NAD T752 User manual

NAD
SERVICE MANUAL
T 752
T 752
AV SURROUND
SOUND RECEIVER
AV SURROUND
SOUND RECEIVER
DRAFT DATE: 08 OCT, 2002

2
SAFETY INFORMATION

3
SERVICE SAFETY PRECAUTIONS
1. Replacing the fuses
CAUTION:
FOR CONTINUED PROTECTION AGAINST THE RISK OF FIRE REPLACE ONLY WITH SAME TYPE OF
FUSE.
Reference Designator Part Number Description
F751*AH 33-0160001-00-48 Fuse 8A 250V Time Lag 5x20 MM UL/CSA
F751*C 33-0131002-00-48 Fuse 5A 250V Time Lag 5x20 MM SEMKO/VDE
F752*AH 33-0111006 -00-48 Fuse 1.6A 250V Time Lag 5x20 MM
UL/CSA/VDE/SEMKO
F752*C 33-0151006 -00-48 Fuse 800mA 250V Time Lag 5x20 MM
UL/CSA/VDE/SEMKO
NOTE:
<*AH > : USA, CANADIAN MODEL ONLY.
<*C > : EUROPEAN MODEL ONLY.
2. Safety check out
(Only U.S.A. model)
Before returning the product to the customer, make leakage current or resistance measurements to determine
that exposed parts are acceptably insulated from supply circuit.
CONTENTS
DESCRIPTION PAGE
SPECIFICATIONS ........................................................................................................................... 4 - 5
REAR PANEL / FRONT PANEL VIEW ................................................................................................. 6
DISASSEMBLY INSTRUCTIONS ......................................................................................................... 7
WIRING DIAGRAM ............................................................................................................................... 8
BLOCK DIAGRAM ................................................................................................................................ 9
ADJUSTMENT POINTS DIAGRAM / AMPLIFIER ADJUSTMENT ..................................................... 10
PCB LAYOUT ............................................................................................................................... 11 - 23
SCHEMATIC DIAGRAM .............................................................................................................. 24 - 36
IC BLOCK DIAGRAM ................................................................................................................... 37 - 45
EXPLODED VIEW .............................................................................................................................. 46
EXPLODED VIEW PARTS LIST .................................................................................................. 47 - 48
ELECTRICAL PARTS LIST .......................................................................................................... 49 - 58
PACKING DIAGRAM .......................................................................................................................... 59
Parts marked with the symbol are critical with regard to the risk of fire and electric shock.
Replace only with parts recommended by the manufacturer.

4
SPECIFICATIONS
POWER AMPLIFIER SECTION
Rated distortion (Rated power level into 8 ohms, THD 20 Hz-20 kHz FL/C/FR) ≤0.1 %
(Rated power level into 8 ohms, THD 20 Hz-20 kHz SL/SR) ≤0.1 %
Input Sensitivity (ref. 8 ohms, 1 kHz) 200 ± 20 mV
S/N Ratio (A-wtd, 1kHz, 1 W, 8 ohm, SL/SR) ≥≥
≥≥
≥- 80 dB
(A-wtd, 1kHz, 80 W, 8 ohm, SL/SR) ≥≥
≥≥
≥- 96 dB
Frequency Response (20 Hz - 20 kHz) 0 ± 0.8 dB
Channel Balance (1 dB to -40 dB, 1 kHz) ≤2 dB
(-41 dB to -50 dB, 1 kHz) ≤3 dB
Audio muting at 1 kHz ≥≥
≥≥
≥55 dB
Subwoofer out, 500 mV in (THD at 2 V O/P, 100 Hz) ≤0.5 %
Crosstalk (500 mV input, 10 W, 1 kHz) ≥≥
≥≥
≥-70 dB
Controls
Bass (at 500 mV in, 1 W out, 100 Hz) ± 10 dB ± 2 dB
Treble (at 500 mV in, 1 W out, 10 kHz) ± 10 dB ± 2 dB
DOLBY DIGITAL SECTION
Channel Difference(FL ref. Track 30) ± 1.2 dB
Frequency Response @Dolby config.2SL Track 46 200 - 20 kHz ± 0.8 dB
SR Track 47 200 - 20 kHz ± 0.8 dB
C Track 44 200 - 20 kHz ± 0.8 dB
Harmonic Distortion (1 W, Audio LPF, Dolby Config.1) FL Track 65 997 Hz ≤0.08 %
FR Track 67 997 Hz ≤0.08 %
SL Track 68 997 Hz ≤0.08 %
SR Track 69 997 Hz ≤0.08 %
C Track 66 997 Hz ≤0.08 %
S/N Ratio (31 for O/P 1 W, Track 35) CCIR / ARM ≥≥
≥≥
≥65 dB
Audio LPF ≥≥
≥≥
≥70 dB
A-wtd ≥≥
≥≥
≥70 dB
Channel Separation (1 W, 20 kHz LPF) Track 65 997 Hz ≥≥
≥≥
≥75 dB
DOLBY PRO LOGIC II SECTION
Frequency Resporse
I/P mode : L, R : 1 V in, 1 W, Ch L/R 40 Hz 0 ± 1.5 dB
20 Hz 0 ± 0.8 dB
I/P mode : L, R : 1 V in, 1 W, Ch C 300 Hz 0 ± 0.8 dB
20 Hz 0 ± 0.8 dB
I/P mode : L, R : 1 V in, 1 W, Ch SL/SR 40 Hz 0 ± 1.5 dB
20 Hz -3 ± 1.0 dB
S/N Ratio (200 mV in, 1 W, A-WTD w/ 1 k termination)
I/P mode : L, R : 1 kHz, Ch L/R ≥≥
≥≥
≥65 dB
I/P mode : L, R : 1 kHz, Ch C ≥≥
≥≥
≥65 dB
I/P mode : L, R : 1 kHz, Ch SL/SR ≥≥
≥≥
≥65 dB
THD (2.2 V in, 1 W, w/ 80 kHz LPF, 1 kHz) ≤0.2 %

