VOLTAGE ACROSS THE COMBINATION
OF 1500 OHM RESISTOR AND .15 MFD CAPACITOR.
REVERSE THE AC PLUG AND REPEAT AC VOLTAGE
MEASUREMENTS FOR EACH EXPOSED METALLIC PART.
VOLTAGE MEASURE MUST NOT EXCEED 75 VOLTS R.M.S.
THIS CORRESPONDS TO 0.5 MILLIAMP AC ANY VALUE
EXCEEDING THIS LIMIT CONSTITUTES A POTENTIAL
SHOCK HAZARD AND MUST BE CORRECTED IMMEDIATELY.
SUBJECT : GRAPHIC SYMBOLS
SUBJECT : TIPS ON PROPER INSTALLATION
1. NEVER INSTALL ANY PRODUCT IN A CLOSED-IN RECESS,
CUBBYHOLE OR CLOSELY FITTING SHELF SPACE. OVER
OR CLOSE TO HEAT DUCT, OR IN THE PATH OF HEATED
AIR FLOW.
2. AVOID CONDITIONS OF HIGH HUMIDITY SUCH AS:
OUTDOOR PATIO INSTALLATIONS WHERE DEW IS A
FACTOR, NEAR STEAM RADIATORS WHERE STEAM
LEAKAGE IS A FACTOR, ETC.
3. AVOID PLACEMENT WHERE DRAPERIES MAY OBSTRUCT
REAR VENTING. THE CUSTOMER SHOULD ALSO AVOID THE
USE OF DECORATIVE SCARVES OR OTHER COVERINGS
WHICH MIGHT OBSTRUCT VENTILATION.
4. WALL AND SHELF MOUNTED INSTALLATIONS USING A
COMMERCAL MOUNTING KIT MUST FOLLOW THE FACTORY
APPROVED MOUNTING INSTRUCTIONS A PRODUCT
MOUNTED TO A SHELF OR PLATFORM MUST RETAIN ITS
ORIGINAL FEET (OR THE EQUIVALENT THICKNESS IN
SPACERS) TO PROVIDE ADEQUATE AIR FLOW ACROSS
THE BOTTOM, BOLTS OR SCREWS USED FOR FASTENERS
MUST NOT TOUCH ANY PARTS OR WIRING. PERFORM
LEAKAGE TEST ON CUSTOMIZED INSTALLATIONS.
5. CAUTION CUSTOMERS AGAINST THE MOUNTING OF A
PRODUCT ON SLOPING SHELF OR A TILTED POSITION,
UNLESS THE PRODUCT IS PROPERLY SECURED.
6. A PRODUCT ON A ROLL-ABOUT CART SHOULD BE STABLE
ON ITS MOUNTING TO THE CART. CAUTION THE
CUSTOMER ON THE HAZARDS OF TRYING TO ROLL A CART
WITH SMALL CASTERS ACROSS THRESHOLDS OR DEEP
PILE CARPETS.
7. CAUTION CUSTOMERS AGAINST THE USE OF A CART OR
STAND WHICH HAS NOT BEEN LISTED BY UNDERWRITERS
LABORATORIES, INC. FOR USE WITH THEIR SPECIFIC
MODEL OF TELEVISION RECEIVER OR GENERICALLY
APPROVED FOR USE WITH T.V.’S OF THE SAME OR
LARGER SCREEN SIZE.
8. CAUTION CUSTOMERS AGAINST THE USE OF EXTENSION
CORDS, EXPLAIN THAT A FOREST OF EXTENSIONS
SPROUTING FROM A SINGLE OUTLET CAN LEAD TO
DISASTROUS CONSEQUENCES TO HOME AND FAMILY.
THE LIGHTNING FLASH WITH ARROWHEAD SYMBOL, WITHIN AN
EQUILATERAL TRIANGLE, IS INTENDED TO ALERT THE USER TO THE
PRESENCE OF UNINSULATED “DANGEROUS VOLTAGE” WITHIN THE
PRODUCT’S ENCLOSURE THAT MAY BE OF SUFFICIENT MAGNITUDE TO
CONSTITUTE A RISK OF ELECTRIC SHOCK.
THE EXCLAMATION POINT WITHIN AN EQUILATERAL TRIANGLE IS
INTENDED TO ALERT THE USER TO THE PRESENCE OF IMPORTANT
OPERATING AND MAINTENANCE (SERVICING) INSTRUCTIONS IN THE
LITERATURE ACCOMPANYING THE APPLIANCE.


