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Back to : Philco_PFS2908.pdf | Home FILE NO. SERVICE MANUAL Colour Television Model No. PFS2908 (Argentina) Service Ref. No. PFS2908-00 Specifications Product Code: 113020208 Power Source . . . . . . . . AC220V, 50Hz / 60Hz Receiving System . . . . . PAL (M/M, N/N), NTSC (M/M) Channel Coverage Antenna mode VHF: CH02-CH13, UHF: CH14-CH69 CATV mode VHF band: CH01-CH13, Mid band: CH14-CH22 Original Version Super band: CH23-CH36, Hyper band: CH37-CH64 Ultra band: CH65-CH94 and CH100-CH125 Low mid band: CH95-CH99 Chassis Series: LB6-A Video IF . . . . . . . . . . . . . 45.75MHz Aerial Input Impedance 75 Input Terminals AV1 (Video): Composite Video Input (Phone Jack) x 1 Give complete "SERVICE REF. NO." for S-Video Input (Separated Y/C) DIN 4-pin Jack x 1 parts order or servicing. It is shown on the AV1 (Audio):L/R Stereo Input (Phone Jack) x 1 set rating plate at the cabinet back of the unit. AV2 (Video):Composite Video Input (Phone Jack) x 1 AV2 (Audio):L/R Stereo Input (Phone Jack) x 1 set DVD (Video): Component Y, CB, CR Input (Phone Jack) x 1 set DVD (Audio): L/R Stereo Input (Phone Jack) x 1 set Output Terminals This T.V. receiver will not work properly in Video Monitor Output: Phono jack x 1 foreign countries where the television trans- Audio Monitor Output: L/R Stereo Output (Phone Jack) x 1 set mission system and power source differ from Headphone Jack: Mini stereo jack x 1 the design specifications. Refer to the speci- Sound Output (RMS) . . . 5W + 5W fication table. Speaker . . . . . . . . . . . . . . 6cm x 12cm x 2 pcs. Dimensions . . . . . . . . . . . 750(W) x 590(H) x 416.5(D) mm Weight . . . . . . . . . . . . . . . approx. 36.5 Kg Specifications subject to change without notice. BG4J Contents Safety Notice . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 Chassis Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 IC Block Diagrams . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-8 Service Adjustments. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-18 Cabinet Parts List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 Chassis Electrical Parts List. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20-27 Safety Notice SAFETY PRECAUTIONS 1: An isolation transformer should be connected in the 3: When replacing a chassis in the cabinet, always power line between the receiver and the AC line be certain that all the protective devices are when a service is performed on the primary of the installed properly, such as, control knobs, adjust- converter transformer of the set. ment covers or shields, barriers, isolation resistor- capacitor networks etc.. Before returning any 2: Comply with all caution and safety-related notes television to the customer, the service techni- provided on the cabinet back, inside the cabinet, on cian must be sure that it is completely safe the chassis or the picture tube. to operate without danger of electrical shock. X-RADIATION PRECAUTION The primary source of X-RADIATION in television receiver is the picture tube. The picture tube is specially con- structed to limit X-RADIATION emissions. For continued X-RADIATION protection, the replacement tube must be the same type as the original including suffix letter. Excessive high voltage may produce potentially hazard- ous X - RADIATION. To avoid such hazards, the high voltage must be maintained within specified limit. Refer to this service manual, high voltage adjustment for specific high voltage limit. If high voltage exceeds specified limits, take necessary corrective action. Carefully follow the