CHAPTER 1 GENERAL ADJUSTMENTS SAFETY INSTRUCTIONS WARNING: BEFORE SERVICING THIS CHASSIS, READ THE “X-RAY RADIATION PRECAUTION”, “SAFETY PRECAU- TION” AND “PRODUCT SAFETY NOTICE” INSTRUCTIONS BELOW. X-RAY RADIATION PRECAUTION 1. Excessive high voltage can produce potentially hazardous 2. This receiver is equipped with a Fail Safe (FS) circuit which X-RAY RADIATION.
CRT ASSEMBLY REPLACEMENT AND MOUNTING CAUTION : DO NOT LOOSEN THE HEX HEAD BOLTS WITH SPRINGS (12 PCS), BECAUSE THOSE ARE FOR SEALING OF CRT COOLANT. Attention Serviceman The Hex Head Bolts with Springs. (see sketch) used on CRT assembly, 8 o’clock are “NOT”...
TO REMOVE CRT (Same procedure for R, G, B) 1. Remove CRT DRIVE Board, S. V. M. COIL and DEF. YOKE from CRT. 2. Remove Lens Assembly. 3. Detach CRT Anode Cap from CRT. 4. Remove CRT Assembly from CRT Mounting. Anode Cap CRT REPLACEMENT (Same procedure for R, G, B) Reverse the removal procedures except the followings.
WARNING : BEFORE SERVICING THIS CHASSIS, READ THE “X-RAY RADIATION PRECAUTION”, “SAFETY PRE- CAUTION” AND “PRODUCT SAFETY NOTICE” ON PAGE 3 OF THIS MANUAL. PICTURE TUBE COMPONENTS ADJUSTMENT DESCRIPTION OF NECK COMPONENTS TILT ADJUSTMENT Rotate R, G, B deflection yoke so that picture becomes hori- zon, then fasten screw.
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LOCATION OF SCREEN AND FOCUS VR’S SCREEN VR FOCUS VR Speaker grille – 7 –...
REPLACEMENT OF THE CRT Service parts are provided for each R, G and B. The contents of the parts are as follows. HITACHI 23008174 23008175 23008176 REPLACEMENT OF HIGH VOLTAGE CABLE 1. When replacing Anode Lead or Anode Cap with new one, remove Lead Holder from old lead as shown in figure ANODE LEAD below, and put it on new lead.
SERVICE MODE 1. ENTERING TO SERVICE MODE 1) Press MUTE button twice 2) Press MUTE button 3) While pressing the MUTE button, on Remote Control. again to keep pressing. press MENU button on TV set. 1/2 MUTE MUTE (Service mode display) 2.
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4. SELECTING THE ADJUSTING ITEMS 1) Every pressing of CHANNEL s button in the service mode changes the adjustment items in the order of table-2. (t button for reverse order) Refer to table-2 for preset data of adjustment mode. (See SETTING & ADJUSTING DATA on page 17) 5.
ELECTRICAL ADJUSTMENT ITEM ADJUSTMENT PROCEDURE ƒH 1. Receive NTSC signal. (free-running fre- 2. Short the terminal “TP +9V ” and the terminal “ TP (Free run) ” on the signal board with a jumper quency of Hor. wire. oscillator) 3. Connect the probe of frequency counter to the lead of R426 and GND. 4.
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ITEM ADJUSTMENT PROCEDURE HEIGHT 1. Receive NTSC signal. (HIT) 2. Select the "FULL" mode by PIC SIZE button on Remote Control. 3. Call up the adjustment mode display and select the item HIT. 4. Press the VOLUME s or t button to get the picture so that top and bottom of video signal begin to lack.
CONVERGENCE ADJUSTMENT Adjust convergence from center to circumference in order. 1. Select the adjustment mode following the steps on page KEY FUNCTION IN THE CONVERGENCE ADJUSTMENT: RCUT Up : 2 button Selet Green color: 3 button Left : 4 button Blinking of cursor ON/OFF: 5 button Right:...
SCREEN AND MIRROR ALIGNMENTS ASSEMBLING OF FRONT SCREEN MOUNTING OF FRONT SCREEN INSIDE 0 to 1 mm OUT SIDE K503 FRONT PANEL K501 K502 LENTICULAR FRESNAL <INSIDE> SMOOTH LENS FRESNEL LENTICULAR FRONT PANEL BLACK STRIPES <OUTSIDE> BLACK STRIPES SMOOTH BEZEL SPACER FRONT PANEL LENTICULAR...
CIRCUIT CHECKS HIGH VOLTAGE CHECK FS CIRCUIT CHECK CAUTION: There is no HIGH VOLTAGE ADJUSTMENT on The Fail Safe (FS) circuit check is indispensable for the final this chassis. Checking should be done following check in servicing. Checking should be done following the the steps below.
CHAPTER 2 SPECIFIC INFORMATIONS SETTING & ADJUSTING DATA SAFETY INSTRUCTIONS 50" HIGH VOLTAGE AT ZERO BEAM: 31.0 kV MAX HIGH VOLTAGE: 32.5 kV Table-1 SERVICE MODE ADJUSTING ITEMS AND DATA IN THE SERVICE MODE: Item Name of adjustment Preset Data Item Name of adjustment Preset...
LOCATION OF CONTROLS TV front Remort sensor (Behibd the screen) Channel ts Volume T S Menu tsT S Automatic Light Sensor VOL T SVOL POWER MENU POWER EXIT TV/VIDEO Video 3 Power indicator Video/audio inputs (behind the door) TOUCH FOCUS TV rear ANT (75 ) AUDIO CENTER...
Remote Control RECALL LIGHT RECALL POWER LIGHT POWER TV/CABLE/VCR switch MUTE TV/VIDEO TIMER CABLE Set to “TV” to control the TV. TIMER MUTE TV/VIDEO CHANNEL s/t Channel Number VOLUME s/t CH RTN CH RTN FAVORITE ADV/ PIC SIZE POP CH ENTER POP CH s MENU/...
PROGRAMMING CHANNEL MEMORY The channel memory is the list of TV channel numbers the TV tunes in when you press the CHANNEL s or t button. First, use the TV/CABLE and CH PROGRAM functions to preset all active channels in your area automatically. If necessary, arrange the preset channels with the ADD/ERASE functions so that you can tune into only desired channels.
The part number must be used when ordering parts, in order to assist in processing, be sure to include the Model number and Description. The PC board assembly with mark is no longer available after the end of the production. Models : 50H81 Capacitors ..... CD Ceramic Disk : Plastic Film : Electrolytic Resistors ....
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SIGNAL BOARD PD0073 BOTTOM (FOIL) SIDE – 53 – – 54 –...
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CONV-SEN BOARD PD0079 BOTTOM (FOIL) SIDE CRT DRIVE(RED) BOARD PD0080 BOTTOM (FOIL) SIDE – 61 –...
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CRT DRIVE(GRN) BOARD PD0080 BOTTOM (FOIL) SIDE CRT DRIVE(BLE) BOARD PD0080 BOTTOM (FOIL) SIDE – 62 –...
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SVM-R BOARD PD0080 BOTTOM (FOIL) SIDE SVM-G BOARD PD0080 BOTTOM (FOIL) SIDE SVM-B BOARD PD0080 BOTTOM (FOIL) SIDE – 63 –...
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FRONT BOARD PD0081 BOTTOM (FOIL) SIDE FRONT BOARD PD0081 BOTTOM (FOIL) SIDE FRONT BOARD PD0081 FRONT BOARD PD0081 BOTTOM (FOIL) SIDE BOTTOM (FOIL) SIDE – 64 –...