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DV-P250 is a device for DVD playback.
This device is to be used by connecting it to the
video input terminal of a TV set.
6
Disc navigation system facilitates program
search.
6
Speedy operation by 2x speed drive.
ADVICE
Please carefully read this guide before using the device. The Hitachi DVD Player has been designed to
prevent fire, electrical shock, injury, or harmful radiation. It has been legally fabricated in accordance with
the Electrical Appliances Act. Therefore, when using the device, please follow advice in this service
guide to keep it safe to use.
1. In brief
2. Features
SPECIFICATIONS AND PARTS ARE SUBJECT TO CHANGE FOR IMPROVEMENT.
July 1999
Digital Media Products Division, Tokai
SERVICE MANUAL
DV-P250U/(PX)
DV-P250E/(UK)
DV-P250A/(M)/(S)/(AU)
DV-P250C
TK
NO. 9901E
DVD PLAYER


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II
Before undertaking repair work, please read through this [Precautions for safety].
The following points should be observed in order to prevent accidents from happening and to ensure the
safety of the device.
Degrees of danger or damage that can be caused by faulty operation are indicated by the following marks:
The following marks identify actions to be taken:
PRECAUTIONS FOR SAFETY(Please follow.)
Under this mark, there is "Possible death or serious injury".
Under this mark, there is "Possible injury or material damage".
This mark indicates items to which `You
should pay attention'.
This mark indicates items `You have to
accomplish'.
This mark indicates: `You should be cau-
tious of electric shock'.
This mark indicates `Forbidden items'.
You should pay attention.
The original part installation and wiring route
shall be restored.
Where a special attention is required, it is
indicated by a label or stamp. For example, on
the cabinet, chassis, or parts.
Please respect the indicated items and the
`Precautions for use' of the manual.
For safety, some parts are insulated by a tube
or a tape, or installed without contact with
substrate. The internal wiring is kept a
distance from hot or high voltage parts by
clamps or routing. Please restore them as
initially done to prevent electric shock or fire
from happening.
You should be cautious against electric shock.
Please be careful during operations because
there are high voltage and recharging parts
inside. An electric shock or death may happen
by touching them.
When disassembling, assembling, or replacing
a part, the power plug has to be pulled off.
Touching by error a powered part may cause
an electric shock, death, or injury.
Please check safety after servicing.
Please check if dismounted screws, parts, and
wires are reinstalled as before and if the area
surrounding the repair is damaged.
Please also measure insulation resistance with
a ohmmeter and to confirm that it is more than
20M
.
There is risk of electric shock or fire if the
insulation resistance is less than 20M
.
Please use designated parts.
Parts are characterized by uninflammability
and voltage resistance. Therefore, parts
having these same characteristics must be
used in replacement.
Especially for parts important in insuring
safety, identified by
in the schematic or
parts list, a part with the identical part number
shall be used.
If a part with a different part number is used,
an electric shock or a fire may occur.
WARNING
CAUTION
WARNING


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III
Chapter 1
System Introduction
System Specification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1
Hitachi DV-P250E . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1
Hitachi DV-P250U/DV-P250A/DV-P250C . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2
ACER DVD-5500/DVD-5300 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3
ACER DVD-5100 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4
System Outlook . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
Front Panel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
Rear Panel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6
Description of adopted new technology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
Digital signal circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
Video circuit (DEC substrate). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
VIDEO OUTPUT CIRCUIT (RJK substrate) . . . . . . . . . . . . . . . . . . . . . . . . . . . .13
AUDIO CIRCUIT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13
KARAOKE CIRCUIT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16
FRONT (FSW) SUBSTRATE CIRCUIT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18
POWER SUPPLY CIRCUIT. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18
CLOCK CIRCUITS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19
Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22
VIDEO CIRCUIT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22
AUDIO CIRCUIT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23
KARAOKE CIRCUIT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24
About System Reset Function . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .25
System Utility . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .25
Chapter 2
Removal and Replacement
Prelimaries before disassembling machines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .27
Before You Begin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .27
Disassembly Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .29
Removing the Top Cover . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .29
Removing the FootStand . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .29
Removing the Front Panel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .30
Removing the MPEG Control Board . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .31
Removing the Power Supply Board . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .32
Removing the DVD-ROM Drive . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .32
Removing the Outlet Board . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .33
Removing the Front Panel Control Boards . . . . . . . . . . . . . . . . . . . . . . . . . . . . .34
Connector Setting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .36
Appendix A
Schematics
DEC Board (A side) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .37
DEC Board (B side) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .38
RJK Board (A side) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .39
RJK Board (B side) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .40
FSW/MVR/FJK Board (A side) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .41
FSW/MVR/FJK Board (B side) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .42
System Block Diagrams. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .43
Exploded Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .44
Replacement Parts List (DV-P250) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .45
Table Of Contents


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Chapter 1
1
System Specification
Hitachi DV-P250E
Specification
General
Model .................................................................................................................... DV-P250E
Operating laser ......... Semi-conductor laser : Wave length 650nm(DVD) / 780nm(CD,VCD)
Power supply ................................................................................................. AC230V, 50Hz
Power consumption ........................................................................................................27W
Weight ......................................................................................................................... .3.9 Kg
Overall size ...........................................................................434 (W) x 315 (D) x 98 (H) mm
Allowable operating temperature ..................................................................... +5°C~+35°C
Allowable operating humidity ...................................................... 15~75% (no condensation)
AV connector output
terminal
AV connector output.................................................................................... 21-pin connector
This connector provides the video and signals for connection to a color video TV monitor (or
TV set) which has an `AV CONNECTOR' terminal.
S Video output terminal
Y output level .......................................................................................... ........... 1Vp-p (75
)
C output level ................................................................................. NTSC : 0.286Vp-p (75
)
...............................................................................................................PAL : 0.3Vp-p (75
)
Output terminal ......................................................................................................S terminal
Video output
Output level ........................................................ 1 Vp-p (synchronous when loaded at 75
)
Output terminal ..........................................................................................................pin jack
Audio output
Output level .................................................................................... 200mVrms (1KHz, -20dB)
Analog audio output ........................................................................... 2 system (pin jack x 4)
Sound characteristics :
Frequency characteristics ............................................................CD : 4Hz~20KHz (EIAJ)
.................................................................................... DVD : 4Hz~22KHz (48K sampling)
...............................................................................................4Hz~44KHz (96K sampling)
SN ratio ...................................................................................................................110 dB
Dynamic range .........................................................................................................100dB
Total harmonic distortion rate .................................................................................0.003%
Wow fluttertics .............................Measurement limit less than (±0.001% W.PEAK)(EIAJ)
Other terminals
Digital audio output optical/coaxial.......................................................... Coaxial terminal : 1
(DTS/AC-3/MPEG2, AC3, LPCM, OFF commutable) ....................... Optical connector : 1
Accessories
Remote control unit .............................................................................................................. 1
Single `AAA' battery.............................................................................................................. 2
AV cord................................................................................................................................. 1
Power cord ........................................................................................................................... 1
System Introduction
Chapter 1