5
AM TUNER SECTION
Input level is expressed as the reading in open circuit
of 75-ohm source impedance signal generator
Usable sensitivity (999/1000 kHz) ≤≤
≤≤
≤30 dBuv
S/N Ratio (5 mV in) ≥≥
≥≥
≥30 dB
THD (5 mV in) ≤≤
≤≤
≤3 %
IF Rejection (450 kHz) ≤≤
≤≤
≤36 dB
Image Rejection (F+2xIF) ≥≥
≥≥
≥28 dB
Selectivity ≥≥
≥≥
≥17 dB
Output 110 ± 20 mV
Loop sensitivity (20 dB S/N)
999/1000 kHz ≤≤
≤≤
≤66 dB
603/600 kHz ≤≤
≤≤
≤66 dB
1404/1400 kHz ≤≤
≤≤
≤66 dB
Frequency Response (100 - 2.3 kHz, 5 mV) ± 6 dB
FM TUNER SECTION *C *AH
Input level is expressed as the reading in open circuit
of 75-ohm source impedance signal generator
Usable sensitivity (98 MHz) ≤≤
≤≤
≤15 dBuv ≤≤≤≤≤15 dBuv
S/N Ratio (60 dB, IHF wtd) Mono ≥≥
≥≥
≥65 dB ≥≥
≥≥
≥65 dB
Stereo ≥≥
≥≥
≥60 dB ≥≥
≥≥
≥60 dB
Frequency Response (20 Hz - 15 kHz, 60 dBm) 0 ± 1.5 dB 0 ± 1.5 dB
Channel Separation (60 dBm) 100 Hz ≥≥
≥≥
≥30 dB ≥≥
≥≥
≥30 dB
1 Hz ≥≥
≥≥
≥35 dB ≥≥
≥≥
≥35 dB
10 Hz ≥≥
≥≥
≥20 dB ≥≥
≥≥
≥25 dB
Alternate Channel Selectivity (40 dBm, ± 400 kHz) ≥≥
≥≥
≥60 dB ≥≥
≥≥
≥45 dB
Capture Ratio (40 dBm) ≤≤
≤≤
≤3 dB ≤≤
≤≤
≤3 dB
AM Suppression (60 dBm, 100% Mod. FM, 30% Mod. AM) ≥≥
≥≥
≥40 dB ≥≥
≥≥
≥40 dB
Image Rejection (119.4 MHz) ≥≥
≥≥
≥65 dB ≥≥
≥≥
≥65 dB
I.F. Rejection (10.7 MHz) ≥≥
≥≥
≥78 dB ≥≥
≥≥
≥65 dB
Pilot Suppression (60 dBm) ≥≥
≥≥
≥60 dB ≥≥
≥≥
≥60 dB
THD (60 dBm, L=R 75 kHz for AH, 40 kHz Dev for C) Mono ≤≤
≤≤
≤0.8 % ≤≤
≤≤
≤0.8 %
Stereo ≤≤
≤≤
≤1 % ≤≤
≤≤
≤1 %
Auto-Search Sensitivity On ≥≥
≥≥
≥24 dBuv ≥≥≥≥≥24 dBuv
Off ≤≤
≤≤
≤15 dBuv ≤≤≤≤≤15 dBuv
RDS decode Sensitivity ≤≤
≤≤
≤26 dBuv -
PHYSICAL SPECIFICATIONS
Dimensions (Width x Height x Depth) 435 x 133 x 349 mm
Net Weight 14.40 Kg (31.68 lbs)
Shipping Weight 16.00 Kg (35.20 lbs)

