Service Manual HITACHI 53SBX10B PROJECTION Color Television

APRIL 2001 HHEA-MANUFACTURING DIVISION PA No. 0145 60DX10B 50GX30B 50DX10B 43GX10B R/C: CLU-4311UG NTSC HP11 HP12 Chassis SERVICE MANUAL CONTENTS IMPORTANT SAFETY INSTRUCTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 SERVICING PRECAUTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 TECHNICAL CAUTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 SPECIFICATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 CIRCUIT PROTECTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 CAUTIONS WHEN CONNECTING/DISCONNECTING THE HV CONNECTOR . . . . . .12 GENERAL INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13 REMOTE CONTROL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14 CUSTOMIZED PICTURE AND SOUND ADJUSTMENTS . . . . . . . . . . . . . . . . . . . . . .15 SERVICE ADJUSTMENTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19 ADJUSTMENT LOCATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .35 TROUBLESHOOTING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .40 WAVEFORMS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .47 DC VOLTAGE TABLES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .51 PROTECTION CIRCUIT BLOCK DIAGRAM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .59 BASIC CIRCUIT DIAGRAM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .60 PRINTED CIRCUIT BOARDS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .76 BLOCK DIAGRAM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .90 WIRING DIAGRAM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .91 CHASSIS WIRING DRAWING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .93 EXPLODED VIEW . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .94 REPLACEMENT PARTS LIST . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .96 QUICK REFERENCE PARTS LIST . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .118 CAUTION: These servicing instructions are for use by qualified service personnel only. To reduce the risk of electric shock do not perform any servicing other than that contained in the operating instructions unless you are qualified to do so. Before servicing this chassis, it is important that the service technician read the “IMPORTANT SAFETY INSTRUCTIONS” in this service manual. SAFETY NOTICE USE ISOLATION TRANSFORMER WHEN SERVICING Components having special safety characteristics are identified by a on the schematics and on the parts list in this Service Data and its supplements and bulletins. Before servicing the chassis, it is important that the service technician read and follow the “Important Safety Instructions” in this Service Manual. PROJECTION COLOR TELEVISION SPECIFICATIONS AND PARTS ARE SUBJECT TO CHANGE FOR IMPROVEMENT !

2 Components having special safety characteristics are identified by a on the schematics and on the parts list in this service manual and its supplements and bulletins. Before servicing this chassis, it is important that the service technician read and follow the “Important Safety Instructions” in this Service Manual. For continued X-Radiation protection, replace picture tube with original type or Hitachi approved equivalent type. This Service Manual is intended for qualified service technicians; it is not meant for the casual do-it-yourselfer. Qualified technicians have the necessary test equipment and tools, and have been trained to properly and safely repair complex products such as those covered by this manual. Improperly performed repairs can adversely affect the safety and reliability of the product and may void warranty. If you are not qualified to perform the repair of this product properly and safely, you should not risk trying to do so and refer the repair to a qualified service technician. WARNING Lead in solder used in this product is listed by the California Health and Welfare agency as a known reproductive toxicant which may cause birth defects or other reproductive harm (California Health and Safety Code, Section 25249.5). When servicing or handling circuit boards and other components which contain lead in solder, avoid unprotected skin contact with solder. Also, when soldering do not inhale any smoke or fumes produced. This television receiver provides display of television closed captioning in accordance with section 15.119 of the FCC rules. FEDERAL COMMUNICATIONS COMMISSION NOTICE This equipment has been tested and found to comply with the limits for a Class B digital device, pursuant to Part 15 of the FCC Rules. These limits are designed to provide reasonable protection against harmful interference in a residential installation. This equipment generates, uses, and can radiate radio frequency energy and, if not installed and used in accordance with the instructions, may cause harmful interference to radio communications. However, there is no guarantee that interference will not occur in a particular installation. If this equipment does cause harmful interference to radio or television reception, which can be determined by turning the equipment off and on, the user is encouraged to try to correct the interference by one or more of the following measures: ¥ Reorient or relocate the receiving antenna. ¥ Increase the separation between the equipment and the receiver. ¥ Connect the equipment into an outlet on a circuit different from that to which the receiver is connected. ¥ Consult the dealer or an experienced radio/television technician for help. IMPORTANT SAFETY INSTRUCTIONS USE ISOLATION TRANSFORMER WHEN SERVICING !