instructions for + B1 volt power supply adjustment, and high voltage check to maintain the high voltage within the specified limits. PRODUCT SAFETY NOTICE Product safety should be considered when a component replacement is made in any area of a receiver. Components indicated by mark in the parts list and the schematic diagram designate components in which safety can be of special significance. It is particularly recommended that only parts designated on the parts list in this manual be used for component replacement designated by mark . No deviations from resistance wattage or voltage ratings may be made for replacement items designated by mark . -2- P10/21 +8V Antenna +5V +5VRC +8V CRT DRIVE KEY SW R/G/B CRT +5VRC R/G/B +200V +28V HV/Fo/Sc R/C PRE-AMP TUNER BUS H-OUT DY-H IF DY-V (LV76113) HORIZ-DRIVE HORIZ-OUT SAW filter E W OU T FBP IN FBT PLUSE SUSOC -16V +16V AV2/DVD/S-VIDEO C VIDEO -3- V- MONITOR OUT VIDEO V+ (LA78141-E/ LA7846NZ) S-VIDEO Y/AV1-V NJM2533MP VIDEO VERT-OUT +8V Chassis Block Diagrams AV1/AV2/DVD AUDIO IN AUDIO BUS 10V MONITOR OUT AUDIO AUDIO L/R +8V SIGNAL PROCESSING CIRCUIT +5V SPEAKER(L) SIF OUT (LA72703) L/R L +140V +32V AV1/AV2/DVD L/R L/R (LA42205-E) R AUDIO INPUT TC4052BFP +28V AC220V (SANKEN) AUDIO OUTPUT AUDIO-OUT SPEAKER(R) 10V POWER IC Block Diagrams IC601 POWER SUPPLY IC (STRW6754) FUNCTIONAL BLOCK DIAGRAM -4- IC Block Diagrams IC201 < IF/Video/Chroma/Def./CPU > LA76113 -5- IC Block Diagrams IC501 LA78141 IC001 LA42205 -6- LA72703 BTSC Decoder - Reference Apprication - OUT(L) OUT(R) Vcc 5V 10u MODE 10u Monitor 1u + + 100u 33n 33n 22u + 0.1? 2u2 4u7 4u7 4u7 4k7 0.1u IC3401LA72703 1u + 1u + + 47u + + + + 24 23 22 21 20 19 18 17 16 15 14 13 MODE OUT MUTE MATRIX IC Block Diagrams REGULATOR Spectral In Spectral DET Offset Cancel Wide RMS DET L+R L-R/SAP PILOT LEVEL DET -6dB LPF dbx processor MUTE STEREO PILOT L-R PLL CANCELLER DEMOD ST/SAP Offset SW LPF Cancell -7- SAP DEMOD Control SAP DET SYSTEM ST LPF SAP BPF CONTROL SAP PILOT DET DET Address SIF DEMOD IIC Spectral RMS DECODE GND 1 2 3 4 5 6 7 8 9 10 11 12 1u + 4u7 + + + 0.1u Address 4.5M 1u to Control 2u2 22u BPF 0.1u 560k IIC IIC 0.33u DATA CLOCK SIF SIGNAL from Tuner Slave Address = 80h ( 1000 000* ) :Pin8=OPEN/G Slave Address = 84h ( 1000 010* ) :Pin8=H IC Block Diagrams IC1001 TC4052BF IC1002 NJM2533M -8- Service Adjustments General This set has an On-screen Service Menu system included in the CPU that allows remote operation for most of the service adjustments. IC802 (EEPROM) Replacement When IC802 (EEPROM) is replaced, IC201 (CPU) will automatically write the initial reference data into IC802 for basic TV operation. However, the bus data should be checked and some bus data should be set up before attempting the service adjustments. (See pages 9 ~ 11 for detailed information.) Service Adjustment-1 1. Enter the Service Menu While pressing the MENU button on the television, press the Number Key 2 on the remote control unit. The Service Menu now appear. LB6A VER1.14 NO. NAME DATA Item No. 00 RFAGC 17H XX010111 MENU 1.11101111 2.11111000 Status Register Bit Allocations Item Name Data value CHANNEL UP [ Service Mode Display ] 2. Service Adjustments: Press the CHANNEL UP/DOWN button on the remote control handset to select the desired service menu item you want to adjust. VOLUME + VOLUME - Use the VOLUME + / - button to adjust the data. The + or - button will increase or decrease the data sequentially. CHANNEL DOWN 3. Exit from the Service Menu Press the MENU button to turn off the Service Menu display. The data which is set in the service mode is stored into the memory IC