SERVICING PRECAUTIONS
CAUTION : Before servicing the A/V Receiver covered by this
service data and its supplements and addends, read and follow the
SAFETY PRECAUTIONS. NOTE : if unforeseen circumstances
create conflict between the following servicing precautions and any
of the safety precautions in this publication, always follow the safety
precautions.
Remember Safety First:
General Servicing Precautions
1. Always unplug the A/V Receiver AC power cord from the AC
power source before:
(1) Removing or reinstalling any component, circuit board,
module, or any other assembly.
(2) Disconnecting or reconnecting any internal electrical plug or
other electrical connection.
(3) Connecting a test substitute in parallel with an electrolytic
capacitor.
Caution : A wrong part substitution or incorrect polarity installation
of electrolytic capacitors may result in an explosion hazard.
2. Do not spray chemicals on or near this A/V Receiver or any of its
assemblies.
3. Unless specified otherwise in this service data, clean electrical
contacts by applying an appropriate contact cleaning solution to
the contacts with a pipe cleaner, cottontipped swab, or
comparable soft applicator.
Unless specified otherwise in this service data, lubrication of
contacts is not required.
4. Do not defeat any plug/socket B+ voltage interlocks with which
instruments covered by this service manual might be equipped.
5. Do not apply AC power to this A/V Receiver and/or any of its
electrical assemblies unless all solid-state device heat sinks are
correctly installed.
6. Always connect test instrument ground lead to the appropriate
ground before connecting the test instrument positive lead. Always
remove the test instrument ground lead last.
Insulation Checking Procedure
Disconnect the attachment plug from the AC outlet and turn the
power on. Connect an insulation resistance meter(500V) to the
blades of the attachment plug. The insulation resistance between
each blade of the attachment plug and accessible conductive parts
(Note 1) should be more than 1M-ohm.
Note 1 : Accessible Conductive Parts including Metal panels, Input
terminals, Earphone jacks, etc.
Electrostatically Sensitive (ES) Devices
Some semiconductor (solid state) devices can be damaged easily by
static electricity. Such components commonly are called
Electrostatically Sensitive (ES) Devices. Examples of typical Es
devices are integrated circuits and some field effect transistors and
semiconductor chip components.
The following techniques should be used to help reduce the
incidence of component damage caused by static electricity.
1. Immediately before handling any semiconductor component or
semiconductor-equipped assembly, drain off any electrostatic
charge on your body by touching a known earth ground.
Alternatively, obtain and wear a commercially available
discharging wrist strap device, which should be removed for
potential shock reasons prior to applying power to the unit under
test.
2. After removing an electrical assembly equipped with ES devices,
place the assembly on a conductive surface such as aluminum
foil, to prevent electrostatic charge buildup or exposure of the
assembly.
3. Use only a grounded-tip soldering iron to solder or unsolder ES
devices.
4. Use only an antistatic solder removal device. Some solder
removal devices not classified a “anti-static” can generate
electrical charges sufficient to damage ES devices.
5. Do not use freonpropelled chemicals. These can generate
electrical charge sufficient to damage ES devices.
6. Do not remove a replacement ES device from its protective
package until immediately before you are ready to install it. (Most
replacement ES devices are packaged with leads electrically
shorted together by conductive foam, aluminum foil, or
comparable conductive material).
7. lmmediately before removing the protective material from the
leads of a replacement ES device, touch the protective material to
the chassis or circuit assembly into which the device will be
installed.
Caution : Be sure no power is applied to the chassis or circuit, and
observe all other safety precautions.
8. Minimize bodily motions when handing unpackaged replacement
ES devices. (Normally harmless motion such as the brushing
together of your clothes fabric or the lifting of your foot from a
carpeted floor can generate static electricity sufficient to damage
an ES device.)