3 IMPORTANT SAFETY INSTRUCTION 1. Before returning an instrument to the customer, always make a safety check of the entire instrument, including but not limited to the following items. a. Be sure that no built-in protective devices are defective and/or have been deleted during servicing. (1) Protective shields are provided on this chassis to protect both the technician and the customer. Correctly replace all missing protective shields, including any removed for servicing convenience. (2) When reinstalling the chassis and/or other assembly in the cabinet, be sure to put back in place all protective devices, including but not limited to, nonmetallic control knobs, insulating fishpaper, adjustment and compartment covers/shields, and isolation resistor/capacitor networks. Do not operate this instrument or permit it to be operated without all protective devices correctly installed and functioning. Servicers who defeat safety features or fail to perform safety checks may be liable for any resulting damage. b. Be sure that there are no cabinet openings through which an adult or child might be able to insert their fingers and contact a hazardous voltage. Such openings include, but are not limited to (1) spacing between the picture tube and cabinet mask, (2) excessively wide cabinet ventilation slots, and (3) an improperly fitted and/or incorrectly secured cabinet back cover. c. Antenna Cold Check — With the instrument AC plug removed from any AC source, connect an electrical jumper across the two AC plug prongs. Place the instrument AC switch in the on position. Connect one lead of an ohmmeter to the AC plug prongs tied together and touch the other ohmmeter lead in turn to each tuner antenna input, exposed terminal screw and, if applicable, to the coaxial connector. If the measured resistance is less than 1.0 megohms or greater than 5.2 megohms, an abnormality exists that must be corrected before the instrument is returned to the customer. Repeat this test with the instrument AC switch in the off position. d. Leakage Current Hot Check — With the instrument completely reassembled, plug the AC line cord directly into a 120V AC outlet. (Do not use an isolation transformer during this test.) Use a leakage current tester or a metering system that complies with American National Standards Institute (ANSI) C101.0 Leakage Current for Appliances and Underwriters Laboratories (UL) 1410, (50.7). With the instrument AC switch first in the on position and then in the off position, measure from a known earth ground (metal waterpipe, conduit, etc.) to all exposed metal parts of the instrument (antennas, handle bracket, metal cabinet, screw heads, metallic overlays, control shafts, etc.), especially any exposed metal parts that offer an electrical return path to the chassis. Any current measured must not exceed 0.5 milliamps. Reverse the instrument power cord plug in the outlet and repeat test. ANY MEASUREMENTS NOT WITHIN THE LIMITS SPECIFIED HEREIN INDICATE A POTENTIAL SHOCK HAZARD THAT MUST BE ELIMINATED BEFORE RETURNING THE INSTRUMENT TO THE CUSTOMER OR BEFORE CONNECTING THE ANTENNA OR ACCESSORIES. e. High Voltage — This receiver is provided with a hold down circuit for clearly indicating that voltage has increased in excess of a predetermined value. Comply will all notes described in this Service Manual regarding this hold down circuit when servicing, so that this hold down circuit may correctly be operated. f. Service Warning — With maximum contrast, operating high voltage in this receiver is lower than 31.5 kV. In case any component having influence on high voltage is replaced, confirm that the high voltage with maximum contrast is lower than 31.5 kV. To measure H.V. use a high impedance H.V. meter. Connect (-) to chassis earth and (+) to the CRT anode button. (See the following connection diagram.) Note: Turn power switch off without fail before the connection to the anode button is made. LEAKAGE CURRENT TESTER (READING SHOULD NOT BE ABOVE 0.5mA) EARTH GROUND TEST ALL EXPOSED METAL SURFACES DEVICE UNDER TEST 2-WIRE CORD ALSO TEST WITH PLUG REVERSED (USING AC ADAPTER PLUS AS REQUIRED) Chassis ground High Impedance H.V. meter Deflection P.W.B. FBT (TH01) High voltage connector AC Leakage Test