automatically. MENU -9- Service Adjustments On-screen Service Menu Following table shows the initial values which have been stored in the CPU ROM, and items for the service adjustments. When IC802 (EEPROM) is replaced, check the bus data to confirm they are the same as below. The shaded menu should be checked and be set up or readjusted according to the procedures described in the following pages. Initial Setup Data marked with an should be changed from Initial Value Data. No Item Description Initial Data Range 0 RFAGC Align RF AGC threshold 17 003F 1 HPHA Alignsynctoflybackphase 10 001F 2 VSIZE Align vertical amplitude 72 007F 3 V DC Align vertical DC bias 22 003F 4 VSIFT Align vertical position 08 000F 5 V LIN Align vertical linearity 0F 001F 6 V SC Align vertical S-correction 16 001F 7 VCOMP Align vertical size compensation 07 0007 8 EWDC Align East/West DC bias 33 003F 9 EWAMP Align East/West amplitude 06 003F 10 EWTIL Align East/West Trapezoid 32 003F 11 EWTOP Align East/West Top corner correction 01 000F 12 EWBOT Align East/West Bottom corner correction 02 000F 13 EWCSW Select control range for Corner correction 01 0001 14 HSCMP Align horizontal size compensation 07 0007 15 HBL Left H-Blanking Control 04 0007 16 HBR Right H-Blanking Control 05 0007 17 HPH60 Alignsynctoflybackphase(60Hzdata)03 003F 18 VSZ60 Align vertical amplitude (60Hz) FF 00FF 19 VDC60 Align vertical DC bias (60Hz) 00 007F 20 VSF60 Align vertical position (60Hz) 1D 001F 21 VLI60 Align vertical linearity (60Hz) 00 003F 22 VSC60 Align vertical S-correction (60Hz) 00 003F 23 VCO60 Align vertical size compensation (60Hz) 00 000F 24 EWD60 Align East/West DC bias (60Hz) 01 007F 25 EWA60 Align East/West amplitude (60Hz) 7F 007F 26 EWT60 Align East/West trapezoid (60Hz) 01 007F 27 EWB60 Align East/West Bottom corner correction (60Hz) 02 001F 28 EWP60 Align East/West Top corner correction (60Hz) 03 001F 29 CSW60 Select control range for Corner correction 00 0001 30 CMP60 Align horizontal size compensation 03 000F 31 T DIS Disable the Test SW & enable Audio / Video Mute SW 01 0001 32 HFREQ Align ES Sample horizontal frequency (MP is adjusted in the wafer line.) 40 007F 33 AFCG Selecthorizontalfirstloopgain&H-syncgatingon/off00 0001 34 AMUTE Disable audio outputs 00 0001 35 VMUTE Disable video outputs 00 0001 36 VSZ75 Enable 75% vertical size mode 00 0001 37 SKILL Force free-run mode 00 0001 38 VKILL Disable vertical mode 00 0001 -10- Service Adjustments No Item Description Initial Data Range 39 V SEP Select vertical sync. Separation sensitivity 00 0001 40 V RES Select Vertical Reset Timing 00 0001 41 HLOCK Select Vertical sync system 00 0001 42 VNSYN Enable IC Test Mode 00 0001 43 VTEST Select vertical DAC test mode 00 0003 44 CDMOD Select vertical countdown mode 00 0007 45 VIL T Vertical deinterlace SW 00 0001 46 VILT2 Vertical deinterlace SW2 00 0001 47 VBLKS V blanking control SW 01 0001 48 FBPSW Select Horizontal blanking operation 01 0001 49 AFCNG Enable AFC Low gain mode 00 0001 50 AFC2S Select FBP storage-timer tolerance level 00 0001 51 CRSBW Service Test Mode (normal/Cross/Black/White) 00 0003 52 DEINT Deinterlace 00 0001 53 OETST O/E.TEST 00 0001 54 RBIAS Align Red OUT DC level 03 00FF 55 GBIAS Align Green OUT DC level 1E 00FF 56 BBIAS Align Blue OUT DC level 02 00FF 57 RDRV Align Red OUT AC level 42 007F 58 GDRV Align Green OUT AC level 38 007F 59 BDRV Align Blue OUT AC level 3C 007F 60 White Balance 00FF 61 RD xx GD xx BD xx White Balance 007F 62 BLDEF Disable RGB output blanking 00 0001 63 SUBBI Align common RGB DC level 38 007F 64 VTRNS Enable data transmission between vertical