6
12 345678 9
19
20 11 12 13 14 15 16 17 18
10
23
1
15 1214
56 8
11
9
1
0
16
74
13
FRONT PANEL
REAR PANEL / FRONT PANEL VIEW
REAR PANEL
1. FM & AM ANTENNA
2. MAIN IN / AUDIO PRE-OUTS /
SUBWOOFER OUT
3. MONITOR OUT
4. CD INPUT
5. DISC INPUT
6. IR INPUT & OUTPUT
7. COMPONENT VIDEO IN & COMPONENT
VIDEO OUT
8. SOFT CLIPPING ON/OFF
9. SWITCHED POWER OUTLETS
10. AC POWER CORD
11. DIGITAL AUDIO INPUTS & DIGITAL AUDIO
OUTPUT
12. FRONT, CENTER & SURROUND SPEAKERS
13. 12V TRIGGER INPUT & OUTPUT
14. VIDEO 1 - VIDEO 5 (AUDIO & VIDEO)
15. TAPE INPUT & OUTPUT
16. 7.1 CHANNEL INPUTS
1. POWER
2. STAND-BY
3. AM / FM
4. DISPLAY
5. MEMORY
6. FM MUTE / MONO
7. PRESET DOWN / UP
8. SEARCH DOWN / UP
9. VFL DISPLAY
10. VOLUME
11. VIDEO & AUDIO
12. TAPE MONITOR
13. DIGITAL AUDIO SELECTOR
14. EXT. 7.1
15. SURROUND MODE
16. LEVELS
17. TONE CONTROLS
18. TONE DEFEAT
19. VIDEO 6 INPUT
20. PHONES

7
DISASSEMBLY INSTRUCTIONS
1. Remove machine screws M4.0 x 8.0 (1to 6) from the side panels.
Remove tapping screw 3.0 x 8.0 (7to 10) from the back panel.
Refer to Figure No. 1.
1
4
5
6
7
8
9
10
2
3
2. Pull both sides of the TOP COVER slightly outwards 11 and tilt approx. 35 ° and then remove
in the
direction as indicated by the arrow 12. Refer to Figure No. 2.
Figure No. 1
12
11
11
Figure No. 2