4 g. X-radiation – TUBE: The primary source of X- radiation in this receiver is the picture tube. The tube utilized for the above mentioned function in this chassis is specially constructed to limit X-radiation emissions. For continued X-radiation protection, the replacement tube must be the same type as the original, Hitachi approved type. When troubleshooting and making test measurements in a receiver with a problem of excessive high voltage, avoid being unnecessarily close to the picture tube and the high voltage component. Do not operate the chassis longer than is necessary to locate the cause of excessive voltage. h. X-radiation Shield – 1. This receiver is provided with X-ray shield plates for protection against X-radiation. Do not remove X-ray shield plates A, B, or C shown in Fig. 1 unnecessarily, when troubleshooting and/or making test measurements. 2. To prevent X-radiation, after replacement of picture tube and lens, confirm these components to be fixed correctly to bracket and cabinet, and not to be taken off easily. Shield Plate A Glass Lens for Shielding Shield Plate B Shield Plate C Shield Plate D Detailing X-radiation shield Shield Plate C Fig. 1. Installation of shield lens, shield cover and shield plates (oblique view). IMPORTANT SAFETY INSTRUCTIONS

5 2. Read and comply with all caution and safety-related notes on or inside the receiver cabinet, on the receiver chassis, or on the picture tube. 3. Design Alteration Warning – Do not alter or add to the mechanical or electrical design of this TV receiver. Design alterations and additions including but not limited to circuit modifications and the addition of items such as auxiliary audio and/or video output connectors, might alter the safety characteristics of this receiver and create a hazard to the user. Any design alterations or additions may void the manufacturer’s warranty and may make you, the servicer, responsible for personal injury or property damage resulting therefrom. 4. Picture Tube Implosion Protection Warning – The picture tube in this receiver employs integral implosion protection. For continued implosion protection, replace the picture tube only with one of the same type number. Do not remove, install, or otherwise handle the picture tube in any manner without first putting on shatterproof goggles equipped with side shields. People not so equipped must be kept safely away while picture tubes are handled. Keep the picture tube away from your body. Do not handle the picture tube by its neck. 5. Hot Chassis Warning – a. Some TV receiver chassis are electrically connected directly to one conductor of the AC power cord and may be safely serviced without an isolation transformer only if the AC power plug is inserted so that the chassis is connected to the ground side of the AC power source. Confirm that the AC power plug is inserted correctly with an AC voltmeter by measuring between the chassis and a known earth ground. If a voltage reading in excess of 1.0V is obtained, remove and reinsert the AC power plug in the opposite polarity and again measure the voltage potential between the chassis and a known earth ground. b. Some TV receiver chassis normally have 85V AC (RMS) between chassis and earth ground regardless of the AC plug polarity. These chassis can be safely serviced only with an isolation transformer inserted in the power line between the receiver and the AC power source, for both personnel and test equipment protection. c. Some TV receiver chassis have a secondary ground system in addition to the main chassis ground. This secondary ground system is not isolated from the AC power line. The two ground systems are electrically separated by insulating material that must not be defeated or altered. 6. Observe original lead dress. Take extra care to assure correct lead dress in the following areas: a. near sharp edges, b. near thermally hot parts – be sure that leads and components do not touch thermally hot parts, c. the AC supply, d. high voltage and e. antenna wiring. Always inspect in all areas for pinched, out-of- plate, or frayed wiring. Do not change spacing between components and the printed circuit board. Check AC power cord for damage. 7. Components, parts, and/or wiring that appear to have overheated or are otherwise damaged should be replaced with components, parts, or wiring that meet original specifications. Additionally, determine the cause of overheating and/or damage and, if necessary, take corrective action to remove any potential safety hazard. 8. PRODUCT SAFETY NOTICE – Many TV electrical and mechanical parts have special safety-related characteristics some of which are often not evident from visual inspection, nor can the protection they give necessarily be obtained by replacing them with components rated for higher voltage, wattage, etc. Parts that have special safety characteristics are identified in Hitachi service data by shading on schematics and by a in the parts list. Use of substitute replacement that does not have the same safety characteristics as the recommended replacement part in Hitachi service data parts list might create shock, fire, and/or other hazards. Product safety is under review continuously and new instructions are issued whenever appropriate. For the latest information, always consult the appropriate current Hitachi service literature. A subscription to, or additional copies of service literature may be obtained at a nominal charge from Hitachi. ! IMPORTANT SAFETY INSTRUCTIONS