retrace period 01 0001 65 DOSD Select Analogue OSD mode/Digital OSD mode 01 0001 66 EXCNT Align Ext. RGB amplitude 08 000F 67 OSDCN Align OSD AC level 05 0007 68 RGBSW Select the temperature characteristics for RGB DC output 01 0001 69 ACLDF Disable Contrast ABL 00 0001 70 ACLSW Changes inclination of Contrast ABL 00 0001 71 BABLD Disable brightness ABL 00 0001 72 MIDDF Disable brightness mid stop 00 0001 73 BABLT Align brightness ABL threshold 02 0007 74 RGBT Select RGB DAC test mode 00 000F 75 CLKSP Test Mode 00 0001 76 TSTMD Test Mode 00 0007 77 VXOAD VXO Adj. 04 0007 78 MCBCR Chroma Test Mode 00 0001 79 FODDS Select DDS mode 00 0001 80 CBCRI Select YCbCr Input 00 0001 81 CEXT Selected of chroma signal 00 0001 82 CBYPS Select chroma BPF bypass 00* 0001 83 CK ON C Kill Mode (0: Enable Killer circuit) 00 0001 -11- Service Adjustments No Item Description Initial Data Range 84 CKOFF Disable Killer circuit (for IC Test) 00 0001 85 CKOPE Select color killer operational level 04 0007 86 AUTOG Adjust Auto Green level 00 0007 87 TINTT Set tint center value 01* 0001 88 WBADJ Auto correct black level 00 0001 89 IDKIL Select color ident operational level 04 0007 90 CVCOA Control free Run frequency of chroma VCO 04 0007 91 CVCOC VCO free run mode 00 0001 92 FSCSP Select 10 pin output 01 0001 93 COLSY Select Color System 05* 0007 94 RBGAI R-Y/B-Y Gain Balance 07 000F 95 RBANG R-Y/B-Y Angle 05 000F 96 RYLEV R-Y DC Level (White-Balance) 07 001 97 BYLEV B-Y DC level (White-Balance) 08 001 98 GYAMP Adjust G-Y amplitude 08 000F 99 HTNCL Select color on/off at Half Tone Mode 00 0001 100 VXOFR VXO test mode 00 0001 101 VXOSB VXO test mode 00 0001 102 IFAGC Disable IF and RF AGC 00 0001 103 SVOSW Select pin 68 output 00 0001 104 STRSW Select sound trap ON/OFF 01 0001 105 VIFSY Select VIF Freq. 38.0/38.9/39.5/45.75/58.75MHz 03 0007 106 VLEV Align IF video level 04 0007 107 VCOFQ Align ES Sample IF VCO Frequency. (MP is adjusted in the wafer line) 60 00FF 108 AMOSW Select pin 70 output 00 0001 109 DEMTC Select De-emphasis Time Constant 01 0001 110 FMGAI Select FM Output Level 00 0001 111 A2SW West Germany Output Level 00 0001 112 SIFSY Select 4.5/5.5/6.0/6.5 MHz 00 0003 113 CHCON CH converter measure mode at India 00 0001 114 FMMUT Disable FM output 00 0001 115 AFTSE Select AFT sensitivity 10/13/20/40 [mV/KHz] 02 0003 116 IFTES IF Test mode 00 0001 117 VCOAD Fine adjust of IFVCO Free run 08 000F 118 EWTES Select East/West DAC test mode 00 0007 119 VOLFL Enablevolumefilter01 0001 120 VOL L Customer L-ch volume control 7F 007F 121 AUDSW Select audio input signal 00* 0003 122 CLKTS Operation CLK test modes 02 0003 123 SRCNT Select surround effect 00* 0003 124 DCCUT DC cut test modes 02 0003 125 MONOM Enable mono input mode 00 0001 126 VOL R Customer R-ch volume control 7F 007F 127 TOATT Enable tone attenuator 00 0001 -12- Service Adjustments No Item Description Initial Data Range 128 TBOST Select Boost/Cut of treble tone control 00* 0001 129 TRGAI Customer treble gain control 3F* 003F 130 PSEST Pseud Stereo 00 0001 131 BBOST Select Boost/Cut of bass tone control 00 0001 132 BAGAI Customer bass gain control 3F 003F 133 YFLSY Select Y Filter mode 00* 0003 134 CFLSY Select C Filter mode 00* 0003 135 Y APF Y APF 00* 0001 136 YDLAD Y Delay Adjust 04 0007 137 COGAI Select Coring Gain 03 0003 138 PRESH Select pre-shoot width 02 0003 139 OVRSH Select Over-shoot adjustment 02 0003 140 WPLOP Select White Peak Limiter level. (with Defeat) 00 0003 141 YGAMS Select Y Gamma start point. (with Defeat) 03 0003 142 DCRES Select luminace DC restoration 00 0003 143 BLKST Select Black Stretch Start