JVC DX-T99A User manual

SERVICE MANUAL
COPYRIGHT © 2006 Victor Company of Japan, Limited No.MB531
2006/6
COMPACT COMPONENT SYSTEM
MB53120066
DX-T99A,DX-T99EE,DX-T99US,DX-T99UW,
DX-T99UX,DX-T99UG,DX-T99UN,
DX-T77EE,DX-T77US,DX-T77UW,DX-T77UX,
DX-T77UY,DX-T77UG,DX-T77UN,
DX-T66EE,DX-T66US,DX-T66UW,DX-T66UX,
DX-T66UY,DX-T66UG,DX-T66UN
Lead free solder used in the board (material : Sn-Ag-Cu, melting point : 219 Centigrade)
TABLE OF CONTENTS
1 PRECAUTION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-6
2 SPECIFIC SERVICE INSTRUCTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-9
3 DISASSEMBLY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-10
4 ADJUSTMENT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-62
5 TROUBLESHOOTING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-65
SUPER VIDEO
CA-DXT66SP-DXT99W SP-DXT66FSP-DXT66F CA-DXT77SP-DXT77S SP-DXT77SSP-DXT99WSP-DXT99FSP-DXT99F
SP-DXT77C
SUPER VIDEO
CA-DXT99SP-DXT99S SP-DXT99SSP-DXT99WSP-DXT99W SP-DXT99FSP-DXT99F
SP-DXT99C
SUPER VIDEO

1-2 (No.MB531)
SPECIFICATION
DX-T99
Amplifier section Output Power FRONT SPEAKERS 150 W per channel, min. RMS, driven into 4 Ωat 1 kHz with no more
than 10% total harmonic distortion.
CENTER SPEAKER 140 W per channel, min. RMS, driven into 6 Ωat 1 kHz with no more
than 10% total harmonic distortion.
SURROUND SPEAKERS 130 W per channel, min. RMS, driven into 6 Ωat 1 kHz with no more
than 10% total harmonic distortion. (for austraria and russia)
140 W per channel, min. RMS, driven into 6 Ωat 1 kHz with no more
than 10% total harmonic distortion. (for asia)
SUBWOOFERS 150 W per channel, min. RMS, driven into 4 Ωat 63 Hz with no more
than 10% total harmonic distortion. (for austraria and russia)
150 W per channel, min. RMS, driven into 4 Ωat 1 kHz with no more
than 10% total harmonic distortion. (for asia)
Digital output OPTICAL DIGITAL OUTPUT -21 dBm to -15 dBm (660 nm ±30 nm)
Audio input sensitivity/
Impedance*
AUX 300 mV/47 kΩ
MIC 1/2 3.0 mV/50 kΩ
VIDEO OUT Color system NTSC/PAL selectable
VIDEO (composite) 1 V(p-p)/75 Ω
S-VIDEO Y (luminance) 1 V(p-p)/75 Ω
C (chrominance, burst) NTSC : 0.286 V(p-p)/75 Ω
PAL : 0.3 V(p-p)/75 Ω
COMPONENT
(Interlace/Progressive)
(Y) 1 V(p-p)/75 Ω
(PB/PR) 0.7 V(p-p)/75 Ω
Speaker Terminals 4 Ω- 16 Ω(front speakers/subwoofers)
6 Ω- 16 Ω(surround/center speakers)
Tuner section FM tuning range 87.50 MHz - 108.00 MHz
AM (MW) tuning range 531 kHz - 1 710 kHz (for austraria)
531 kHz - 1 710 kHz (at 9 kHz) (for asia)
530 kHz - 1 710 kHz (at 10 kHz) (for asia)
522 kHz - 1 629 kHz (for russia)
Disc player section Playable disc DVD Video/DVD Audio/CD/VCD/SVCD
CD-R/CD-RW (recorded in Audio CD/Video CD/Super Video CD for-
mats and MP3/WMA/JPEG/MPEG-1/MPEG-2/ASF/DivX files)
DVD-R (recorded in DVD Video format)
DVD-RW (recorded in DVD Video format or DVD-VR format)
Dynamic range 80 dB
Horizontal resolution 500 lines
Wow and flutter Immeasurable
Cassette deck section Frequency response Normal (type I) 50 Hz - 14 000 Hz
Wow and flutter 0.15% (WRMS)
General Power requirement AC 110 V / AC 127 V / AC 220 V / AC 230 V - AC 240 V , (adjustable
with the voltage selector), 50 Hz / 60 Hz
Power consumption 335 W (at operation)
29 W (on standby)
Dimensions (W/H/D) (approx.) 185 mm ×460 mm ×361 mm
Mass (approx.) 11.4 kg