6 CAUTION: Before servicing instruments covered by this service data and its supplements and addenda, read and follow the “Important Safety Instructions” on page 3 of this publication. NOTE: If unforeseen circumstances create conflict between the following servicing precautions and any of the safety precautions on page 3 of this publication, always follow the safety precautions. Remember: Safety First. General Servicing Guidelines 1. Always unplug the instrument AC power cord from the AC power source before: a. Removing or reinstalling any component, circuit board, module, or any other instrument assembly. b. Disconnecting or reconnecting any instrument electrical plug or other electrical connection. c. Connecting a test substitute in parallel with an electrolytic capacitor in the instrument. CAUTION: A wrong part substitution or incorrect polarity installation of electrolytic capacitors may result in an explosion hazard. d. Discharging the picture tube anode. 2. Test high voltage only by measuring it with an appropriate high voltage meter or other voltage measuring device (DVM, FETVOM, etc.) equipped with a suitable high voltage probe. Do not test high voltage by “drawing an arc.” The H.V. Distribution Box has an internal 400MW resistor (bleeder resistor) connected from the high voltage to ground. After power is removed from the instrument the high voltage will discharge through the high voltage bleeder resistor. If the tubes have high voltage after power is removed, then the bleeder resistor is defective or the bleeder ground is disconnected. 3. Discharge the picture tube’s anode at any of the R, G, or B outputs on the H.V. Distribution Box only by (a) first connecting one end of an insulated clip lead to the degaussing or kine aquadag grounding system shield at the point where the picture tube socket ground lead is connected, and then (b) touch the other end of the insulated clip lead to the picture tube high voltage distribution box R, G, or B output, using an insulated handle to avoid personal contact with high voltage. 4. Do not spray chemicals on or near this instrument or any of its assemblies. 5. Unless specified otherwise in these service data, clean electrical contracts by applying the following mixture to the contacts with a pipe cleaner, cotton-tipped stick or comparable nonabrasive applicator: 10% (by volume) Acetone and 90% (by volume) isopropyl alcohol (90%- 99% strength). CAUTION: This is a flammable mixture. Unless specified otherwise in these service data, lubrication of contacts is not required. 6. Do not defeat any plug/socket B+ voltage interlocks with which instruments covered by this service data might be equipped. 7. Do not apply AC power to this instrument and/or any of its electrical assemblies unless all solid-state device heat- sinks are correctly installed. 8. Always connect the test instrument ground lead to the appropriate instrument chassis ground before connecting the test instrument positive lead. Always remove the test instrument ground lead last. 9. Use with this instrument only the test fixtures specified in this service data. CAUTION: Do not connect the test fixture ground strap to any heatsink in this instrument. Electrostatically Sensitive (ES) Devices Some semiconductor (solid state) devices can be damaged easily by static electricity. Such components commonly are called Electrostatically Sensitive (ES) Devices. Examples of typical ES devices are integrated circuits and some field- effect transistors and semiconductor “chip” components. The following techniques should be used to help reduce the incidence of component damage caused by static electricity. 1. Immediately before handling any semiconductor component or semiconductor-equipped assembly, drain off any electrostatic charge on your body by touching a known earth ground. Alternatively, obtain and wear a commercially available discharging wrist strap device, which should be removed for potential shock reasons prior to applying power to the unit under test. 2. After removing an electrical assembly equipped with ES devices, place the assembly on a conductive surface such as aluminum foil, to prevent electrostatic charge buildup or exposure of the assembly. 3. Use only a grounded-tip soldering iron to solder or desolder ES devices. 4. Use only can anti-static type solder removal device. Some solder removal devices not classified as “anti- static” can generate electrical charges sufficient to damage ES device. 