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Alignment and Adjustments

4. Alignment and Adjustments
4-1 Preadjustment
4-1-1 Factory Mode
1. Do not attempt these adjustments in the Video Mode. 2. The Factory Mode adjustments are necessary when either the EEPROM (IC902) or the CRT is replaced. 3. Do not tamper with the "Adjustment" screen of the Factory Mode menu. This screen is intended only for factory use.

4-1-3 When CRT Is Replaced
1. Make the following adjustments AFTER setting up after setting up purity and convergence : White Balance Sub-Brightness, Sub-Contrast Vertical Center Vertical Size Horizontal Size Fail Safe (This adjustment must be the last step).

4-1-2 When EEPROM (IC902) Is Replaced
1. When IC902 is replaced all adjustment data revert to initial values. It is necessary to re-program this data. 2. After IC902 is replaced, warm up the TV for 10 seconds.

4-2 Factory/Service Mode
4. Selection sequences for the PAL system:

4-2-1 Procedure for the "Adjustment" Mode
1. This mode uses the standard remote control. The Service Mode is activated by entering the following remote-control sequence : (1) STAND-BY DISPLAY MENU MUTE POWER ON. 2. The "SERVICE (FACTORY)" message will be displayed. The Service Mode has three components: Adjustment, Option and Reset. 3. Access the Adjustment Mode by pressing the "VOLUME" keys ( Up or Down). The adjustment parameters are listed in the accompanying table, and selected by pressing the CHANNEL keys (v ,w).

DOWN or UP key: AGCVCOSBTSCTSCRSCRG BGCDLSTTLCOVOLPSLPVS PVAPHSPEWPEPPECPETVSC TSCSAQEWPCTPTTPHMPVP PHPNSRPDLAGC. 5. The VOLUME keys increase or decrease the adjustment values (stored in the non-volatile memory) when Adjustment Mode is cancelled. 6. Cancel the Adjustment Mode by re-pressing the "HIDDEN" or "Power OFF/ON" keys. 7. After adjustments are completed, re-start the TV set.

4-1

Alignment and Adjustments

4-2-2 Main Adjustment Parameters

OSD AGC VCO SBT SCT SCR SC RG BG CDL STT LCO VOL PSL PVS PVA PHS PEW PEP PEC PET VSC TSC SA QEW PCT PTT PHM PVP PHP NSR PDL AUTO GAIN CONTROL

FUNCTION VOLTAGE CONTROLLED OSCILLATOR SUB BRIGHTNESS SUB CONTRAST SUB COLOUR S-CORRECTION RED DRIVE GAIN BLUE DRIVE GAIN CATHODE DRIVE LEVEL SUB TINT ( FOR NTSC ) SECAM-L VOLTAGE CONTROLLED OSCILLATOR VOLUME INITIAL LEVEL PAL VERTICAL SLOPE PAL VERTICAL SHIFT PAL VERTICAL AMPLITUDE PAL HORIZONTAL SHIFT PAL E-W WIDTH PAL E-W PALABOLA PAL E-W CORNER PAL E-W TRAPEZIUM VERTICAL SCROLL TELETEXT SUB CONTRAST SEPARATION ADJUSTMENT (STEREO) Q(12.8:9) MODEL E-W WIDTH PIP CONTRAST PIP TINT PIP HORIZONTAL MOVE PIP VERTICAL POSITION PIP HORIZONTAL POSITION NTSC SUB COLOUR PAL DELAYTIME

RANGE 0 - 63 0 - 127 0 - 23 0 - 23 0 - 23 0 - 63 0 - 63 0 - 63 0-7 0-7 0-1 0 - 63 0 - 63 0 - 63 0 - 63 0 - 63 0 - 63 0 - 63 0 - 63 0 - 63 0 - 63 0 - 63 0 - 15 0-7 0 - 15 0 - 63 0 - 15 0 - 63 0 - 63 0 - 23 0 - 15

4-2

Alignment and Adjustments

FACTORY MODE VALUE

OSD 2 (CH) AGC VCO SBT SCT SCR SC RG BG CDL STT 10

INITIAL LCO VOL PSL PVS PVA PHS 80(FIXED) 7 16 5(FIXED) 11(FIXED) 31 31 5 10(FIXED)

OSD 25

INITIAL 1 (FIXED) 31(FIXED) 31 31 40 38 22 22 30 31(FIXED) TSC SA

OSD 7 5

INITIAL 20(FIXED)

QEW PCT PTT PHM PVP PHP NSR PDL

7(FIXED) 31(FIXED) 8(FIXED) 31(FIXED) 31(FIXED) 3 (FIXED) 0 (FIXED)

PEW PEP PEC PET VSC

4-2-3 AGING Mode (Reference Only)
This pattern is used for pre-heating the CRT during manufacturing--it is accessed in the factory by twice pressing the "FACTORY " key. Even if the TV power is cut off, the Aging Mode is not cancelled, The AGING mode is cancelled by repressing the "HIDDEN" or any key on the front pannel.