8
2-
0116
4
35
-
00
-
95
CABLE A
SS
Y 1 WAY
#
1
6
U
L 1
6
72 BR
O
WN L=4
00
M
M
C
ABLE A
SS
Y
3
WAY
S
#
2
6
U
L2
8
77 L=1
50
8
2-
03
2
6135
-
0
7-
98
VIDE
O
6
INP
U
T B
O
ARD
J
72
1B
J
7
09B
T
O
S
EC
O
NDARY TRAN
S
F
O
RMER
TO
TRAN
S
F
O
RMER
T
HERM
OS
TAT
TO
S
E
CO
NDARY TRAN
S
F
O
RME
R
TO
PIRMARY
T
RAN
S
F
O
RMER
8
2-142
6
1
35
-
00
-
98
CABLE A
SS
Y 14 WAY
S
#
2
6
2
.
5
P
U
L2
8
77 L=42
0
mm
S
EC
O
NDARY B
O
AR
D
3
.
96
P
U
L
1015
L=
90
mm
8
2-
08
1
8
2
35
-
00
-
98
J
7
83A
J
7
8
2
A
J
7
8
4
A
J
7
81A
P
O
WER
S
WIT
CH
B
O
ARD
A
C
ABLE A
SS
Y 1 WAY
#
1
6
U
L
16
72 BL
U
E L=
100
8
2-
0116
4
36
-
1
2-
95
(
FOR AH VESION ONLY
)
CABLE A
SS
Y 1 WAY
#
1
6
U
L1
6
72 BR
O
WN L=1
00
m
m
(
FOR AH VE
S
ION ONLY
)
PO
WER
SU
PPL
Y
B
O
AR
D
8
2-
0
11
6
4
38
-
03
-
95
J30
4
B
8
2-
08
2
6135
-
00
-
98
8
2-
0116
4
35
-
01
-
95
J
7
56
U
L
16
72 BL
U
E L=4
00
M
M
CABLE A
SS
Y 1 WAY
#
1
6
CABLE A
SS
Y
8
WAY
S
#
2
6
2
.
5
P
U
L2
8
77 L=4
80
mm
J
7
58
J
7
58A
L
J
7
59
N
J
7
57
8
2-
03
2
6
1
35
-
03
-
98
C
ABLE A
SS
Y
3
WAY
S
#
2
6
2.
5
P
U
L2
85
4 L=1
50
mm
TRI
GG
ER B
O
ARD
2
.
5
P
U
L2
8
77 L=
500
mm
8
2-1
0
2
6
1
35
-
0
1-
98
C
ABLE A
SS
Y 1
0
WAY
S
#
2
6
8
2-
03
2
6135
-
0
4-
98
J
2
03A
J
7
0
2
A
P1.2
5
L=2
00
m
m
FFC CABLE 2
0
PIN
S
36
-2
0
2
8
2
0
1-71-
92
C
ABLE A
SS
Y
3
WAY
S
#
2
6
2
.5P UL2877 L=400mm
J
7
53B
KEYB
O
AR
D
FFC CABLE 2
8
PIN
S
36
-2
8
2
8
2
01
-7
1
-
9
2
P
1
.25 L=200m
m
J
7
1
7
A
J
7
05A
C
ABLE A
SS
Y
8
WAY
S
#
2
6
2
.
5
P
U
L2
8
77 L=4
80
mm
8
2-
08
2
6135
-
00
-
98
8
2-
06
2
6135
-
03
-
98
C
ABLE A
SS
Y
6
WAY
S
#
2
6
2
.
5
P
U
L2
8
77 L=4
80
mm W
/
H
OUS
IN
G
J
7
81
B
J503
B
J
722
B
J611B
J
7
8
2
B
J
7
09A
CABLE ASSY 12 WAYS #26
8
2-
1
22
6135
-
00
-
98
2.
5
P
U
L2
8
77 L=24
0
CABLE A
SS
Y 3 WAY
S
#2
6
8
2-
03
2
6135
-
05
-
98
MAIN B
O
AR
D
J
721
A
J50
2
B
J
722
A
8
2-
0318
2
35
-
00
-
98
C
ABLE A
SS
Y
3
WAY
S
#
1
8
3
.
96
P
U
L
1015
L=
100
mm
J30
4
A
8
2-
0
22
6
1
35
-
00
-
98
C
ABLE A
SS
Y 2 WAY
S
#
2
6
U
L2
8
77 L=
150
mm
J
7
55A
A
U
DI
O
B
O
AR
D
8
2-
03
2
6
1
35
-
0
2-
98
J801B
J
7
0
4
A
J
72
0A
J50
1
B
J
7
18A
J
2
03B
F
FC CABLE 2
8
PIN
S
P1.2
5
L=
80
mm
CABEL ASSY 4 WAYS # 26 2.5P UL2877 L=200mm
8
2-
03
2
6135
-
06
-
98
2
.
5
P
U
L2
85
4 L=2
50
mm
8
2-
0
42
6135
-
00
-
98
C
ABLE A
SS
Y
3
WAY
S
#
2
6
3
6-2828800-71-92
J61
2
B
CABLE A
SS
Y 12 WAY
S
#
2
6
2.
5
P
U
L2
8
77 L=12
0
m
m
8
2-12241
35
-
0
2-
98
J
7
19A
J50
2
A
J503A
J501A
F
FC CABLE 2
0
PIN
S
P1.2
5
L=12
0
mm
C
ABEL A
SS
Y
6
WAY
S
#
2
6
2.
5
P
U
L1
533
X1C L=
350
mm
36
-2
0
2
8
121-71-
9
2
8
2-
06
2
6135
-
0
2-
98
J
414B
C
ABLE A
SS
Y
5
WAY
S
#
1
8
3
.
96
P
U
L1
0
1
5
L=2
50
mm
F
FC CABLE 17 PIN
S
P1.2
5
L=1
50
mm
8
2-
0518
2
35
-
00
-
98
36
-172
8
1
5
1-71-
9
2
J
4
1
4
A
M50
4
TO
FAN
TO
THERMI
S
T
O
R
T
U
NER
CO
MP
O
NENT VIDE
O
B
O
ARD
J
1
009
A
J
71
9B
J
71
8B
J6
11
A
J6
14
B
P
RE-
OU
T B
O
AR
D
J
717
B
8
2-
10
2
6135
-
06
-
98
CABLE ASSY 10 WAYS #26 2.5P UL2877L=50mm
M
U
LTI-CHANNEL B
O
AR
D
FR
O
NT/CENTER
AMPLIFIER B
O
AR
D
S
-VIDE
O
B
O
AR
D
D
I
G
ITAL B
O
ARD
D
S
P B
O
AR
D
LED B
O
AR
D
SU
RR
OU
N
D
AMPLIFIER B
O
AR
D
VIDE
O
B
O
AR
D
WIRING DIAGRAM
8a