5. Do not use freon-propelled chemicals. These can generate electrical charges sufficient to damage ES devices. 6. Do not remove a replacement ES device from its protective package until immediately before you are ready to install it. (Most replacement ES devices are packaged with leads electrically shorted together by conductive foam, aluminum foil or comparable conductive material.) 7. Immediately before removing the protective material from the leads of a replacement ES device, touch the protective material to the chassis or circuit assembly into which the device will be installed. CAUTION: Be sure no power is applied to the chassis or circuit, and observe all other safety precautions. 8. Minimize bodily motions when handling unpackaged replacement ES devices. (Otherwise harmless motion such as the brushing together of your clothes fabric or the lifting of your foot from a carpeted floor can generate SERVICING PRECAUTIONS

7 General Soldering Guidelines 1. Use a grounded-tip, low-wattage soldering iron and appropriate tip size and shape that will maintain tip temperature within the range 500°F to 600°F. 2. Use an appropriate gauge of resin-core solder composed of 60 parts tin/40 parts lead. 3. Keep the soldering iron tip clean and well-tinned. 4. Thoroughly clean the surfaces to be soldered. Use a small wire-bristle (0.5 inch or 1.25 cm) brush with a metal handle. Do not use freon-propelled spray-on cleaners. 5. Use the following desoldering technique. a. Allow the soldering iron tip to reach normal temperature (500°F to 600°F). b. Heat the component lead until the solder melts. Quickly draw away the melted solder with an anti- static, suction-type solder removal device or with solder braid. CAUTION: Work quickly to avoid overheating the circuit board printed foil. 6. Use the following soldering technique. a. Allow the soldering iron tip to reach normal temperature (500°F to 600°F). b. First, hold the soldering iron tip and solder strand against the component lead until the solder melts. c. Quickly move the soldering iron tip to the junction of the component lead and the printed circuit foil, and hold it there only until the solder flows onto and around both the component lead and the foil. CAUTION: Work quickly to avoid overheating the circuit board printed foil or components. d. Closely inspect the solder area and remove any excess or splashed solder with a small wire-bristle brush. Removal 1. Desolder and straighten each IC lead in one operation by gently prying up on the lead with the soldering iron tip as the solder melts. 2. Draw away the melted solder with an anti-static suction- type solder removal device (or with solder braid) before removing the IC. Replacement 1. Carefully insert the replacement IC in the circuit board. 2. Carefully bend each IC lead against the circuit foil pad and solder it. 3. Clean the soldered areas with a small wire-bristle brush. (It is not necessary to reapply acrylic coating to areas.) “Small-signal” Discrete Transistor Removal/Replacement 1. Remove the defective transistor by clipping its leads as close as possible to the component body. 2. Bend into a “U” shape the end of each of three leads remaining on the circuit board. 3. Bend into a “U” shape the replacement transistor leads. 4. Connect to replacement transistor leads to the corresponding leads extending from the circuit board and crimp the “U” with long nose pliers to insure metal to metal contact, then solder each connection. Power Output Transistor Devices Removal/Replacements 1. Heat and remove all solder from around the transistor leads. 2. Remove the heatsink mounting screw (if so equipped). 3. Carefully remove the transistor from the circuit board. 4. Insert new transistor in circuit board. 5. Solder each transistor lead, and clip off excess lead. 6. Replace heatsink. Diode Removal/Replacement 1. Remove defective diode by clipping its leads as close as possible to diode body. 2. Bend the two remaining leads perpendicularly to the circuit board. 3. Observing diode polarity, wrap each lead of the new diode around the corresponding lead on the circuit board. 4. Securely crimp each connection and solder it. 5. Inspect (on the circuit board copper side) the solder joints of the two “original leads”. If they are not shiny, reheat them and, if necessary, apply additional solder. Use Solding Iron to Pry Leads IC Removal/Replacement Some Hitachi unitized chassis circuit boards have slotted holes (oblong) through which the IC leads are inserted and then bent flat against the circuit foil. When holes are the slotted type, the following technique should be used to remove and replace the IC. When working with boards using the familiar round hole, use the standard technique as outlined in paragraphs 5 and 6 above.

