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.
Page 7
LOCATION OF SCREEN AND FOCUS VR’S SCREEN VR FOCUS VR – 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. MUTE (Service mode display) 2. DISPLAYING THE ADJUSTMENT MENU 1) Press MENU button on TV.
Page 10
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 18) 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.
Page 12
ITEM ADJUSTMENT PROCEDURE HEIGHT 1. Receive NTSC signal. (HIT) 2. Call up the adjustment mode display and select the item HIT. 3. Press the VOLUME s or t button to get the picture so that top and bottom of video signal begin to lack. 4.
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 Lord BACK UP DATA: 1 button Up : 2 button Selet Green color: 3 button Left : 4 button...
Page 14
• Adjust right and left 5.5 horizontal lines of RETMA signal for picture screen size after adjustment. • On one vertical side, the ellipse encircling a tiger mark should contact the upper limit of screen and the 12th line should be visible at the screen bottom. NET GEOMETRY SCREEN SIZE 43H72 (874 655) 50H72 (1014 760) 317.6 368.8...
Page 15
NOTES In many cases, color misconvergence may be corrected by returning HIT and WID data in main deflection side to initial adjusting values. Following cases will surely require readjustment of convergence. CRT REPLACEMENT When CRT is replaced, main deflection readjustment and color matching are required. Perform following procedures.
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" 43" HIGH VOLTAGE AT ZERO BEAM: 31.0 kV 31.0 kV MAX HIGH VOLTAGE: 32.5 kV 32.5 kV Table-1 SERVICE MODE ADJUSTING ITEMS AND DATA IN THE SERVICE MODE: Item Name of adjustment Preset Data...
LOCATION OF CONTROLS (Representative : 50H72) TV front Remote sensor (Behind the screen) Behind the door Power Indicator T Sst MENU EXIT TV/VIDEO DEMO POWER Video Audio inputs TV/VIDEO POWER VOLUMET S (Video3) CHANNEL st DEMO MENU EXIT TV rear AUDIO CENTER CHANNEL IN ANT (75Ω)
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 PIP CH ENTER PIP 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 : 50H72/43H72 Capacitors ..... CD Ceramic Disk : Plastic Film : Electrolytic Resistors ....
Page 26
Location Location Location Location Location Location Location Location Location Location Parts No. Parts No. Description Description Parts No. Parts No. Description Description Parts No. Parts No. Parts No. Description Description Description Parts No. Parts No. Parts No. Description Description Description C423 24211222 CERAMIC DISC, 2KV B 2200PFK...
Page 28
Location Location Location Location Location Location Location Location Location Location Parts No. Parts No. Parts No. Parts No. Parts No. Description Description Description Description Description Parts No. Parts No. Parts No. Parts No. Parts No. Description Description Description Description Description C7794 24503041 PLASTIC FILM , 63V 0.1UF J...
Page 29
CH250 24092730 CERAMIC CHIP, 16V B 0.1UF K CH622 24590222 PLASTIC FILM, 50V 2200PF J CH301 24109472 CERAMIC CHIP, 50V B 4700PF K (43H72) CH623 24100103 CERAMIC CHIP, 50V F 10000PF Z CH302 24100104 CERAMIC CHIP, 25V F 100000PF Z (43H72)
Page 30
Location Location Location Location Location Location Location Location Location Location Parts No. Parts No. Parts No. Parts No. Parts No. Description Description Description Description Description Parts No. Parts No. Parts No. Parts No. Parts No. Description Description Description Description Description CS15 24436331 CERAMIC DISC, 50V SL 330PF J...
Page 33
Location Location Location Location Location Location Location Location Location Location Parts No. Parts No. Parts No. Parts No. Parts No. Description Description Description Description Description Parts No. Parts No. Parts No. Parts No. Parts No. Description Description Description Description Description R869 24366100 CARBON FILM, 1/6W 10 OHM J...
Page 34
Location Location Location Location Location Location Location Location Location Location Parts No. Parts No. Description Description Parts No. Parts No. Description Description Parts No. Parts No. Parts No. Description Description Description Parts No. Parts No. Parts No. Description Description Description R4533 24011331 CHIP, METAL FILM, 1/20W 330 OHM J...
Page 35
Location Location Location Location Location Location Location Location Location Location Parts No. Parts No. Parts No. Parts No. Parts No. Description Description Description Description Description Parts No. Parts No. Parts No. Parts No. Parts No. Description Description Description Description Description R9708 24366821 CARBON FILM, 1/6W 820 OHM J...
Page 36
CHIP, METAL FILM, 1/20W 1K OHM J RH212 24011473 CHIP, METAL FILM, 1/20W 47K OHM J (43H72) RH301 24011684 METAL FILM CHIP 1/20W 680K J (43H72) RH406 24011473 CHIP, METAL FILM, 1/20W 47K OHM J RH302 24011102 CHIP, METAL FILM, 1/20W 1K OHM J...
Page 37
Description Description RH421 24011681 CHIP, METAL FILM, 1/20W 680 OHM J RH648 24998103 CHIP, 1/16W 10K OHM (43H72) RH649 24011911 METAL FILM CHIP 1/20W 910 J RH422 24011102 CHIP, METAL FILM, 1/20W 1K OHM J RH661 24011911 METAL FILM CHIP 1/20W 910 J...
Page 42
Location Location Location Location Location Location Location Location Location Location Parts No. Parts No. Parts No. Parts No. Parts No. Description Description Description Description Description Parts No. Parts No. Parts No. Parts No. Parts No. Description Description Description Description Description D604 23118041 DIODE, MA111...
Page 43
Location Location Location Location Location Location Location Location Location Location Parts No. Parts No. Parts No. Parts No. Parts No. Description Description Description Description Description Parts No. Parts No. Parts No. Parts No. Parts No. Description Description Description Description Description DH313 23316666 DIODE, ZENER, MTZJ4.7B G101...
SCHEMATIC DIAGRAM MODEL : 43H72 50H72 WARNING: BEFORE SERVICING THIS CHASSIS, READ THE "X-RAY RADIATION PRECAUTION", "SAFETY PRECAUTION" AND "PRODUCT SAFETY NOTICE" ON THE MANUAL FOR THIS MODEL. CAUTION: The international hazard symbols "*" in the schematic diagram and the parts list designate components which have special characteristics important for safety and should be replaced only with types identical to those in the original circuit or specified in the parts list.
SPECIFICATIONS (Representative: 50H72) TELEVISION SYSTEM NTSC standard CHANNEL COVERAGE VHF: 2 through 13 UHF: 14 through 69 Cable TV: Mid band (A-8 through A-1, A through I) Super band (J through W) Hyper band (AA through ZZ, AAA, BBB) Ultra band (65 through 94, 100 through 125) POWER SOURCE 120 V AC, 60 Hz POWER CONSUMPTION...