Part No. Description Location Start End
Normal Front and Center Amp Board
82-1224135-02-98 CABLE ASSY 12 WAYS AWG=26 2.5P UL2877 L=120mm J503A FR & C Amp board Surr Amp Board
Normal Surround Amp Board
82-0318235-03-98 CABLE ASSY 3 WAYS AWG=18 3.96P UL1007 L=180mm J504B Surr Amp Board FR & C Amp board
82-0818235-00-98 CABLE ASSY 8 WASY AWG=18 3.96P UL1015 L=90mm J781B Surr Amp Board Secondary Board
Normal Component Video Board
82-0826135-01-98 CABLE ASSY 8 WAYS AWG=26 2.5P UL2877 L=450mm J414B Component Video Board S-Video Board
Normal Digital Input Board
82-0426135-02-98 CABLE ASSY 4 WAYS AWG=26 2.5P UL2877 L=500mm J1010A Digital Input Board DSP Board
82-1226135-03-98 CABLE ASSY 12 WAYS AWG=26 2.5P UL1533 L=500mm J1009A Digital Input Board DSP Board
Normal Keyboard
82-0118435-00-98 CABLE ASSY 1 WAY AWG18 UL1007 BLACK L=100mm W/ RING TERMINAL J201 Keyboard Subfascia
82-0326135-04-98 CABLE ASSY 3 WAYS AWG=26 2.5P UL2877 L=400mm J753B Keyboard Power Supply Board
82-0426135-00-98 CABEL ASSY 4 WAYS AWG=26 2.5P UL2877 L=200mm J702A Keyboard Main Board
Normal LED Board
82-0326135-07-98 CABLE ASSY 3 WAYS AWG=26 UL2877 L=150mm J204A LED Board Keyboard
Normal Main Board
82-0326135-05-98 CABLE ASSY 3 WAYS AWG=26 2.5P UL2877 L=320mm J722A Main Board Surr Amp Board
82-0326135-06-98 CABLE ASSY 3 WAYS AWG=26 2.5P UL2854 L=250mm J715A Main Board DSP Board
82-0626135-03-98 CABLE ASSY 6 WAYS AWG=26 2.5P UL2877 L=480mm W/HOUSING J721A Main Board Video-6 Board
82-0826135-00-98 CABLE ASSY 8 WAYS AWG=26 2.5P UL2877 L=480mm J709A Main Board Video-6 Board
82-1226135-00-98 CABLE ASSY 12 WAYS AWG=26 2.5P UL2877 L=240mm J502B Main Board FR & C Amp board
Normal Speaker Board
82-0318235-02-98 CABLE ASSY 3 WAYS AWG=18 3.96P UL1007 L=120mm J801B Speaker Board Surr Amp Board
82-0518235-02-95 CABLE ASSY 5 WAYS AWG=18 3.96P UL1007 L=350mm J786B Speaker Board Secondary Board
82-0518235-03-98 CABLE ASSY 5 WAYS AWG=18 3.96P UL1007 L=300mm J501B Speaker Board FR & C Amp board
Normal Pre-Out Board
82-0326135-02-98 CABLE ASSY 3 WAYS AWG=26 2.5P UL2854 L=700mm J611A Pre-Out Board Surr Amp Board
82-0626135-02-98 CABEL ASSY 6 WAYS AWG=26 2.5P UL1533X1C L=350mm J612A Pre-Out Board FR & C Amp board
82-1026135-06-98 CABLE ASSY 10 WAYS AWG=26 2.5P UL2877L=50mm J614B Pre-Out Board Multi-Channel Board
82-1026135-06-98 CABLE ASSY 10 WAYS AWG=26 2.5P UL2877L=50mm J615B Pre-Out Board Multi-Channel Board
Normal Power Switch Board
82-0116435-00-95 CABLE ASSY 1 WAYS AWG=16 UL1672 BROWN L=370mm J757B Power Switch Board Power Supply Board
82-0116435-01-95 CABLE ASSY 1 WAYS AWG=16 UL1672 BLUE L=370mm J756B Power Switch Board Power Supply Board
MODEL: T752
CABLE HARNESS CROSS REFERENCE
8b