(No.MB531)1-3
DX-T77
Amplifier section Output Power FRONT SPEAKERS 150 W per channel, min. RMS, driven into 4 Ωat 1 kHz with no more
than 10% total harmonic distortion.
CENTER SPEAKER 50 W per channel, min. RMS, driven into 6 Ωat 1 kHz with no more
than 10% total harmonic distortion.
SURROUND SPEAKERS 50 W per channel, min. RMS, driven into 6 Ωat 1 kHz with no more
than 10% total harmonic distortion.
SUBWOOFERS 150 W per channel, min. RMS, driven into 4 Ωat 1kHz with no more
than 10% total harmonic distortion. (for asia)
150 W per channel, min. RMS, driven into 4 Ωat 63 Hz with no more
than 10% total harmonic distortion. (for russia)
Digital output OPTICAL DIGITAL OUTPUT -21 dBm to -15 dBm (660 nm ±30 nm)
Audio input sensitivity/
Impedance*
AUX 300 mV/47 kΩ
MIC 1/2 3.0 mV/50 kΩ
VIDEO OUT Color system NTSC/PAL selectable
VIDEO (composite) 1 V(p-p)/75 Ω
S-VIDEO Y (luminance) 1 V(p-p)/75 Ω
C (chrominance, burst) NTSC : 0.286 V(p-p)/75 Ω
PAL : 0.3 V(p-p)/75 Ω
COMPONENT
(Interlace/Progressive)
(Y) 1 V(p-p)/75 Ω
(PB/PR) 0.7 V(p-p)/75 Ω
Speaker Terminals 4 Ω- 16 Ω(front speakers/subwoofers)
6 Ω- 16 Ω(surround/center speakers)
Tuner section FM tuning range 87.50 MHz - 108.00 MHz
AM (MW) tuning range 531 kHz - 1 710 kHz (at 9 kHz) (for asia)
530 kHz - 1 710 kHz (at 10 kHz) (for asia)
522 kHz - 1 629 kHz (for russia)
Disc player section Playable disc DVD Video/DVD Audio/CD/VCD/SVCD
CD-R/CD-RW (recorded in Audio CD/Video CD/Super Video CD for-
mats and MP3/WMA/JPEG/MPEG-1/MPEG-2/ASF/DivX files)
DVD-R (recorded in DVD Video format)
DVD-RW (recorded in DVD Video format or DVD-VR format)
Dynamic range 80 dB
Horizontal resolution 500 lines
Wow and flutter Immeasurable
Cassette deck section Frequency response Normal (type I) 50 Hz - 14 000 Hz
Wow and flutter 0.15% (WRMS)
General Power requirement AC 110 V / AC 127 V / AC 220 V / AC 230 V - AC 240 V , (adjustable
with the voltage selector), 50 Hz / 60 Hz
Power consumption 270 W (at operation)
25 W (on standby)
Dimensions (W/H/D) (approx.) 185 mm ×460 mm ×361 mm
Mass (approx.) 11.4 kg