*%&/5*'*$"5*0/0'$0/530-4
'30/5 1"/&-
1. Power
2. Power/Standby
/Protection/Led
3. Blend
4. Info
5. Memory
6. Tuner Mode
1. +12V trigger out
2. IR in / out
3. MP input
4. CD input
5. DISC input
6. AUX input
7. TAPE input
8. REC out
9. PRE out
10.Main in
11.Sub out
12.Speaker out
13.Soft Clipping
14.ON / OFF power(AC) switch
15.Switched AC outlet
16.RS232 input
17. MP Dock data port
18.Antenna (FM)
19.Antenna(AM)
20.DAB input (230V version only)
7. Preset
8. Tune
9. VFD
10.IR Receiver
11.Record out / Zone 2 selector
12.Volume
13.Headphone
14.Speaker A & B
15.MP input
16.Input selector
17.Tone defeat
18.Tone controls
19.Balance
3&"3 1"/&-
 
   
         

           
    


SPECIFICATIONS
POWER AMPLIFIER SECTION
STEREO MODE
CONTINUOUS AVERAGE POWER 50 W (17 dBW)
OUTPUT INTO 8 OHMS OR 4 OHMS
(Min. power per channel, 20 Hz – 20 kHz,
with no more than rated distortion)
Rated Distortion 0.03%
(THD 20 Hz – 20 kHz)
Clipping power 52 W
(maximum continuous power per channel 4 and 8).
IHF dynamic headroom: at 8 ohms + 2.4 dB
at 4 ohms + 4.4 dB
IHF dynamic power
(maximum short term power per channel)
8 ohms: 160 W (20.4 dBW)
4 ohms: 220 W (22.0 dBW)
2 ohms: 270 W (23.2 dBW)
Damping factor > 100
(ref. 8 ohms 1 kHz)
Input Impedance R = 20 kohms
C = 1 nF
Input sensitivity (for rated output into 8 ohms) 780 mV
Voltage gain 29 dB
Frequency response 20 Hz – 20 kH
0.1 dB
Signal / Noise ratio, A-weighted 100 dB ref. 1 W
119 dB ref. 50 W
THD + Noise < 0.03%
(Total Harmonic Distortion, 20 Hz – 20 kHz,
from 250 mW to rated output)
SMPTE I.M. < 0.01%
(Intermodulation Distortion, 60 Hz + 7 kHz, 4:1,
from 250 mW to rated output)
IHF I.M. < 0.01%
(CCIF IM Distortion, 19 + 20 kHz at rated output)
Headphones Output Impedance 220 ohms


PREAMPLIFIER SECTION
LINE LEVEL INPUTS
(MP, CD, Disc, Aux, Tape)
Input impedance (R and C) 22 kohms + 100 pF
Input sensitivity (ref. rated power) 320mV
Maximum input signal > 4.5V
Signal / Noise ratio, A-weighted 97.0 dB ref. 1W
(from CD Input to Speakers Output, Volume Setting
for 500mV in , 8ohms 1W out)
Signal to noise ratio preamp out, IHF “A” weighted 110 dB re 500mV
Frequency response, 20 Hz – 20 kHz < +/-0.1 dB (tone defeat on)
< +/-0.2 dB (tone defeat off)
THD + Noise, SMPTE IM < 0.01% at 5 V out
LINE LEVEL OUTPUTS
Pre-amp output impedance 80 ohms
Tape output impedance Source Z + 1kohms
Maximum output level pre-amp out : > 11 V
Tape-out : > 10 V
CONTROLS
Treble +/- 5 dB at 10 kHz
Bass +/- 8 dB at 100 Hz
IR IN and OUT
Input Resistance > 10 kohms
Input Voltage Min 5 V
Output Resistance <30 ohms
TRIGGER Out
Output Current 50 mA
Output Voltage 12 V
DIMENSIONS AND WEIGHTS
Net Weight 9.4 kg ( 20.7 Ib)
Shipping Weight 11 kg ( 22 Ib)
DIMENSION (W×H×D) 435
×
149
×
396MM