8 Fuses and Conventional Resistor Removal/Replacement 1. Clip each fuse or resistor lead at top of circuit board hollow stake. 2. Securely crimp leads of replacement component around stake 1/8 inch from top. 3. Solder the connections. CAUTION: Maintain original spacing between the replaced component and adjacent components and the circuit board, to prevent excessive component temperatures. Circuit Board Foil Repair Excessive heat applied to the copper foil of any printed circuit board will weaken the adhesive that bonds the foil to the circuit board, causing the foil to separate from, or “lift- off,” the board. The following guidelines and procedures should be followed whenever this condition is encountered. In Critical Copper Pattern Areas High component/copper pattern density and/or special voltage/current characteristics make the spacing and integrity of copper pattern in some circuit board areas more critical than in others. The circuit foil in these areas is designated as Critical Copper Pattern. Because Critical Copper Pattern requires special soldering techniques to ensure the maintenance of reliability and safety standards, contact your Hitachi personnel. At IC Connections To repair defective copper pattern at IC connections, use the following procedure to install a jumper wire on the copper pattern side of the circuit board. (Use this technique only on IC connections.) 1. Carefully remove the damaged copper pattern with a sharp knife. (Remove only as much copper as absolutely necessary.) 2. Carefully scratch away the solder resist and acrylic coating (if used) from the end of the remaining copper pattern. 3. Bend a small “U” in one end of a small-gauge jumper wire and carefully crimp it around the IC pin. Solder the IC connection. 4. Route the jumper wire along the path of the cut-away copper pattern and let it overlap the previously scraped end of the good copper pattern. Solder the overlapped area, and clip off any excess jumper wire. 1. Remove the defective copper pattern with a sharp knife. Remove at least 1/4 inch of copper, to ensure hazardous condition will not exist if the jumper wire opens. 2. Trace along the copper pattern from both wire sides of the pattern break and locate the nearest component directly connected to the affected copper pattern. 3. Connect insulated 20-gauge jumper wire from the nearest component on one side of the pattern break to the lead of the nearest component on the other side. Carefully crimp and solder the connections. CAUTION: Be sure the insulated jumper wire is dressed so that it does not touch components or sharp edges. Frequency Synthesis (FS) Tuning Systems 1. Always unplug the instrument AC power cord before disconnecting or reconnecting FS tuning system cables and before removing or inserting FS tuning system modules. 2. The FS tuner must never be disconnected from the FS tuning control module while power is applied to the instrument. 3. When troubleshooting intermittent problems that might be caused by defective cable connection(s) to the FS tuning system, remove the instrument AC power as soon as the defective connector is found and finish confirming the bad connection with a continuity test. This procedure will reduce the probability of electrical overstress of the FS system semi-conductor components. CRIMP AND SOLDER BARE JUMPER WIRE Install Jumper Wire and Solder DEFECTIVE COPPER REMOVED Insulated Jumper Wire At Other Connections Use the following technique to repair defective copper pattern at connections other than IC Pins. This technique involves the installation of a jumper wire on the component side of the circuit board.