1-4 (No.MB531)
DX-T66
Amplifier section Output Power FRONT SPEAKERS 150 W per channel, min. RMS, driven into 4 Ωat 1 kHz with no more
than 10% total harmonic distortion.
SUBWOOFERS 150 W per channel, min. RMS, driven into 4 Ωat 1kHz with no more
than 10% total harmonic distortion. (for asia)
150 W per channel, min. RMS, driven into 4 Ωat 63 Hz with no more
than 10% total harmonic distortion. (for russia)
Digital output OPTICAL DIGITAL OUTPUT -21 dBm to -15 dBm (660 nm ±30 nm)
Audio input sensitivity/
Impedance*
AUX 300 mV/47 kΩ
MIC 1/2 3.0 mV/50 kΩ
VIDEO OUT Color system NTSC/PAL selectable
VIDEO (composite) 1 V(p-p)/75 Ω
S-VIDEO Y (luminance) 1 V(p-p)/75 Ω
C (chrominance, burst) NTSC : 0.286 V(p-p)/75 Ω
PAL : 0.3 V(p-p)/75 Ω
COMPONENT
(Interlace/Progressive)
(Y) 1 V(p-p)/75 Ω
(PB/PR) 0.7 V(p-p)/75 Ω
Speaker Terminals 4 Ω- 16 Ω(front speakers/subwoofers)
6 Ω- 16 Ω(surround/center speakers)
Tuner section FM tuning range 87.50 MHz - 108.00 MHz
AM (MW) tuning range 531 kHz - 1 710 kHz (at 9 kHz) (for asia)
530 kHz - 1 710 kHz (at 10 kHz) (for asia)
522 kHz - 1 629 kHz (for russia)
Disc player section Playable disc DVD Video/DVD Audio/CD/VCD/SVCD
CD-R/CD-RW (recorded in Audio CD/Video CD/Super Video CD for-
mats and MP3/WMA/JPEG/MPEG-1/MPEG-2/ASF/DivX files)
DVD-R (recorded in DVD Video format)
DVD-RW (recorded in DVD Video format or DVD-VR format)
Dynamic range 80 dB
Horizontal resolution 500 lines
Wow and flutter Immeasurable
Cassette deck section Frequency response Normal (type I) 50 Hz - 14 000 Hz
Wow and flutter 0.15% (WRMS)
General Power requirement AC 110 V / AC 127 V / AC 220 V / AC 230 V - AC 240 V , (adjustable
with the voltage selector), 50 Hz / 60 Hz
Power consumption 205 W (at operation)
23 W (on standby)
Dimensions (W/H/D) (approx.) 185 mm ×460 mm ×361 mm
Mass (approx.) 10.8 kg

(No.MB531)1-5
Speaker section
* Measured at 1 kHz, with tape recording signal 300 mV
Design and specifications are subject to change without notice.
Main Speakers Type 3-Way 3-Speaker Bass Reflex (Magnetically-Shielded Type)
Speaker systems Woofer 18 cm cone ×1
Mid 6.5 cm cone ×1
Tweeter 2 cm dome ×1
Power handling capacity 150 W
Impedance 4 Ω
Frequency range 35 Hz - 25 000 Hz
Sound pressure level 85 dB/W·m
Dimensions (W/H/D) (approx.) 204 mm ×460 mm ×273 mm
Mass (approx.) 5.2 kg each
Subwoofer Type 1-Way Bass-Reflex (Magnetically-Shielded Type)
Speaker systems 20 cm cone ×1
Power handling capacity 150 W
Impedance 4 Ω
Frequency range 35 Hz - 5 000 Hz
Sound pressure level 88 dB/W·m
Dimensions (W/H/D) (approx.) 238 mm ×460 mm ×273 mm
Mass (approx.) 7.1 kg