Point (w/Defeat) 03 0003 144 BLKGA Select black stretch gain 00 0003 145 CTRAP Fine adjust of chroma trap 04 0007 146 CBPF Fine adjust of chroma BPF 01 0003 147 STRAP Fine adjust of sound trap 03 0007 148 YGAMG Select Y gamma gain 00 0003 149 GRAY Service Test Mode (White/Gray) 00 0001 150 YCMIX Select YC_C Input or 2.2V_DC Input 00 0001 151 TXTCC Select output by LPF or not 00 0001 152 VIDEO Video signal selector 00 0003 153 DLYTE DELAY Test 00 0001 154 SYSEP Select sync separation threshold level 03 0007 155 OPT1 OPTION1 ED 00FF 156 OPTPW AC SW ON Status 00 0001 157 MHOSD Horizontal position of OSD 2D 00FF 158 RFCOL Bias Color(RF) 00 00FF 159 RFBRI Bias Brightness(RF) 00 00FF 160 RFCON Bias Contrast(RF) 00 00FF 161 RFSHP Bias Sharpness(RF) 00 007F 162 DVDCL Bias Color(DVD) 1F 00FF 163 DVDBR Bias Brightness(DVD) 00 00FF 164 DVDCN Bias Contrast(DVD) 00 00FF 165 DVDSP Bias Sharpness(DVD) 00 007F 166 DVDRY Bias R-Y DC LEVEL (DVD) 3A 003F 167 DVDBY Bias R-Y DC LEVEL (DVD) 00 003F 168 CON60 CONTRAST(60Hz) 00 007F 169 BRI60 BRIGHT(60Hz) 00 007F 170 COL60 COLOR(60Hz) 00 007F 171 RBANT R-Y/B-Y ANGLE (NTSC) 04 001F 172 RBAV3 R-Y/B-Y ANGLE (VIDEO) 00 001F 173 POMT Power ON Video Mute Time 1A 007F -13- Service Adjustments No Item Description Initial Data Range 174 SYSAV Select sync separation threshold level for AV 04 0007 175 ZSIZ5 ZOOM VSIZE FOR 50HZ 0E 007F 176 ZSIZ6 ZOOM VSIZE FOR 60HZ 0E 007F 177 ZHPHA ZOOM HPHASE 00 001F 178 ZVSCO ZOOM VSC 00 001F 179 ZVLIN ZOOM VLIN 00 001F 180 ZEAM5 ZOOM EAST AMP FOR 50HZ 02 003F 181 ZEAM6 ZOOM EAST AMP FOR 50HZ 02 003F 182 ZCOLR ZOOM COLOR 00 003F 183 ZCONT ZOOM CONTRAST 00 003F 184 ZBRIT ZOOM BRIGHTNESS 00 003F 185 ZVPOS ZOOM V POSITION 00 000F 186 ZEWDC ZOOM EWDC 00 003F 187 ZEWTI ZOOM EAST/WEST TILT 00 003F 188 ZEWCT ZOOM East/West Corner Top 02 000F 189 ZEWCB ZOOM East/West Corner Bottom 02 000F 190 ZVSCP ZOOM V COMP 00 0007 191 ZHSCP ZOOM H.Size.Comp 00 000F 192 CAPCN CAPTION TEXT CONTRAST 06 0007 193 OPTAV OPTION FOR AV2 AV3 01 0001 194 OPTFS OPTION OF SLIM OR FLAT 01 0001 195 OBASS OFFSET OF BASS 00 000F 196 OTREB OFFSETOF TREBLE 04 000F 197 EWADJ East/West adjustment 198 VEADJ Vertical adjustment 199 ROMCR ROM CORRECTION 00 00FF -14- Service Adjustments Important Notice: Do not attempt to adjust service adjustments not listed on below otherwise it may cause loss of performance and for correct operation. Item 00 [RFAGC] AGC NOTE: Do not attempt this adjustment with weak signal. 1. Tune the receiver to most clearest (or strongest) VHF station in your area. Set the brightness and contrast Vertical centre controls to maximum. Set the colour control to mini- mum. 2. Select Item No. 01 [RFAGC] in the service mode. 3. Change value until the snow noise just disappears. Item 04 [VSHIFT] VERTICAL CENTRE 4. Exit from the service mode. 1. Receive a monochrome circular pattern. 2. Set the brightness and contrast to maximum. Item 01 [H-PHA] HORIZONTAL CENTRE 3. Select Item No. 04 [VSHIFT] in the service mode. 1. Receive a monochrome circular pattern. 4. Change value to be optimum vertical centre position. 2. Set the brightness and contrast to normal. 5. Exit from the service mode. 3. Select Item No. 02 [H-PHA] in the service mode. 4. Change value to be optimum horizontal centre posi- Item 08 [EWDC] HORIZONTAL WIDTH tion. 5. Exit from the service mode. 1. Receive a monochrome circular pattern. 2. Set the brightness and contrast to maximum. Horizontal centre 3. Select Item No.08 [EWDC] in the service mode. 4. Change value to be proper horizontal width. 5. Exit from the service mode. Item 02 [VSIZE] VERTICAL SIZE 1. Receive a monochrome circular pattern. 