4-3

Alignment and Adjustments

4-2-4 Option Byte Table
Option Byte 1.ZOOM MODE : NORMAL/ZOOM/16:9 2.AUDIO MODE : NICAM STEREO 3.ONE CHIP : TDA8844 4.LED OPTION : NORMAL 5.LANGUAGE : WEST ENG/GER/FRA/DUT/SPA/ITA/SWE 6.SYSTEM: CX 7.ATS OPTION : ON 8.FIELD POL : FIELD POS OPTION OSD PLU/NOR/ZOOM/16:9 ZOOM MODE NORMAL/ZOOM/16:9 NORMAL/ZOOM PLUS/NORMAL NICAM STEREO STEREO AUDIO MODE LINE STEREO MONO ONECHIP LED OPTION TDA8844 TDA8842 NORMAL POLAND WEST ENG/GER/FRA/DUT/SPA/ ITA/SWE EAST ENG/CZE/CRO/RUM/HUN/ POL CF CI SYSTEM CK CX CB ATS OPTION FIELD POL ON OFF FIELD POS FIELD NEG 12.8 : 9 CRT USED(26") NICAM MODULE USED A2 MODULE USED MONO MODULE USED (LINE STEREO MODEL ) MONO MODULE USED (MONO MODEL ) CRT(MORE THAN 22-INCH)USED CRT(MORE THAN 21-INCH)USED DEFAULT POLAND MODEL ONLY WEST EUROPE MARKET ENGLISH/GERMANY/FRANCE/ NETHERLANDS/SPAIN/ITALY/SWEDEN EAST EUROPE MARKET ENGLISH/CZECH/CROATIA/ROMANIA/ HUNGARY/POLAND SECAM-L/L', PAL/SECAM-B/G PAL - I ( UHF BAND ONLY) PAL/SECAM - B/G,D/K PAL/SECAM -B/G PAL -B/G ATM FUNCTION USED ATM FUNCTION NOT USED PHILIPS CRT USED OTHER CRT USED NOTE 12.8 : 9 CRT USED(30",22") NORMAL CRT USED

LANGUAGE

4-4

Alignment and Adjustments

Alignment and Adjustments

4-2-5 RESET
The Reset Mode is used during factory inspection. Function Reset: 1. 2. 3. Channels Language Station name Add/Erase Last condition Clear

4-3 Other Adjustments
4-3-1 General
1. Usually, a color TV needs only slight touchup adjustment upon installation. Check the basic characteristics such as height, horizontal and vertical sync and focus. 2. The picture should have good black and white details. There should be no objectionable color shading; if color shading is present, perform the purity and convergence adjustments described below. 3. Use the specified test equipment or its equivalent. 4. Correct impedance matching is essential. 5. Avoid overload. Excessive signal from a sweep generator might overload the front-end of the TV. When inserting signal markers, do not allow the marker generator to distort test results. 6. Connect the TV only to an AC power source with voltage and frequency as specified on the backcover nameplate. 7. Do not attempt to connect or disconnect any wires while the TV is turned on. Make sure that the power cord is disconnected before replacing any parts. 8. To protect against shock hazard, use an isolation transformer.

4-3-2 Automatic Degaussing
A degaussing coil is mounted around the picture tube, so that external degaussing after moving the TV should be unnecessary. But the receiver must be properly degaussed upon installation. The degaussing coil operates for about 1 second after the power is switched ON. If the set has been moved or turned in a different direction, disconnect its AC power for at least 30 minutes. If the chassis or parts of the cabinet become magnetized, poor color purity will result. If this happens, use an external degaussing coil. Slowly move the degaussing coil around the faceplate of the picture tube and the sides and front of the receiver. Slowly withdraw the coil to a distance of about 6 feet before removing power.

4-5

Alignment and Adjustments

Alignment and Adjustments

4-3-3 High Voltage Check
CAUTION: There is no high voltage adjustment on this chassis. The B+ power supply must be set to +155 volts (Full color bar input and normal picture level).