1-6 (No.MB531)
SECTION 1
PRECAUTION
1.1 Safety Precautions
(1) This design of this product contains special hardware and
many circuits and components specially for safety purpos-
es. For continued protection, no changes should be made
to the original design unless authorized in writing by the
manufacturer. Replacement parts must be identical to
those used in the original circuits. Services should be per-
formed by qualified personnel only.
(2) Alterations of the design or circuitry of the product should
not be made. Any design alterations of the product should
not be made. Any design alterations or additions will void
the manufacturers warranty and will further relieve the
manufacture of responsibility for personal injury or property
damage resulting therefrom.
(3) Many electrical and mechanical parts in the products have
special safety-related characteristics. These characteris-
tics are often not evident from visual inspection nor can the
protection afforded by them necessarily be obtained by us-
ing replacement components rated for higher voltage, watt-
age, etc. Replacement parts which have these special
safety characteristics are identified in the Parts List of Ser-
vice Manual. Electrical components having such features
are identified by shading on the schematics and by ( ) on
the Parts List in the Service Manual. The use of a substitute
replacement which does not have the same safety charac-
teristics as the recommended replacement parts shown in
the Parts List of Service Manual may create shock, fire, or
other hazards.
(4) The leads in the products are routed and dressed with ties,
clamps, tubings, barriers and the like to be separated from
live parts, high temperature parts, moving parts and/or
sharp edges for the prevention of electric shock and fire
hazard. When service is required, the original lead routing
and dress should be observed, and it should be confirmed
that they have been returned to normal, after reassem-
bling.
(5) Leakage shock hazard testing
After reassembling the product, always perform an isola-
tion check on the exposed metal parts of the product (an-
tenna terminals, knobs, metal cabinet, screw heads,
headphone jack, control shafts, etc.) to be sure the product
is safe to operate without danger of electrical shock.Do not
use a line isolation transformer during this check.
• Plug the AC line cord directly into the AC outlet. Using a
"Leakage Current Tester", measure the leakage current
from each exposed metal parts of the cabinet, particular-
ly any exposed metal part having a return path to the
chassis, to a known good earth ground. Any leakage cur-
rent must not exceed 0.5mA AC (r.m.s.).
• Alternate check method
Plug the AC line cord directly into the AC outlet. Use an
AC voltmeter having, 1,000Ωper volt or more sensitivity
in the following manner. Connect a 1,500Ω10W resistor
paralleled by a 0.15µF AC-type capacitor between an ex-
posed metal part and a known good earth ground.
Measure the AC voltage across the resistor with the AC
voltmeter.
Move the resistor connection to each exposed metal
part, particularly any exposed metal part having a return
path to the chassis, and measure the AC voltage across
the resistor. Now, reverse the plug in the AC outlet and
repeat each measurement. Voltage measured any must
not exceed 0.75 V AC (r.m.s.). This corresponds to 0.5
mA AC (r.m.s.).
1.2 Warning
(1) This equipment has been designed and manufactured to
meet international safety standards.
(2) It is the legal responsibility of the repairer to ensure that
these safety standards are maintained.
(3) Repairs must be made in accordance with the relevant
safety standards.
(4) It is essential that safety critical components are replaced
by approved parts.
(5) If mains voltage selector is provided, check setting for local
voltage.
1.3 Caution
Burrs formed during molding may be left over on some parts
of the chassis.
Therefore, pay attention to such burrs in the case of pre-
forming repair of this system.
1.4 Critical parts for safety
In regard with component parts appearing on the silk-screen
printed side (parts side) of the PWB diagrams, the parts that are
printed over with black such as the resistor ( ), diode ( )
and ICP ( ) or identified by the " " mark nearby are critical
for safety. When replacing them, be sure to use the parts of the
same type and rating as specified by the manufacturer.
(This regulation dose not Except the J and C version)
Good earth ground
Place this
probe on
each exposed
metal part.
AC VOLTMETER
(Having 1000
ohms/volts,
or more sensitivity)
1500 10W
0.15 F AC TYPE

(No.MB531)1-7
1.5 Preventing static electricity
Electrostatic discharge (ESD), which occurs when static electricity stored in the body, fabric, etc. is discharged, can destroy the laser
diode in the traverse unit (optical pickup). Take care to prevent this when performing repairs.
1.5.1 Grounding to prevent damage by static electricity
Static electricity in the work area can destroy the optical pickup (laser diode) in devices such as laser products.
Be careful to use proper grounding in the area where repairs are being performed.
(1) Ground the workbench
Ground the workbench by laying conductive material (such as a conductive sheet) or an iron plate over it before placing the
traverse unit (optical pickup) on it.
(2) Ground yourself
Use an anti-static wrist strap to release any static electricity built up in your body.
(3) Handling the optical pickup
• In order to maintain quality during transport and before installation, both sides of the laser diode on the replacement optical
pickup are shorted. After replacement, return the shorted parts to their original condition.
(Refer to the text.)
• Do not use a tester to check the condition of the laser diode in the optical pickup. The tester's internal power source can easily
destroy the laser diode.
1.6 Handling the traverse unit (optical pickup)
(1) Do not subject the traverse unit (optical pickup) to strong shocks, as it is a sensitive, complex unit.
(2) Cut off the shorted part of the flexible cable using nippers, etc. after replacing the optical pickup. For specific details, refer to the
replacement procedure in the text. Remove the anti-static pin when replacing the traverse unit. Be careful not to take too long a
time when attaching it to the connector.
(3) Handle the flexible cable carefully as it may break when subjected to strong force.
(4) I t is not possible to adjust the semi-fixed resistor that adjusts the laser power. Do not turn it.
1.7 Attention when traverse unit is decomposed
*Please refer to "Disassembly method" in the text for the pickup unit.
• Apply solder to the short land sections before the card wire is disconnected from the connecto on the servo board. (If the card wire
is disconnected without applying solder, the pickup may be destroyed by static electricity.)
• In the assembly, be sure to remove solder from the short land sections after connecting the card wire.
1M
Conductive material
(conductive sheet) or iron palate
(caption)
Anti-static wrist strap
DVD changer mechanism assembly
Switch board
DVD traverse mechanism assembly
DVD servo board