CZ701
CZ704
CZ705
CZ702
CB710
COPYRIGHT C 2008 NAD C725BEE
C725 BEE POTBOARD
NAD
NAD ELECTRONIC
UL2547#26AWG
UL2468#26AWG
CB31
CZ34
UL2468 #26AWG
UL2468 #26AWG
COPYRIGHT C 2008 NAD ELECTRONICS
C725 BEE KEYBOARD
UL2468#26AWG
CZ703
CZ709
CB38
HEADPHONEBOARD
CZ46 CZ45
C725BEE STANDBY
CZ710
C725 BEE TRANSFORMER
COPYRIGHT C 2008 NAD ELECTRONIC
C725 BEE MAINBOARD
UL2468#26AWG
UL2468#26AWG
UL1015#14AWG black
UL101 5#16AWG red,whit e
CB59
3266#18AWG
3266#22AWG
CB52
CB51
1672#22AWG
CB49
CB47
CB45
18AWG UL1672#
C725 BEE POWERBOARD
COPYRIGHT C 2008 NAD ELECTRONICS
CB54
CB53
UL1672#18AW G
To AC Outlet
CB57
CB58
CB56
To Power Swicth
To AC Cord
CB55
CZ58
NAD ELECTRONIC
C725BEE AC OUTPUT BOARD
COPYRIGHT C 2008
FPC-1.25-20P-600MM
UL2468#26AWG
OUT MODULE
CB33
CZ38
CB46
IN MODULE
CB32
C725BEE RS232 BOARD
FPC-1.25-17P-220MM
CZ35
CZ36
UL1691#24AWG
UL1691#24AWG
UL2547# 26AWG
CB35
CB311 CZ37
CZ311
CZ310
TUNER MODULE
WIRING DIAGRAM


MODULE
KEY
PRO.
POWERAMP
LINEAR
+-46V
SWITCHING POWER
+5.5V
ISC TRIG
AC DET
CLIPPING
SOFT
POWERBOARD SECTION
SPEAKER B
SPEAKER A
LINEAR
+5.5V
RELAY
RELAY
RL12/2
RL12/1
MAINBOARD SECTION
KEYBOARD SECTION
UNIT PRO.
VFD
IP SEL
DEFEAT
MODULE
PREAMP
BALANCE
CB32
RT34
CONTROL
RT32&RT31
RL39
TONE
ISC
CIRCUIT
RT33
CONTROL
VOLUME
TONE
MCU
IC703
TONE DEFEAT
STANDBY
SPEAKER A
SPEAKER B
REC OUT
RECOUT SELECT SWITCH
IC31 TC9164
MAIN IN
PREOUT
RELAY RL310
SUBOUT
2SK303
Q301
INPUT SELECTOR
DISC
TUNE
MP
AUX
TAPE
CD
IC32
HCF4094
BLOCK DIAGRAM