4-3-6 Purity Adjustment
1. Warm up the receiver for at least 20 minutes. 2. Plug in the CRT deflection yoke and tighten the clamp screw. 3. Plug the convergence yoke into the CRT and set in as shown in Fig. 4-2. 4. Input a black and white signal. 5. Fully demagnetize the receiver by applying an external degaussing coil. 6. Turn the CONTRAST and BRIGHTNESS controls to maximum. 7. Loosen the clamp screw holding the yoke. Slide the yoke backward or forward to provide vertical green belt. (Fig. 4-3). 8. Tighten the convergence yoke. 9. Slowly move the deflection yoke forward, and adjust for the best overall green screen. 10. Temporarily tighten the deflection yoke. 11. Produce blue and red rasters by adjusting the low-light controls. Check for good purity in each field. 12. Tighten the deflection yoke.

1. Connect a digital voltmeter to the second anode of the picture tube. 2. Turn on the TV. Set the Brightness and Contrast controls to minimum (zero beam current). 3. The high voltage should not exceed 33KV. 4. Adjust the Brightness and contrast controls to both extremes. Ensure that the high voltage does not exceed 33KV under any conditions.

4-3-4 FOCUS Adjustment
1. Input a black and white signal. 2. Adjust the tuning control for the clearest picture. 3. Adjust the FOCUS control for well defined scanning lines in the center area of the screen.

4-3-5 Screen Adjustment
1. Connect CRT socket pin GK, BK, RK to an oscilloscope probe. 2. Input a gray scale pattern. (Use a pattern generator, PM5518) 3. Use the Picture mode for the STANDARD picture. 4. Adjust the Screen VR (on the FBT) so that the _ voltage on the oscilloscope becomes 140+2.5V (See Fig. 4-1).

+ 140 _ 2.5V

GND Fig. 4-1 4-6

Alignment and Adjustments

Alignment and Adjustments

4 Pole Magnet 6 Pole Magnet Clamper Screw 2 Pole Magnet

2 POLE PURITY

YOKE CLAMP SCREW 6 POLE CONVERGENCE 4 POLE CONVERGENCE

Fig. 4-2 Convergence Magnet Assembly

Vertical Green Belt

31m/m

Fig. 4-3 Center Convergence Adjustment

4-3-7 White Balance Adjustment
(a) Set up 1. Warm up the TV for at least 30 minutes in the White Pattern. 2. Input a Toshiba pattern. (b) High-Light Adjustment 2 Set SCT to 40 ± 5 fL in the Factory Service Mode with using CA100. (See Fig. 4-4 x) (c) Low-Light Adjustment Fig. 4-4 Set SBT to 1.5 ± 0.2 fL in the Factory Service Mode with using CA100. (See Fig. 4-4 )

1

4-7

Alignment and Adjustments

Alignment and Adjustments

4-3-8 Center Convergence Adjustment
1. Warm up the receiver for at least 20 minutes. 2. Adjust the two tabs of the 4 pole magnets to change the angle between them. Superimpose the red and blue vertical lines in the center area of the screen. 3. Adjust the Brightness and Contrast controls for a well defined picture. 4. Adjust the two-tab pairs of the 4 pole magnets, and change the angle between them. Superimpose the red and the blue vertical lines in the center area of the screen. 5. Turn the both tabs at the same time, keeping the angle constant, and superimpose the red and blue horizontal line in the center of the screen. 6. Adjust the two-tab pairs of the 6-pole magnets to superimpose the red and blue line onto the green. (Changing the angle affects the vertical lines, and rotating both magnets affects the horizontal lines.) 7. Repeat adjustments 2~6, if necessary. 8. Since the 4-pole magnets and 6-pole magnets interact, the dot movement is complex (Fig. 4-5).

BLUE

RED

RED/BLUE

GREEN

BLUE RED

RED/BLUE GREEN

4-Pole Magnet Movement

6-Pole Magnet Movement

Fig. 4-5 Center Convergence Adjustment

4-3-9 RF AGC Adjustment
1. Tune to the strongest local station. 2. Enter the Factory Service Mode to make adjustments. 3. Adjust the AGC control untill noise(snow) disappears from the screen.

4-8

Alignment and Adjustments

Alignment and Adjustments

4-3-10 Geometry Adjustment
1. Input a lion head pattern. 2. Adjus t PVS s o that the pic ture is vertically centered. 3. Adjus t with PVA s o that the top and bottom margins of the pic ture are 4. 4. Adjus t PHS s o that the pic ture is horizontally centered. 5. Adjus t with PEW s o that the left and right margins of the picture are 5. 4

5

5 4

6. Input a crosshatch pattern. 7. Adjus t PEP, PEC , PET for vertical linearity.

4-9