TCL DVD-F61 Schematic
SERVICE MANUAL
DVD-F70
DVD-F61
Table of Contents
Table of Contents .................................................................................................................... 1
Figure 1. Schematic Diagram .............................................................................................................. 2
Figure 2. Basic Circuit Diagram ........................................................................................................... 3
Failure & Troubleshooting of Power Supply .......................................................................................... 4
Troubleshooting and service of the Loader ........................................................................................... 4-5
Troubleshooting and service of Decoding Part ...................................................................................... 5
Troubleshooting and service of Video Part ............................................................................................6
Troubleshooting and service of Audio Part ............................................................................................6
Troubleshooting and service of KARAOKE Part .................................................................................... 6
Full screen display or no display on VFD .............................................................................................. 7
No operation or some keys on the front board, disordered display on VFD ............................................ 7
No sensitive remote reception, or no reception from the remote handset ............................................... 7
The machine can not be turned on or off ............................................................................................... 7
Servo schematic circuit 1 .................................................................................................................... 8
Servo schematic circuit 2 .................................................................................................................... 9
Decoder schematic circuit 1 ................................................................................................................ 10
Decoder schematic circuit 2 ................................................................................................................ 11
Front control board schematic circuit ................................................................................................... 12
Karaoke schematic circuit .................................................................................................................... 13
Output schematic circuit ...................................................................................................................... 14
Power schematic circuit....................................................................................................................... 15
1
MUTE
GND/VSDA0
GND
JP1
POWER
BOARD
+5VP
GND
FRONT
BOARD
MAINL
M/L
Y/G
5V
M/L
1
CN1
CON301
CN4
SL+
1
GND
5V
5V
VS
5
VA-
12
4
Cr/R
PCON
VSTB
VA+
AG
MICD/HR
-24V
CON101
ASPDIF
6
M/R
TRIN
AC1
ABVO ARD
VSCK
CN2
JP1
1
AC2
9
15
VCC
SL-
GND
-24V
GND
VSDA
D L OV DA D
L S
2
AC1
VCC
M/R
CN4
CVBS
AG
Cb/ B
GND
VA+
PCON
SP+
MIC/HL
SUB
KARAOKE
BOARD
3
3.3V
CN8
SP -1
Sc
GND
IR
20
TD-F61/F70/F71
6
CN6
3
TROUT
MAINL
1
Sy
VA-
2
TD-F62/63/F50
VCC
AC2
1 4 8
VA-
GN D
5
CN5
KARAOKE
BOARD
LOAD+
CENT
VA+
GND
RS
6
7
MAINBOARD
HS
Figure 1 Schematic Diagram(TD-F61/F62/F63/F70)
AV BOARD
MAIN BOARD
DVD LOAD
Figure 2 Basic Circuit Diagram
FLASH
EEPROM
AUDIOAMP&LPF
VIDEOD/A
CS4954/4955
PT6312(TD-F50/F61/F62/F63)/PT6554(TD-F70/F71)
WM8746
2402
SDRAM
REMOTEHANDSET
MT1369
VFD/KEY
1M*8
PT2222-001
VIDEOLPF&
DRIVE
SPDIFOUT
TOP233Y(TD-F50/F61/F62/F63)TEA1523P(TD-F70/F71)
RF
POWERSUPPLY
2*16Mbit
PT2399ECHO
MC4558
DECODER&SERVO
D L OV AD D
M C 4 5 5 8M I CA M P
A U D I OD / A
MT1336
DVD LOAD
WM8746
AUDIO D/A
VIDEO D/A
CS4954/4955
POWER SUPPLYREMOTE HANDSET
VIDEO LPF
& DRIVE
SPDIF OUT
MC4558
AUDIO AMP&LPF
Pt2399 ECHO
MC4558 MIC AMP
a. Principle of power supply operating
Adopts switched-mode power supply module TOP233Y of TOPSWITCH company, it can protect
itself from over current, overheating, and short-circuit, etc. This circuitry mainly stabilizes at +5V,
and fluctuates within a permissible range, such as +5V, VA+, VA-, +3.3V and -24V. Please pay
attention to the high voltage inside the white paint of PCB while repairing. When using an oscillator
to measure this portion, an isolated transformer must be connected.
