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PRODUCT SAFETY SERVICING GUIDELINES FOR VIDEO PRODUCTS
CAUTION : DO NOT ATTEMPT TO MODIFY THIS PRODUCT IN ANY WAY, SUBJECT : X-RADIATION
NEVER PERFORM CUSTOMIZED INSTALLATIONS WITHOUT MANUFAC- 1. BE SURE PROCEDURES AND INSTRUCTIONS TO ALL SERVICE PER-
TURER'S APPROVAL. UNAUTHORIZED MODIFICATIONS WILL NOT ONLY SONNEL COVER THE SUBJECT OF X-RADIATION. THE ONLY POTEN-
VOID THE WARRANTY, BUT MAY LEAD TO YOUR BEING LIABLE FOR ANY TIAL SOURCE OF X-RAYS IN CURRENT T.V. RECEIVERS IS THE PIC-
RESULTING PROPERTY DAMAGE OR USER INJURY. TURE TUBE. HOWEVER, THIS TUBE DOES NOT EMIT X-RAYS WHEN
SERVICE WORK SHOULD BE PERFORMED ONLY AFTER YOU ARE THE HIGH VOLTAGE IS AT THE FACTORY SPECIFIED LEVEL. THE
THOROUGHLY FAMILIAR WITH ALL OF THE FOLLOWING SAFETY PROPER VALUE IS GIVEN IN THE APPLICABLE SCHEMATIC. OPERA-
CHECKS AND SERVICING GUIDELINES. TO DO OTHERWISE, TION AT HIGHER VOLTAGES MAY CAUSE A FAILURE OF THE PIC-
INCREASES THE RISK OF POTENTIAL HAZARDS AND INJURY TO THE TURE TUBE OR HIGH VOLTAGE SUPPLY AND, UNDER CERTAIN CIR-
USER. CUMSTANCES, MAY PRODUCE RADIATION IN EXCESS OF DESIR-
WHILE SERVICING, USE AN ISOLATION TRANSFORMER FOR PROTEC- ABLE LEVELS.
TION FROM A.C. LINE SHOCK. 2. ONLY FACTORY SPECIFIED C.R.T. ANODE CONNECTORS MUST BE
USED. DEGAUSSING SHIELDS ALSO SERVE AS X-RAY SHIELD IN
SAFETY CHECKS COLOR SETS, ALWAYS RE-INSTALL THEM.
AFTER THE ORIGINAL SERVICE PROBLEM HAS BEEN CORRCTED. A 3. IT IS ESSNTIAL THAT SERVICE PERSONNEL HAVE AVAILABLE AN
CHECK SHOULD BE MADE OF THE FOLLOWING. ACCURATE AND RELIABLE HIGH VOLTAGE METER. THE CALIBRA
SUBJECT : FIRE & SHOCK HAZARD TION OF THE METER SHOULD BE CHECKED PERIODICALLY
1. BE SURE THAT ALL COMPONENTS ARE POSITIONED IN SUCH A WAY AGAINST A REFERENCE STANDARD, SUCH AS THE ONE AVAILABLE
AS TO AVOID POSSIBILITY OF ADJACENT COMPONENT SHORTS. AT YOUR DISTRIBUTOR.
THIS IS ESPECIALLY IMPORTANT ON THOSE MODULES WHICH ARE 4. WHEN THE HIGH VOLTAGE CIRCUITRY IS OPERATING PROPERLY
TRANSPORTED TO AND FROM THE REPAIR SHOP. THERE IS NO POSSIBILITY OF AN X-RADIATION PROBLEM. EVERY
2. NEVER RELEASE A REPAIR UNLESS ALL PROTECTIVE DEVICES TIME A COLOR CHASSIS IS SERVICED. THE BRIGHTNESS SHOULD
SUCH AS INSULATORS, BARRIERS, COVERS, SHIELDS, STRAIN BE RUN UP AND DOWN WHILE MONITORING THE HIGH VOLTAGE
RELIEFS, POWER SUPPLY CORDS, AND OTHER HARDWARE HAVE WITH A METER TO BE CERTAIN THAT THE HIGH VOLTAGE DOES
BEEN REINSTALLED PER ORIGINAL DESIGN. BE SURE THAT THE NOT EXCEED THE SPECIFIED VALUE AND THAT IT IS REGULATING
SAFETY PURPOSE OF THE POLARIZED LINE PLUG HAS NOT BEEN CORRECTLY, WE SUGGEST THAT YOU AND YOUR SERVICE ORGA-
DEFEATED. NIZATION REVIEW TEST PROCEDURES SO THAT VOLTAGE REGU-
LATION IS ALWAYS CHECKED AS A STANDARD SERVICING PROCE-
3. SOLDERING MUST BE INSPECTED TO DISCOVER POSSIBLE COLD DURE. AND THAT THE HIGH VOLTAGE READING BE RECORDER ON
SOLDER JOINTS, SOLDER SPLASHES OR SHARP SOLDER POINTS. EACH CUSTOMER'S INVOICE.