2
31
IC702
IR RECEIVER
FM-6038TM2-5AN
P10257
P91
1
P90
2
CNVSS
3
P87/XCIN
4
P86/XCOUT
5
RESET
6
XOUT
7
VSS
8
XIN
9
VCC
10
P85/NMI
11
P84/INT2
12
P83/INT1
13
P82/INT0
14
P81
15
P80
16
P77
17
P76
18
P75
19
P74
20
P73
21
P72
22
RXD2/P71
23
TXD2/P70
24
TXD1/P67
25
RXD1/P66
26
P65
27
P64
28
P33
29
P32
30
P31
31
P30
32
TXD0/P6333
RXD0/P62 34
P6135
P6036
P27 37
P26 38
P2539
P2440
P2341
P22 42
SCL/P2143
SDA/P2044
P1745
P1646
P15 47
P03 48
P0249 P01 50 P00 51
P10752 P10653 P105 54 P104 55 P103 56 P101 58
AVSS 59
P100 60
VREF 61
AVCC 62
P93 63 P9264
IC703
M30281F6HP
+5.8V
1
2
CZ707
CON2
1
2CZ706
CON2
RESET
1GND
2RESET
3
VDD 5
MR 4
IC704
TPS3825-50DBVT
Y701
18.432MHz
R774
1MEG
R773
33
DGND
A01
A12
A2 3
Vss 4 SDA
5SCL
6WP
7Vdd
8
IC705
24C16
1 2 3 4 5 6 7 8 9
10 11 12 13 14 15 16 17 18 19 20
CZ702
TO PREAMP SCH
DGND
STR 1
D2
CLK 3
OE 15
VCC 16
Q1
4
Q2
5
Q3
6
Q4
7
Q5
14
Q6
13
Q7
12
Q8
11
QS
9
QS
10
GND
8
IC707
CD4094
R710
R713
A1
C2
B3
IC706
EC12E1220801-F20
IR OUT IR IN OP SEL DATA OP SEL CLK OP SEL STB2 Unit Protect IP SEL STB IP SEL DATA IP SEL CLK
+5.8V
+5.8V
DGND
F1 1 F269
16G52 Q1653
TSB54 TSA 55
DA56 CP 57 CS58
RESET 59
OSC60
VDD 61
VH62
PGND 63
LGND 64
IC701
16-BT-130GINK
OP SEL CLK OP SEL DATA OP SEL STB1
R763
10
R764
10
C1+ 1
V+2
C1- 3
C2+4
C2-5
V-6
T2OUT 7
R2IN 8 R2OUT
9
T2IN
10
T1IN
11
R1OUT
12
R1IN
13
T1OUT
14
GND
15
VCC
16
IC709 SP232EEP-L
12 34 56 78 910
1112 1314
CZ708
R701 47K
CE
CNVss
Reset
R786
15k
Q702
C1815
D722
1N4148
D723
1N4148
1A
1B
1Y
2A
2B
2Y
GND3Y
3A
3B
4Y
4A
4B
VCC
IC710
74HC86
DGND
STR 1
D2
CLK 3
OE 15
VCC 16
Q1
4
Q2
5
Q3
6
Q4
7
Q5
14
Q6
13
Q7
12
Q8
11
QS
9
QS
10
GND
8
IC711
CD4094
1 2 3 4 5 6 7
CZ711
TO POWER BOARD
Q734
C1815
R796 47
R797 47
R798 47 R799 47 R768 47 R769 47 R770 47
TUNER MODULE
KEY
TO DAB MODULE
TO IPOD
TO STANDBY BOARD
TO MP BOARD TO MP LED D719
MCU CONNECTION DIAGRAM