Circuit of power supply may output the following power sources:
Rated Voltage
VCC
+ 5V
+ 3.3V
VA+
VA-
-24V
AC1-AC2
Permissible Range Working Current Working Load
+ 4.75V ~ 5.45V
4.75V ~ 5.45V
3.20V ~ 3.46V
+8V +/-10%
-8V +/-10%
-20V ~ -25V
AC 2.8V ~ AC 3.5V
17mA Front board and muting circuit
520mA
650mA
15mA
15mA
10mA
80mA
Loader servo, motor driver, laser circuit,
audio D/A and T F circuit
Decoder board
Audio & Karaoke circuit
Audio & Karaoke circuit
Bias voltage of VFD on front board
Filament of VFD on front board
b. Troubleshooting and service
a). If +5V voltage varies out of the permissible range, check whether sampling resistance R8 and
R9 (R422 and R423) are eroded, and whether the 1st pin of regulated voltage reference U3 (U402)
TL431 is at 2.5V. If the deviation is over 0.1V, TL431 is eroded and shall be replaced. During
maintenance, the +5V sampling circuit, i.e. D9, R5, R8, R9 and U4 (D415, R419, R422, R423, R421
and U403), shall not be open, otherwise, it may result in high voltage and damage other circuits on
the rear pole.
b). If all the output voltage is 0V, and a voltage of 300V or so exists at the positive pole of C8 (C403),
check whether +5V, +8V, -8V, -24V and +3.3V are short (whether Q401, Q402 and Q403 are open).
c). If +3.3V of AC1-AC2 is 0V and no display on VFD, check whether D6 (D408) is open. If the ribb
on wire is not in good contact, replace the corresponding ribbon wire.
Note: Components in the brackets are of TDE-F70/F71.
2. Troubleshooting and Service of the Loader
pole of Q1 and Q2, and whether U2 and adjacent parts are damaged or weld falsely.
d). If the above parts are normal and no laser emits, replace the loader.
b. Read no disc
a). Check whether the ribbon wire from 24P to loader is in good contact.
b). Check whether the RFO signal of the 10th pin of CN6 is transmitted to the 96th pin of U1.
c). Check whether laser voltage (about 2V for VCD and 2.2V for DVD respectively) exists at the C
pole of Q1 and Q2, and whether the voltage is normal.
d) Check whether U1, U2 and adjacent parts are damaged or weld falsely.
e). If the above parts are normal, replace U1 or the loader.
c. Read DVD discs only or read other discs beyond DVD only
a). Check whether the ribbon wire from 24P to loader is in good contact.
b). Check whether laser voltage of 2V outputs at the C pole of Q2, and whether the 125th pin of U1
is at low level.
c). Check whether the pins from the 1st to the 38th of U1 and adjacent parts are weld falsely,
damaged or erode.
d). If the above parts are normal, replace U1 or the loader.
3. Troubleshooting and service of decoding part
a. No video, no audio, no display on VFD, and no operation of keys
a). Check whether the power sources of the decoder board are normal.
b). Check whether there is 27MHz signal output. If not, X1 crystal and adjacent parts are eroded or
damaged.
c). Check whether there is 81MHz signal output at R64. If not, check whether there is short circuit,
false welding or alien substance for audio D/A circuit U5 and SDRAM U8 and U9.
d). Check whether the reset circuit composed of C7, R37 and D1 is normal (constant 0V after tens
of milliseconds of high level). If it is at low level constantly, C7, R37 and D1 are damaged.
e). If the reset level is normal, check whether the chip selection signal, address and data of the 12th
pin of U5 are normal.
f). Check U10 that whether the data of pins from the 1st to the 8th, hsync and vsync signal of the
10th and 11th pins, and 27MHz signal of the 29th pin are normal, and whether C162 and R68 are
normal. If not, replace U10.
g). When U5 works normally, check the connection between U8, U9 and U3. If abnormal, replace U8
or U9.
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