2. Set the brightness to normal and contrast to maximum. 3. Select Item No. 02 [VSIZE] in the service mode. Item 157 [MHOSD] OSD H-POSITION 4. Change value to be optimum vertical size. 1. Receive a monochrome circular pattern. 5. Exit from the service mode. 2. Set the brightness and contrast to normal. 3. Select Item No. 157 [MHOSD] in the service mode. Vertical size 4. Change value to be proper OSD horizontal position. 5. Exit from the service mode. Item 03 [V-DC] VERTICAL CENTRE 1. Receive a monochrome circular pattern. 2. Set the brightness and contrast to maximum. 3. Select Item No. 03 [V-DC] in the service mode. 4. Change value to be optimum vertical centre position. 5. Exit from the service mode. -15- Service Adjustments Items 35-42 GREY SCALE 1. Receive a monochrome circular pattern. 2. Set the brightness and colour to normal, contrast to maximum. 3. Enter to the service mode. 4. Set Item-54 RBIAS, 55 GBIAS and 56 BBIAS mode to 03, 1E and 02. Set Item-57 RDRV and 58 GDRV mode to 42 and 38, 59 BDRV to 3C. 5. Select Item-60 mode to be one horizontal scanning line and turn the screen volume on the FBT to obtain just vis- ible one coloured line. 6. Press the 1 (Red Bias +), 4 (Red Bias -), 2 (Green Bias +), 5 (Green Bias -), 3 (Blue Bias +) or 6 (Blue Bias -) button to adjust the brightness of each colour until a dim white line produced. Please see the control button alloca- tions in this mode. 7. Select Item-61 DRV mode to enter the white balance adjusting mode. 8. Press the 7 (Red Drive +), RECALL (Red Drive -), 8 (Green Drive +), 0 (Green Drive -), 9 (Blue Drive +) or SLEEP (Blue Drive -) button alternately to produce normal black and white picture. 9. Exit from the service mode. 10. Check for proper grey scale tracking at all brightness levels. NOTE: If the grey scale adjustment is made after picture tube replacement, check the high voltage. Green Bias + Green Bias - Red Drive - Red Drive + Blue Bias + Red Bias + Blue Bias - Red Bias - Blue Drive + Green Drive + Blue Drive - Green Drive - Press the MENU but- MAIN BOARD ton to exit from service mode SCREEN VR (Under side) -16- Service Adjustments Service Adjustment-3 FINE TUNING This adjustment is used to do a fine tuning of the channels with poor reception after they have been stored by the automatic tuning. This function is available for one channel only and the fine-tuned channel is memorized into IC802 (EEPROM). 1. Enter the Service Menu While pressing the MENU button on the television, press the "4" or MENU button on the remote control unit. The Service Menu now appear. MENU FINE TUNING - + [ Entering the Service Menu ] Fine tuning service mode 2. Service Adjustments: Press and hold the VOLUME (+/-) button on the remote control handset or TV set to make fine tuning adjustment. Press and hold the + button for higher VOLUME - VOLUME + frequency tuning, and press and hold the - for lower frequency tuning. Fine tuning data value will be automatically stored in [ Service Adjustment ] memory. It will return to normal TV mode if no opeation for 5 seconds. [ Exit from the Service Menu ] -17- Service Adjustments Service Adjustment-4 FOCUS ADJUSTMENT 1. Receive the monochrome circular pattern. 2. Set the brightness to normal and contrast FOCUS VR (Upper side) to maximum. 3. Adjust the focus control on the F.B.T. for the best focus on the screen centre. +B POWER SUPPLY CHECK 1. Connect a DC voltmeter to TP-B and the ground. TP-B 2. Set the brightness to normal and contrast to maximum. 3. Tune the receiver to an active channel and synchronized picture. 4. The +B voltage must be 140