Text preview for : hfe_toshiba_d-r250s_255s_service_en.pdf part of TOSHIBA hfe toshiba d-r250s 255s service en TOSHIBA DVD D-R250S hfe_toshiba_d-r250s_255s_service_en.pdf



Back to : hfe_toshiba_d-r250s_255s_ | Home

FILE NO. 810-200559




SERVICE MANUAL




DVD RECORDER

D-R250SB
D-R255SF
D-R255SG



JUL. 2005 S
CONTENTS

1. Precautions
2. Product Specification
3. Software Update
4. Disassembly and Reassembly
5. Troubleshooting
6. Exploded View and Parts List
7. Electrical Parts List
8. Block Diagram
9. Wiring Diagram
10. PCB Diagrams
11. Schematic Diagrams
12. Operating Instructions
13. Circuit Operating Descriptions
14. Reference Information
MEMO
1. Precautions
1-1 Safety Precautions

1) Before returning an instrument to the customer, Any measurements not within the limits specified
always make a safety check of the entire instrument, herein indicate a potential shock hazard that must
including, but not limited to, the following items: be eliminated before returning the instrument to
the customer.
(1) Be sure that no built-in protective devices are
defective or have been defeated during servicing.
(READING SHOULD
(1)Protective shields are provided to protect both NOT BE ABOVE
the technician and the customer. Correctly replace 0.5mA)
LEAKAGE
all missing protective shields, including any DEVICE CURRENT
UNDER TESTER
removed for servicing convenience. TEST
(2)When reinstalling the chassis and/or other as- TEST ALL
sembly in the cabinet, be sure to put back in place EXPOSED METER
SURFACES
all protective devices, including, but not limited to,
nonmetallic control knobs, insulating fish papers, 2-WIRE CORD

adjustment and compartment covers/shields, and ALSO TEST WITH EARTH
isolation resistor/capacitor networks. Do not oper- PLUG REVERSED GROUND
(USING AC ADAPTER
ate this instrument or permit it to be operated with- PLUG AS REQUIRED)
out all protective devices correctly installed and
functioning. Fig. 1-1 AC Leakage Test

(2) Be sure that there are no cabinet openings through (4) Insulation Resistance Test Cold Check-(1) Unplug
which adults or children might be able to insert the power supply cord and connect a jumper wire
their fingers and contact a hazardous voltage. Such between the two prongs of the plug. (2) Turn on the
openings include, but are not limited to, excessive- power switch of the instrument. (3) Measure the
ly wide cabinet ventilation slots, and an improper- resistance with an ohmmeter between the
ly fitted and/or incorrectly secured cabinet back jumpered AC plug and all exposed metallic cabinet
cover. parts on the instrument, such as screwheads,
antenna, control shafts, handle brackets, etc. When
(3) Leakage Current Hot Check-With the instrument an exposed metallic part has a return path to the
completely reassembled, plug the AC line cord chassis, the reading should be between 1 and 5.2
directly into a 230V(220V ~ 240V) AC outlet. (Do megohm. When there is no return path to the chas-
not use an isolation transformer during this test.) sis, the reading must be infinite. If the reading is
Use a leakage current tester or a metering system not within the limits specified, there is the possibil-
that complies with American National Standards ity of a shock hazard, and the instrument must be
institute (ANSI) C101.1 Leakage Current for repaired and rechecked before it is returned to the
Appliances and Underwriters Laboratories (UL) customer. See Fig. 1-2.
1270 (40.7). With the instrument's AC switch first in
the ON position and then in the OFF position, mea-
Antenna
sure from a known earth ground (metal water pipe, Terminal
conduit, etc.) to all exposed metal parts of the
instrument (antennas, handle brackets, metal cabi-
nets, screwheads, metallic overlays, control shafts,
Exposed
etc.), especially any exposed metal parts that offer Metal Part
an electrical return path to the chassis.
Any current measured must not exceed 0.5mA.
Reverse the instrument power cord plug in the out- ohm
ohmmeter
let and repeat the test. See Fig. 1-1.
Fig. 1-2 Insulation Resistance Test


1-1
Precautions


2) Read and comply with all caution and safety re- 5) Components, parts, and/or wiring that appear to
lated notes on or inside the cabinet, or on the chas- have overheated or that are otherwise damaged
sis. should be replaced with components, parts and/ or
wiring that meet original specifications.
3) Design Alteration Warning-Do not alter or add to Additionally, determine the cause of overheating
the mechanical or electrical design of this instru- and/or damage and, if necessary, take corrective
ment. Design alterations and additions, including action to remove any potential safety hazard.
but not limited to, circuit modifications and the
addition of items such as auxiliary audio output 6) Product Safety Notice-Some electrical and mechani-
connections, might alter the safety characteristics of cal parts have special safety-related characteristics
this instrument and create a hazard to the user. Any which are often not evident from visual inspection,
design alterations or additions will make you, the nor can the protection they give necessarily be
servicer, responsible for personal injury or property obtained by replacing them with components rated
damage resulting therefrom. for higher voltage, wattage, etc. Parts that have spe-
cial safety characteristics are identified by shading,
4) Observe original lead dress. Take extra care to an ( )or a ( )on schematics and parts lists. Use
assure correct lead dress in the following areas: of a substitute replacement that does not have the
(1) near sharp edges, (2) near thermally hot parts (be same safety characteristics as the recommended
sure that leads and components do not touch ther- replacement part might create shock, fire and/or
mally hot parts), (3) the AC supply, (4) high voltage, other hazards. Product safety is under review con-
and (5) antenna wiring. Always inspect in all areas tinuously and new instructions are issued whenev-
for pinched, out-of-place, or frayed wiring, Do not er appropriate.
change spacing between a component and the
printed-circuit board. Check the AC power cord for
damage.