BE CERTAIN TO REMOVE ALL LOOSE FOREIGN PARTICLES.
5. WHEN TROUBLESHOOTING AND MAKING TEST MEASUREMENTS IN
4. CHECK FOR PHYSICAL EVIDENCE OF DAMAGE OR DETERIORATION A PRODUCT WITH A PROBLEM OF EXCESSIVE HIGH VOLTAGE,
TO PARTS AND COMPONENTS. FOR FRAYED LEADS, DAMAGED AVOID BEING UNNECESSARILY CLOSE TO THE PICTURE TUBE AND
INSULATION (INCLUDING A.C. CORD). AND REPLACE IF NECESSARY THE HIGH VOLTAGE SUPPLY. DO NOT OPERATE THE PRODUCT
FOLLOW ORIGINAL LAYOUT, LEAD LENGTH AND DRESS. LONGER THAN IS NECESSARY TO LOCATE THE CAUSE OF EXCES
5. NO LEAD OR COMPONENT SHOULD TOUCH A RECIVING TUBE OR SIVE VOLTAGE.
A RESISTOR RATED AT 1 WATT OR MORE. LEAD TENSION AROUND 6. REFER TO HV. B+ AND SHUTDOWN ADJUSTMENT PROCEDURES
PROTRUNING METAL SURFACES MUST BE AVOIDED. DESCRIBED IN THE APPROPRIATE SCHEMATIC AND DIAGRAMS
6. ALL CRITICAL COMPONENTS SUCH AS FUSES, FLAMEPROOF (WHERE USED).
RESISTORS, CAPACITORS, ETC. MUST BE REPLACED WITH EXACT SUBJECT: IMPLOSION
FACTORY TYPES, DO NOT USE REPLACEMENT COMPONENTS
OTHER THAN THOSE SPECIFIED OR MAKE UNRECOMMENDED CIR- 1. ALL DIRECT VIEWED PICTURE TUBES ARE EQUIPPED WITH AN INTE
CUIT MODIFICATIONS. GRAL IMPLOSION PROTECTION SYSTEM, BUT CARE SHOULD BE
TAKEN TO AVOID DAMAGE DURING INSTALLATION, AVOID
7. AFTER RE-ASSEMBLY OF THE SET ALWAYS PERFORM AN A.C. SCRATCHING THE TUBE. IF SCRATCHED REPLACE IT.
LEAKAGE TEST ON ALL EXPOSED METALLIC PARTS OF THE CABI-
NET, (THE CHANNEL SELECTOR KNOB, ANTENNA TERMINALS. HAN- 2. USE ONLY RECOMMENDED FACTORY REPLACEMENT TUBES.
DLE AND SCREWS) TO BE SURE THE SET IS SAFE TO OPERATE SUBJECT : TIPS ON PROPER INSTALLATION
WITHOUT DANGER OF ELECTRICAL SHOCK. DO NOT USE A LINE 1. NEVER INSTALL ANY PRODUCT IN A CLOSED-IN RECESS, CUBBY-
ISOLATION TRANSFORMER DURING THIS TEST USE AN A.C. VOLT- HOLE OR CLOSELY FITTING SHELF SPACE. OVER OR CLOSE TO
METER, HAVING 5000 OHMS PER VOLT OR MORE SENSITIVITY, IN HEAT DUCT, OR IN THE PATH OF HEATED AIR FLOW.