1-8 (No.MB531)
1.8 Important for laser products
1.CLASS 1 LASER PRODUCT
2.CAUTION :
(For U.S.A.) Visible and/or invisible class II laser radiation
when open. Do not stare into beam.
(Others) Visible and/or invisible class 1M laser radiation
when open. Do not view directly with optical instruments.
3.CAUTION : Visible and/or invisible laser radiation when
open and inter lock failed or defeated. Avoid direct
exposure to beam.
4.CAUTION : This laser product uses visible and/or invisible
laser radiation and is equipped with safety switches which
prevent emission of radiation when the drawer is open and
the safety interlocks have failed or are defeated. It is
dangerous to defeat the safety switches.
5.CAUTION : If safety switches malfunction, the laser is able
to function.
6.CAUTION : Use of controls, adjustments or performance of
procedures other than those specified here in may result in
hazardous radiation exposure.
REPRODUCTION AND POSITION OF LABELS and PRINT
!Please use enough caution not to
see the beam directly or touch it
in case of an adjustment or operation
check.
WARNING LABEL and PRINT

(No.MB531)1-9
SECTION 2
SPECIFIC SERVICE INSTRUCTIONS
This service manual does not describe SPECIFIC SERVICE INSTRUCTIONS.

1-10 (No.MB531)
SECTION 3
DISASSEMBLY
3.1 Main body section
3.1.1 Removing the metal cover
(See Fig.1, 2)
(1) From the both sides of the main body, remove the six
screws Aattaching the metal cover. (See Fig.1)
(2) From the back side of the main body, remove the eight
screws Battaching the metal cover. (See Fig.2)
(3) Remove the metal cover from the main body while lifting
the rear section of the metal cover in the direction of the ar-
row. (See Fig.1)
Fig.1
Fig.2
Metal cover
AA
Metal cove
r
B
BB

(No.MB531)1-11
3.1.2 Removing the front panel assembly
(See Fig.3 to 5)
• Remove the metal cover.
(1) From the right side of the main body, disconnect the card
wire from the connectors CN740 on the reverse side of the
main board. (See Fig.3)
(2) From the left side of main body, disconnect the card wires
from the connectors (CN720, CN730) on the forward side
of the main board. (See Fig.4)
(3) Disconnect the parallel wire while releasing the lock of the
connector CN105 on the primary board in the direction of
the arrow. (See Fig.4)
(4) From the both side of the main body, remove the two
screws Cattaching the front panel assembly to the main
body. (See Fig.3, 4)
(5) From the bottom side of the main body, remove the two
screws Dattaching the front panel assembly. (See Fig.5)
(6) From the both side of main body, release the claws aand
remove the front panel assembly from the main body in the
direction of the arrow. (See Fig.3, 4)
Fig.3
Fig.4
Fig.5
Front panel assembly Main board
CN740
a
C
CN730 CN720
Primary board
Front panel assemblyMain board
C
a
CN105
Lock
Front panel assembly
D

1-12 (No.MB531)
3.1.3 Removing the tuner
(See Fig.6)
• Remove the metal cover.
(1) From the back side of the main body, remove the two
screws Eattaching the tuner to the rear panel.
(2) Take out the tuner from the main body and disconnect the
card wire from the connector CN1 on the tuner.
Fig.6
E
Tuner
CN1
Tuner
Rear panel