1-2
Precautions


1-2 Servicing Precautions
CAUTION : Before servicing units covered by this
service manual and its supplements, read and follow
the Safety Precautions section of this manual.
(4) An insulation tube or tape is sometimes used and
some components are raised above the printed
Note : If unforseen circumstances create conflict
wiring board for safety. The internal wiring is
between the following servicing precautions and any
sometimes clamped to prevent contact with heat-
of the safety precautions, always follow the safety pre-
ing components. Install such elements as they
cautions. Remember: Safety First.
were.

1-2-1 General Servicing Precautions (5) After servicing, always check that the removed
screws, components, and wiring have been in-
(1) a. Always unplug the instrument's AC power cord stalled correctly and that the portion around the
from the AC power source before (1) re-moving serviced part has not been damaged and so on.
or reinstalling any component, circuit board, Further, check the insulation between the blades of
module or any other instrument assembly, (2) the attachment plug and accessible conductive
disconnecting any instrument electrical plug or parts.
other electrical connection, (3) connecting a test
substitute in parallel with an electrolytic capaci-
tor in the instrument.
1-2-2 Insulation Checking Procedure
b. Do not defeat any plug/socket B+ voltage inter-
Disconnect the attachment plug from the AC outlet
locks with which instruments covered by this
and turn the power ON. Connect the insulation resi-
service manual might be equipped.
stance meter (500V) to the blades of the attachment
c. Do not apply AC power to this instrument and
plug. The insulation resistance between each blade of
/or any of its electrical assemblies unless all
the attachment plug and accessible conductive
solid-state device heat sinks are correctly in-
parts(see note) should be more than 1 Megohm.
stalled.
d. Always connect a test instrument's ground lead
Note : Accessible conductive parts include metal pan-
to the instrument chassis ground before connect-
els, input terminals, earphone jacks, etc.
ing the test instrument positive lead. Always
remove the test instrument ground lead last.

Note : Refer to the Safety Precautions section ground
lead last.

(2) The service precautions are indicated or printed on
the cabinet, chassis or components. When servic-
ing, follow the printed or indicated service precau-
tions and service materials.

(3) The components used in the unit have a specified
flame resistance and dielectric strength.
When replacing components, use components
which have the same ratings. Components identi-
fied by shading, by( ) or by ( ) in the circuit dia-
gram are important for safety or for the characteris-
tics of the unit. Always replace them with the exact
replacement components.




1-3
Precautions


1-3 ESD Precautions
Electrostatically Sensitive Devices (ESD) (7) Immediately before removing the protective ma-
terials from the leads of a replacement ESD device,
Some semiconductor (solid state) devices can be dam- touch the protective material to the chassis or cir-
aged easily by static electricity. cuit assembly into which the device will be
Such components commonly are called Electrostati- installed.
cally Sensitive Devices(ESD). Examples of typical ESD
devices are integrated circuits and some field-effect CAUTION : Be sure no power is applied to the ch-
transistors and semiconductor chip components. The assis or circuit, and observe all other safety precau-
following techniques should be used to help reduce tions.
the incidence of component damage caused by static
electricity. (8) Minimize bodily motions when handling unpack-
aged replacement ESD devices. (Otherwise harm-
(1) Immediately before handling any semiconductor less motion such as the brushing together of your
component or semiconductor-equipped assembly, clothes fabric or the lifting of your foot from a car-
drain off any electrostatic charge on your body by peted floor can generate static electricity sufficient
touching a known earth ground. Alternatively, to damage an ESD device).
obtain and wear a commercially available dis-
charging wrist strap device, which should be
removed for potential shock reasons prior to apply-
ing power to the unit under test.

(2) After removing an electrical assembly equipped
with ESD devices, place the assembly on a conduc-
tive surface such as aluminum foil, to prevent elec-
trostatic charge buildup or exposure of the assem-
bly.

(3) Use only a grounded-tip soldering iron to solder or
unsolder ESD devices.

(4) Use only an anti-static solder removal devices.
Some solder removal devices not classified as
"anti-static" can generate electrical charges suffi-
cient to damage ESD devices.

(5) Do not use freon-propelled chemicals. These can
generate electrical charges sufficient to damage
ESD devices.

(6) Do not remove a replacement ESD device from its
protective package until immediately before your
are ready to install it.(Most replacement ESD
devices are packaged with leads electrically short-
ed together by conductive foam, aluminum foil or
comparable conductive materials).




1-4
2. Product Specification
2-1 Product Specification

Power requirements 230V AC,50Hz
Power consumption 35Watts
Weight 3.7 Kg
General
Dimensions 430mm(W) x 272mm(D) x 58mm(H)
Operating temp +5