THE FOLLOWING MANNER; CONNECT A 1500 OHM 10 WATT RESIS-
TOR, PARALLELED BY A .15 MFD. 150.V A.C TYPE CAPACITOR 2. AVOID CONDITIONS OF HIGH HUMIDITY SUCH AS: OUTDOOR PATIO
BETWEEN A KNOWN GOOD EARTH GROUND (WATER PIPE, CON- INSTALLATIONS WHERE DEW IS A FACTOR, NEAR STEAM RADIA-
DUIT, ETC.) AND THE EXPOSED METALLIC PARTS, ONE AT A TIME. TORS WHERE STEAM LEAKAGE IS A FACTOR, ETC.
MEASURE THE A.C. VOLTAGE ACROSS THE COMBINATION OF 1500 3. AVOID PALCEMENT WHERE DRAPERIES MAY OBSTRUCT REAR
OHM RESISTOR AND .15 MFD CAPACITOR. REVERSE THE A.C. PLUG VENTING. THE CUSTOMER SHOULD ALSO AVOID THE USE OF DEC-
AND REPEAT A.C. VOLTAGE MEASUREMENTS FOR EACH EXPOSED ORATIVE SCARVES OR OTHER COVERINGS WHICH MIGHT
METALLIC PART. VOLTAGE MEASURED MUST NOT EXCEED 75 OBSTRUCT VENTILATION.
VOLTS R.M.S. THIS CORRESPONDS TO 0.5 MILLIAMP A.C ANY
4. WALL AND SHELF MOUNTED INSTALLATIONS USING A COMMER-
VALUE EXCEEDING THIS LIMIT CONSTITUTES A POTENTIAL SHOCK
CIAL MOUNTING KIT. MUST FOLLOW THE FACTORY APPROVED
HAZARD AND MUST BE CORRECTED IMMEDIATELY.
MOUNTING INSTRUCTIONS A PRODUCT MOUNTED TO A SHELF OR
A.C. VOLTMETER PLATFORM MUST RETAIN ITS ORIGINAL FEET (OR THE EQUIVALENT
THICKNESS IN SPACERS) TO PROVIDE ADEQUATE AIR FLOW
ACROSS THE BOTTOM, BOLTS OR SCREWS USED FOR FASTENERS
MUST NOT TOUCH ANY PARTS OR WIRING. PERFORM LEAKAGE
TEST ON CUSTOMIZED INSTALLATIONS.
5. CAUTION CUSTOMERS AGAINST THE MOUNTING OF A PRODUCT ON
SLOPING SHELF OR A TILTED POSITION, UNLESS THE PRODUCT IS
PROPERLY SECURED.
GOOD EARTH GROUND PLACE THIS PROBE 6. A PRODUCT ON A ROLL-ABOUT CART SHOULD BE STABLE ON ITS
SUCH AS THE WATER ON EACH EXPOSED MOUNTING TO THE CART. CAUTION THE CUSTOMER ON THE HAZ-
PIPE. CONDUIT. ETC METAL PART ARDS OF TRYING TO ROLL A CART WITH SMALL CASTERS ACROSS
THRESHOLDS OR DEEP PILE CARPETS.
7. CAUTION CUSTOMERS AGAINST THE USE OF A CART OR STAND
SUBJECT: GRAPHIC SYMBOLS WHICH HAS NOT BEEN LISTED BY UNDERWRITERS LABORATORIES,
THE LIGHTNING FLASH WITH APROWHEAD SYMBOL. WITHIN INC. FOR USE WITH THEIR SPECIFIC MODEL OF TELEVISION
AN EQUILATERAL TRIANGLE, IS INTENDED TO ALERT THE RECEIVER OR GENERICALLY APPROVED FOR USE WITH T.V.'S OF
SERVICE PERSONNEL TO THE PRESENCE OF UNINSULATED THE SAME OR LARGER SCREEN SIZE.
"DANGEROUS VOLTAGE" THAT MAY BE OF SUFFICIENT MAG-
8. CAUTION CUSTOMERS AGAINST THE USE OF EXTENSION CORDS,
NITUDE TO CONSTITUTE A RISK OF ELECTRIC SHOCK.