(No.MB531)1-13
3.1.4 Removing the DVD changer mechanism assembly
(See Fig.7 to 9)
• Remove the metal cover.
(1) From the left side of the main body, disconnect the card
wires from the connectors (CN800, CN810) on the main
board. (See Fig.7) [For DX-T99, DX-T77]
(2) Form the left side of the main body, disconnect the card
wires from the connector on the CN800 on the main board.
(See Fig.7) [For DX-T66]
(3) From the top side of the main body, remove the two screws
Fattaching the DVD changer mechanism assembly on the
mecha chassis. (See Fig.8)
(4) Take out the DVD changer mechanism assembly from the
main body and disconnect the card wire from the connector
CN930 on the video board. (See Fig.8)
Reference:
When the resolution of the DVD changer mechanism assem-
bly is done sequentially, release the claws bof the tray fitting
and remove the five tray fitting from the DVD changer mecha-
nism assembly. (See Fig.9)
Fig.7
Fig.8
Fig.9
CN800 CN810
Main board
DVD changer mechanism assembly
DVD changer mechanism assembly
CN930
Video board
FF
Tray fitting bb
DVD changer mechanism assembly

1-14 (No.MB531)
3.1.5 Removing the DVD changer mechanism assembly
(See Fig.10, 11)
• Remove the metal cover and DVD changer mechanism as-
sembly.
(1) From the back side of the metal body, remove the three
screws Gattaching the video board to the rear panel. (See
Fig.10)
(2) From the top side of the main body, disconnect the card
wires from the connectors (CN920, CN931) on the video
board. (See Fig.11)
(3) Take out the video board in the direction of the arrow while
removing it from the sections cof the mecha chassis. (See
Fig.11)
Fig.10
Fig.11
Video board
Rear panel
G
Mecha chassis
CN920 CN931
cc
Video board

(No.MB531)1-15
3.1.6 Removing the fan
(See Fig.12, 13)
• Remove the metal cover.
(1) From the back side of the main body, remove the screw H
attaching the rear cover to the rear panel. (See Fig.12)
(2) Remove the joints dand remove the rear cover. (See
Fig.12) From the left side of the main body, disconnect the
wire from the connector CN304 on the amplifier 2 board.
(See Fig.13) [DX-T99]
(3) Remove the joints dand remove the rear cover. (See
Fig.12) From the left side of the main body, disconnect the
wire from the connector CN604 on the amplifier 2 board.
(See Fig.13) [For DX-T66, DX-T77]
(4) Release the two joints eof the fan bracket in the direction
of the arrow and take out the fan with the fan bracket. (See
Fig.13)
Reference:
Remove the fan from the fan bracket as required.
Fig.12
Fig.13
Rear panel Rear cove
r
dd
d
dd
d
d
H
Fan
Fan bracket
e
CN304
(CN604)
Amplifier 2
board

1-16 (No.MB531)
3.1.7 Removing the rear panel
(See Fig.14)
• Remove the metal cover and fan.
(1) Remove the two screws Jand eleven screws Kattaching
the rear panel. [For DX-T99, DX-T77]
(2) Remove the two screws Jand ten screws Kattaching the
rear panel. [For DX-T66]
(3) Release the section fof the rear panel and remove the
joints gof the mecha chassis in the direction of the arrow.
(4) Remove the rear panel from the main body.
Fig.14
Mecha chassis
Rear panel
g
f
f
g
K
K
K
K
J
[DX-T99, DX-T77]
[DX-T66]
Mecha chassis
Rear panel
g
ff
g
K
K
K
K
J
K
K

(No.MB531)1-17
3.1.8 Removing the main board
(See Fig.15)
• Remove the metal cover, tuner, fan and rear panel.
(1) From the right side of the main body, remove the screw L
and screw Mattaching the main board.
(2) From the inside of the main body, disconnect the card wires
from the connectors (CN820, CN830) on the forward side
of the main board.
(3) Disconnect the main board from the bridge board toward
this side while releasing the claw hof the connector CN850
on the main board.
(4) Disconnect the main board from the surround terminal
board in the direction of the arrow while releasing the claw
Iof the connector CN860 on the surround terminal board.
[For DX-T99, DX-T77]
Note:
When releasing the claws (h, j) take care not to break them.
Fig.15
CN820
CN830
Main board
M
L
Main board
j
Main board
Bridge board
CN850
h
Surround
terminal board
CN860