MCU
30281FA
KEY BOARD IC703
11
I/O
Ports
Internal Peripheral Functions
Timer
TimerA0 (16 bits)
TimerA1 (16 bits)
TimerA2 (16 bits)
TimerA3 (16 bits)
TimerA4 (16 bits)
Timer B0 (16 bits)
Timer B1 (16 bits)
Timer B2 (16 bits) Watchdog Timer
A-D converter
(10bits x 13 channels)
System Clock Generator
Xin-Xout
Xcin-Xcout
Ring Oscillator
M16C/60 series 16-bit CPU Core
R0LR0H
R1LR1H
R2
R3
A0
A1
FR
R0LR0H
R1LR1H
R2
R3
A0
A1
FB
Registers
SB
PC
ISP
USP
Program Counter
Stack Pointers
INTB
Vector Table
FLG
Flag Register
Memory
Multiplier
Flash ROM
RAM
3-phase PWM
Port P0
4
Port P1
3
Port P2
8
Port P3
4
Port P6
8
Port P7
8
Port P8
8
Port P9
4
Port P10
8
Timer S
Input Capture (8 channels)
Output Compare (8 channels)
Flash ROM
(Data Flash)
U(S)ART/SIO (channel 0)
Serial Ports
U(S)ART/SIO (channel 1)
U(S)ART/SIO/I
2
C/IEbus
(channel 2)
Multi-master I
2
C BUS
SIO (channel 3)
PLL frequency synthesizer
Low voltage detect
DMAC (2 channels)

CD4094
KEYBOARD:IC707 IC711
MAINBOARD:IC32


1
2
3
4
5
6
7
98
01
11
21
31
41
51
61+1C
+V
-1C
+2C
-2C
-V
TUO2T
TUO2RNI2R
NI2T
NI1T
TUO1R
TUO1T
NI1R
DNG
CCV
keyboard,SP232EEP
IC709
smhoK5
smhoK5
smhoK004
smhoK004
Fu1.0
Fu1.0 fu1.0
Fu1.0
Fu01
TUPNIV5+
CCV
NI1T
NI2T
TUO1R
TUO2R NI2R
NI1R
TUO1T
TUO2T
2T
1T
1R
2R
51DNG
1
2
3
4
5
6
7
89
01
11
21 31
41
61
-V
+V
+1C
-1C
-2C
+2C
V01+otV5+
relbuoDegatloV
retrevnIegatloV
V01-otV01+


24C16
KEY BOARD IC705
PIN CONFIGURATION
FUNCTIONAL BLOCK DIAGRAM
WP
8-Pin PDIP
1
2
3
4
8
7
6
5
A0
A1
A2
GND
VCC
WP
SCL
SDA


PROCESSOR SUPERVISORY CIRCUIT
TPS3825
KEY BOARD IC704
BLOCK DIAGRAM:
Vdd
_
+
Watchdog
Timer Logic Reset Logic
Reset†
Reset
MR‡
WDI
Transition
Detector


74HC86 KEY BOARD IC710
11
Quad 2-input EXCLUSIVE-OR gate
PIN DESCRIPTION
PIN NO. SYMBOL NAME AND FUNCTION
1, 4, 9, 12 1A to 4A data inputs
2, 5, 10, 13 1B to 4B data inputs
3, 6, 8, 11 1Y to 4Y data outputs
7 GND ground (0 V)
14 VCC positive supply voltage
Fig.1 Pin configuration. Fig.2 Logic symbol. Fig.3 IEC logic symbol.


TC9164
MAINBOARD:IC31
PIN CONNECTION:
BLOCK DIAGRAM :


TNY274
POWERBOARD:IC51
PIN CONNECTION :
BLOCK DIAGRAM:


4. Connect a DC voltmeter toTP3 and TP4 ,adjust VR12/VR13 for 6mV reading on voltmeter.
3. Connect a DC voltmeter toTP1 and TP2 ,adjust VR22/VR23 for 6mV reading on voltmeter.
2. Input a high voltage signal such as 5V from CD input.
5. Adjusting VR302,make R channel output become to the lowest level by same way.
4. Observing the oscilloscope,adjust VR301,make the output of speakers become to the
Repeat procedure A,B and C for the lowest volume level, idling current alignment
Adjust the pot VR3 to make the DC voltage of the point of TP5 to the same as TP6
VR303
VR301
VR302
VR304
VR13
TP4
II. FINAL ADJUSTMENT
and ISC original level respectively.
B. IDLING CURRENT
A. LOWEST VOLUME ADJUSTMENT
C.ISC CIRCUIT ORIGINAL ADJUSTING
2. Running 5 minutes with no signal
1. Power on
3. Connect a oscilloscope to L channel binding posts.
1. Tune the volume pot to lowest state.
C725BEE MAINBOARD
TP3
TP2
TP1
VR23
VR12
VR22
VR3
TP5 TP6
ALIGNMENT PROCEDURES
lowest level.
I. INITIAL