Normal Secondary Board
82-1426135-00-98 CABLE ASSY 14 WAYS AWG=26 2.5P UL2877 L=420mm J782A Secondary Board Main Board
Normal Trigger Board
82-0326135-03-98 CABLE ASSY 3 WAYS AWG=26 2.5P UL2854 L=150mm J304B Trigger Board Audio Board
82-0826135-00-98 CABLE ASSY 8 WAYS AWG=26 2.5P UL2877 L=480mm J350A Trigger Board Keyboard
Normal Video-6 Board
82-0118435-00-98 CABLE ASSY 1 WAY AWG18 UL1007 BLACK L=100mm W/ RING TERMINAL P4401 Video-6 Board Chassis
Casing
36-1728201-71-26 FFC CABLE 17 PINS P1.25 L=200mm J720C Main Board Tuner
36-2028121-71-92 FFC CABLE 20 PINS P1.25 L=120mm J604C DSP Board Multi-Channel Board
36-2028201-71-92 FFC CABLE 20 PINS P1.25 L=200mm J713C Main Board Keyboard
36-2828201-71-92 FFC CABLE 28 PINS P1.25 L=200mm J714C Main Board Keyboard
36-2828800-71-92 FFC CABLE 28 PINS P1.25 L=80mm J203C Keyboard DSP Board
82-0116436-12-95 CABLE ASSY 1 WAY AWG=16 UL1672 BROWN L=100mm J759 AC Outlet Power Supply Board
82-0116438-03-95 CABLE ASSY 1 WAY AWG=16 UL1672 BLUE L=100mm J758 AC Outlet Power Supply Board
8c

9
OS
D
L
C747
63
Pin
4
14
B
E
A
C
S
peaker
O
ut
p
ut
O
ut
p
ut
Sp
eaker
Pin ( ST/MO, Mute, S Meter )
C
E/Data/Clk
,
RDSbus
V
FD Driver
CPUs
S
tere
o
m
od
e
AC3
m
od
e
M
ulti Ch in
by
CPU
co
ntr
o
l
4966
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BLOCK DIAGRAM
U201 A/VR (A/V Receiver)
U202 VFD

10
AMPLIFIER ADJUSTMENT
Idle Current
1. Rotate R522 fully clockwise.
2. Connect DC millivoltmeter to P501 (i.e. Across half of R523, 0.22 Ohm resistor).
3. Turn on the unit.
4. Adjust R522 for 1mV reading on voltmeter.
5. Leave power on for at least 5 min, and check for idle current again.
6. Repeat for other channels.
CHANNEL JUMPER VR
FL P503 R571
FR P502 R545
C P501 R522
SL P801 R835
SR P802 R836
ISC Sensitivity
1. Connect 8 ohm loading to all channels.
2. Rotate R886 fully clockwise.
3. Load all channels at full power using 1kHz sine wave.
4. At this time, monitor the THD of the output. Clipping should occur before full power achieved.
5. Rotate R886 counter-clockwise slowly until the THD just below 0.1%.
6. The procedure is finish at this step.
7. Load all channels at full power using 1kHz sine wave with 4 ohm load.
8. The clipping power(at THD 0.1%) should less than 85W.
ADJUSTMENT POINT DIAGRAM
FRONT/CENTER AMPLIFIER BOARD
SURROUND AMPLIFIER BOARD

11
PCB LAYOUT
AUDIO BOARD - COMPONENT SIDE
AUDIO BOARD - COPPER SIDE

12
COMPONENT VIDEO BOARD - COMPONENT SIDE
COMPONENT VIDEO BOARD - COPPER SIDE
DIGITAL BOARD - COMPONENT SIDE SIDE
DIGITAL BOARD - COPPER SIDE

13
DSP BOARD - COPPER SIDE
DSP BOARD - COMPONENT SIDE

14
FRONT/CENTER AMPLIFIER BOARD

15
SURROUND AMPLIFIER BOARD

16
KEY BOARD - COMPONENT SIDE KEY BOARD - COPPER SIDE

17
MAIN BOARD

18
MULTI-CHANNEL BOARD
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