1-18 (No.MB531)
3.1.9 Removing the amplifier 1 and amplifier 2 boards
(See Fig.16 to 18) [For DX-T99]
• Remove the metal cover, tuner, fan, rear panel and main
board.
(1) From the right side of the main body, remove the screw N
attaching the earth wires to the bottom chassis. (See
Fig.16)
Reference:
After reassembling, fix the earth wires with the spacer as
before. (See Fig.16)
(2) Disconnect the amplifier 2 board from the bridge board in
the direction of the arrow while releasing the claw kof the
connector CN200 on the bridge board. (See Fig.16)
(3) Disconnect the amplifier 1 board from the bridge board in
the direction of the arrow while releasing the claw kof the
connector CN201 on the bridge board. (See Fig.17)
Note:
When releasing the claws (k, l), take care not to break
them. (See Fig.17, 18)
(4) Take out the amplifier 1 board and amplifier 2 board togeth-
er from the main body.
(5) Remove the two screws Pand remove the leaf spring. (See
Fig.18)
(6) Remove the two screws Pand remove the amplifier 1
board from the heat sink. (See Fig.18)
(7) Remove the four screws Pand remove the amplifier 2
board from the heat sink. (See Fig.18)
3.1.10 Removing the amplifier 1 and amplifier 2 boards
(See Fig.16 to 18) [For DX-T77, DX-T66]
• Remove the metal cover, tuner, fan, rear panel and main
board.
(1) From the right side of the main body, remove the crew N
attaching the earth wires to the bottom chassis. (See
Fig.16)
Reference:
After reassembling, fix the earth wires with the spacer as
before. (See Fig.16)
(2) Disconnect the amplifier 2 board from the bridge board in
the direction of the arrow while releasing the claw kof the
connector CN200 on the bridge board. (See Fig.16)
(3) Disconnect the amplifier 1 board from the bridge board in
the direction of the arrow while releasing the claw lof the
connector CN201 on the bridge board. (See Fig.17)
Note:
When releasing the claws (k, l), take care not to break
them. (See Fig.16, 17)
(4) Take out the amplifier 1 board and amplifier 2 board togeth-
er from the main board.
(5) Remove the two screws Pand remove the leaf spring. (See
Fig.18)
(6) Remove the two screws Pand remove the amplifier 1
board from the heat sink. (See Fig. 18) [For DX-T77]
(7) Remove the three screws Pand remove the amplifier 2
board from the heat sink. (See Fig.18)
Fig.16
Fig.17
Bridge board Amplifier 2 board
NBottom chassis
Earth wires
Spacer CN200
k
Bridge board
Amplifier 1 board
Bridge board
CN201
Bridge board
l

(No.MB531)1-19
Fig.18
P
P
P
P
P
P
Amplifier 1 board Amplifier 2 board
Leaf spring Heat sink
P
P
[DX-T77]
Amplifier 1 board Amplifier 2 board
Leaf spring Heat sink
P
P
[DX-T99]
Amplifier 1 board Amplifier 2 board
Leaf spring Heat sink
P
[DX-T66]

1-20 (No.MB531)
3.1.11 Removing the primary board
(See Fig.19)
• Remove the metal cover, tuner, fan ,rear panel, main board,
amplifier 1 board and amplifier 2 board.
(1) From the left side of the main body, remove the screw Qat-
taching the primary board.
(2) Disconnect the wires from the connectors (CN103, CN106)
on the primary board.
(3) Release the claw mof the connector CN104 on the primary
board.
Note:
When releasing the claw m, take care not to break it.
(4) Disconnect the wires from connectors (CN101, CN102) on
the forward side of the primary board.
(5) Disconnect the power cord from the connector CN100 on
the primary board.
(6) Take out the primary board from the main body.
Fig.19
3.1.12 Removing the primary board
(See Fig.20)
• Remove the metal cover, tuner, fan, rear panel, main board,
amplifier 1 board, amplifier 2 board and primary board.
(1) Remove the wire holders bundling the wires.
References:
After reassembling, bundle the wires with the wire hold-
ers as before.
(2) Remove the screw Rattaching the bridge board.
(3) Take out the bridge board from the main body.
Fig.20
CN103
CN106
CN102
CN104
CN101
CN100
Primary board
Power cord
Q
Primary board
Bridge board
m
Wire holders
Bridge board R