9 Leadless Chip Components (surface mount) Chip components must be replaced with identical chips due to critical foil track spacing. There are no holes in the board to mount standard transistors or diodes. Some chip capacitor or resistor board solder pads may have holes through the board, however the hole diameter limits standard resistor replacement to 1/8 watt. Standard capacitors may also be limited for the same reason. It is recommended that identical chip components be used. . Chip resistors have a three digit numerical resistance code -1st and 2nd significant digits and a multiplier. Example: 162 = 1600 or 1.6KΩ resistor, 0 = 0Ω (jumper). Chip capacitors generally do not have the value indicated on the capacitor. The color of the component indicates the general range of the capacitance. Chip transistors are identified by a two letter code. The first letter indicates the type and the second letter, the grade of transistor. Chip diodes have a two letter identification code as per the code chart and are a dual diode pack with either common anode or common cathode. Check the parts list for correct diode number. Component Removal 1. Use solder wick to remove solder from component end caps or terminals. 2. Without pulling up, carefully twist the component with tweezers to break the adhesive. 3. Do not reuse removed leadless or chip components since they are subject to stress fracture during removal . Chip Component Installation 1. Put a small amount of solder on the board soldering pads. 2. Hold the chip component against the soldering pads with tweezers or with a miniature alligator clip and apply heat to the pad area with a 30 watt iron until solder flows. Do not apply heat for more than 3 seconds How to Replace Flat-lC —Required Tools— • Soldering iron • iron wire or small awl • De-solder braids • Magnifier 1. Remove the solder from all of the pins of a Flat-lC by using a de-solder braid. 2. Put the iron wire under the pins of the Flat-lC and pull it in the direction indicated while heating the pins using a soldering iron. A small awl can be used instead of the iron wire. 3. Remove the solder from all of the pads of the Fiat-lC by using a de-solder braid. 4. Position the new Flat-lC in place (apply the pins of the Flat-lC to the soldering pads where the pins need to be soldered). Properly determine the positions of the soldering pads and pins by correctly aligning the polarity symbol. 6. Check with a magnifier for solder bridge between the pins or for dry joint between pins and soldering pads. To remove a solder bridge, use a de-solder braid as shown in the figure below. NOTE: These components are affixed with glue. Be careful not to break or damage any foil under the component or at the pins of the ICs when removing. Usually applying heat to the component for a short time while twisting with tweezers will break the component loose. Chip Components TYPE GRADE C B E SOLDER CAPS TRANSISTOR CAPACITOR 1ST DIGIT 2ND DIGIT MULTIPLIER = 1600 = 1.6K ANODES MH DIODE RESISTOR SOLDER CAPS COMMON CATHODE De-Solder Braid Soldering Iron Soldering Iron Soldering Iron Soldering Iron Soldering Iron Soldering Iron De-Solder Braid Flat-IC Bridge Solder De-Solder Braid Iron Wire Pull Awl Polarity Symbol 5. Solder all pins to the soldering pads using a fine tipped soldering iron.

10 High Voltage limiter circuit operation check. 1. Turn off TV and connect jig as shown in Figure 2. 2. Set the AC input to 120V AC and turn on TV. 3. Confirm test pattern on CRT is a usable picture, then slowly adjust jig until the picture disappears and TV shuts down. 4. When the limiter circuit is operating properly, High Voltage will be less than 31.5 kV at 1.7mA when TV shuts down. 5. Turn off set immediately after checking circuit operation. 6. Unplug set for one minute to reset shutdown circuit. Remove jig and voltmeter. TECHNICAL CAUTIONS (TH01) Figure 2

Service Manual HITACHI 53SBX10B PROJECTION Color Television

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