EXPLAIN THAT A FOREST OF EXTENSIONS SPROUTING FROM A SIN-
THE EXCLAMATION POINT WITHIN AN EQUILATERAL TRIAN- GLE OUTLET CAN LEAD TO DISASTROUS CONSEQUENCES TO
GLE IS INTENDED TO ALERT THE SERVICE PERSONNEL TO HOME AND FAMILY.
THE PRESENCE OF IMPORTANT SAFETY INFORMATION IN
SERVICE LITERATURE.
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SERVICING PRECAUTIONS
CAUTION : Before servicing the DVD covered by this service Electrostatically Sensitive (ES) Devices
data and its supplements and addends, read and follow the Some semiconductor (solid state) devices can be damaged
SAFETY PRECAUTIONS. NOTE : if unforeseen circum- easily by static electricity. Such components commonly are
stances create conflict between the following servicing pre- called Electrostatically Sensitive (ES) Devices. Examples of
cautions and any of the safety precautions in this publica- typical ES devices are integrated circuits and some field
tions, always follow the safety precautions. effect transistors and semiconductor chip components.
Remembers Safety First: The following techniques should be used to help reduce the
incidence of component damage caused by static electricity.
General Servicing Precautions
1. Always unplug the DVD AC power cord from the AC 1. Immediately before handling any semiconductor compo-
power source before: nent or semiconductor-equipped assembly, drain off any
(1) Removing or reinstalling any component, circuit board, electrostatic charge on your body by touching a known
module, or any other assembly. earth ground. Alternatively, obtain and wear a commer-
(2) Disconnection or reconnecting any internal electrical cially available discharging wrist strap device, which
plug or other electrical connection. should be removed for potential shock reasons prior to
(3) Connecting a test substitute in parallel with an elec- applying power to the unit under test.
trolytic capacitor.
Caution : A wrong part substitution or incorrect 2. After removing an electrical assembly equipped with ES
polarity installation of electrolytic capacitors may result devices, place the assembly on a conductive surface such
in an explosion hazard. as aluminum foil, to prevent electrostatic charge buildup or
exposure of the assembly.
2. Do not spray chemicals on or near this DVD or any of
its assemblies. 3. Use only a grouned-tip soldering iron to solder or unsolder
ES devices.
3. Unless specified otherwise in this service data, clean
electrical contacts by applying an appropriate contact 4. Use only an anti-static solder removal device. Some
cleaning solution to the contacts with a pipe cleaner, solder removal devices not classified a "anti-static" can
cotton-tipped swab, or comparable soft applicator. generate electrical charges sufficient to damage ES
Unless specified otherwise in this service data, lubrication devices.
of contacts is not required.
5. Do not use freon-propelled chemicals. These can
4. Do not defeat any plug/socket B+ voltage interlocks with generate electrical charge sufficient to damage ES
whitch instruments covered by this service manual might devices.
be equipped.
6. Do not remove a replacement ES device from its protec
5. Do not apply AC power to this DVD and/or any of its tive package until immediately before you are ready to
electrical assemblies unless all solid-state device heat install it. (Most replacement ES devices are packaged with
sinks are cerrectly installed. leads electrically shorted together by conductive foam,
aluminum foil, or comparable conductive material).
6. Always connect test instrument ground lead to the
appropriate ground before connection the test instrument
positive lead. Always remove the test instrument ground 7. Immediately before removing the protective material from
lead last. the leads of a replacement ES device, touch the protective
material to the chassis or circuit assembly into which the
Insulation Checking Procedure device will be installed.
Disconnect the attachment plug from the AC outlet and turn
the power on. Connect an insulation resistance meter(500V) Caution : Be sure no power is applied to the chassis or
to the blades of the attachment plug. The insulation resis- circuit, and observe all other safety precautions.
tance between each blade of the attachment plug and acces-
sible conductive parts (Note 1) should be more than 1M- 8. Minimize bodily motions when handling unpackaged
ohm. replacement ES devices. (Normally harmless motion such
Note 1 : Accessible Conductive Parts including Metal pan- as the brushing together of your clothes fabric or the lifting
els, Input terminals, Earphone jacks, etc. of your foot from a carpeted floor can generate static elec-
tricity sufficient to damage an ES device.)
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