D52
6V2 C54 47uF/25V
C535
4n7/400V
C51
10n/250V
s2
+
s1
-
D51
KBU8D
C52
10n/250V
s2
+
s1
-
D55
KBU8D
C517
15000uF/50V 10%
C518
15000uF/50V 10%
Q517
A1015
D531
TIC116D
R558
1K
R563
22K
R561
100
R562
1K
R560
1K
R559 1K
R565
100
R564 22K
R531
0.05/3W 5% CE
R532
220
Q510
A1015
Q59
A1015
R534
2K2
R533
1M
Q519
A1015
R566
4K7
D513
1N4004
R544
22K
C523
3300u/50V
C524
2200u/50V
1
2
3
4
CB54
1
2
3
CB55
!
!
F51
I-V
AC DET.
TRIG
C725BEE POWERBOARD
10% 10%
D510
DB105
1
2
3
CB56
1
3
CB57
1
2
3
4
5
CB51
1 2 3 4 5 6 7 8 9 10
CB52
1
2
3
CB58
36.4V
36.4V
0V
28.5V
28.5V
R567
15K
C53
330u/63V
C55
10uF,63V
Q58
KSC2690
R568
3K3
1
2
3
4
5
6
7
CB53
To Main board
D54
DB104
DGND
C56
0.22uF
D56
DB104
PGND
DGND
R569
330K
C531
10uF/400V
UV
1
BP
2
D
4S5
S6
S7
S8
IC51
TNY274
C534 10nF/1KV
R572
100K/1W D58
FR107/UF4006
T51
EE16
D59 SR540
C536
0.1uF C533
330uF/10V
IC53 PC817
PGND
C530
0.1uF/16V
R570 100
R571 510 DGND
RL51
Relay-SPST
D533
1N4148
Standby
C539
4N7/400V
R574
4K7
Q522
C1815
R575
4K7
DGND
+5.5V
Standby
DGND
C544
10nF
+5.5V L52
10uH
C545
330uF/10V
R576
0.33,1/4W
C546 2.2nF/250V,Y1
+46V-46V
+39V
+37V
-37V
Q518
C1815
Q520
C1815
D53
39V
D57 4V7
D532
TIC116D
AC POWER CORD
1 2 3 4 5 6 7 8 9
10
CZ52
2.6V 40V
SW52
POWER SWITCH
BLUE
2.6V
1
3
CZ57
YELLOW
!
1
2
3
CZ55
!
0V
RED
1
2
3
CZ58
!
ORANGE
BLUE
!
BLACK
0V
!
YELLOW
!
!
!
1
2
3
CZ56
!
BLACK
1
1
2
2
AC OUTLET
1
2
3
4
5
CZ51
GRAY
PURPLE
1
2
3
4
5
6
7
CB59
To Key board
DGND
+39V
To Main board
1
122
33
4
4
L51
FILTER INDUCTOR,48mH
!
T2AL/250V For 230V Mains Version
T4AL/250V For 120V Mains Version
!
DGND
C725BEE TRANSFORMER
17V 10V 0V
D538
DB104
D536
DB104 IN
IC55 LM7805M
D537
DIODE
C551
100uF/16V
C552
4700uF/25V
C550
0.1uF
DGND
C553
0.1uF C554
100uF/25V
C549
2200uF/35V
IN
IC52
LM7812M
DGND
+12V
+12V
+5.6V
Transformer Protect Det.
