Xoceco TS2019, M2019 Schematic

COLOR TELEVISION

TS2019

(M2019)

CONTENTS

X-RAY RADIATION PRECAUTION………………………………………………………1

SAFETY PRECAUTION…………………………………………………………………..1

PRODUCT SAFETY NOTICE…………………………………………………………….2

INSTALLATION AND SERVICE ADJUSTMENTS………………………………………3

GENERAL INSTRUCTION…………………………………………………………………3

ALIGNMENT ITEMS AND PROCEDURE………………………………………………..3

FACTORY ADJUSTMENT MODE…………………………………………………………4

CHECKING POINT……………………………………………………………………………5

PRESET THE FOLLOWING IN FACTORY…………………………………………………6

FACTORY MENU………………………………………………………………………………6

CONVERGENCE MAGNET ASSEMBLY POSITIONING……………………………..8

COLOR PURITY ADJUSTMENT…………………………………………………………..8

CONVERGENCE ADJUSTMENT…………………………….……………………………..8

CENTER CONVERGENCE ADJUSTMENT …………………………………………..8

CIRCUMFERENCE CONVERGENCE ADJUSTMENT ……………………………..9

USA CHANNEL FREQUENCY TABLE (181 CH)……………………………………… 9

WIRING DIAGRAM……………………………………………………………………….11

BLOCK DIAGRAM………………………………………………………………………...12

IC BLOCK DIAGRAM……………………………………………………………………..13

PART LIST …………………………………………………………………......................18

SCHEMATIC DIAGRAM………………………………………………………………..........38

CAUTION: THIS SERVICE MANUAL IS ONLY FOR PROFESSIONAL SERVICE PERSONNEL’S

REFERENCE. BEFORE SERVICING THIS CHASSIS, PLEASE READ THE

FOLLOWING NOTICE ITEMS.

SAFETY INSTRUCTION

Before servicing and aligning this equipment, please read the following “X-RAY RADIATION

PRECAUTION” ,“SAFETY PRECAUTION” and “PRODUCT SAFETY NOTICE”.

X-RAY RADIATION PRECAUTION

1. Excessive high voltage can produce potentially hazardous X-RAY RADIATION. To avoid such

hazards, the high voltage must not be above the specified limit. The normal value of the high voltage

of this receiver is 26.5kV(20”) at zero beam current (minimum brightness) under 220V AC power

source. the high voltage must not, under any circumstances, exceed 26.5kV.

2. Each time a receiver requires servicing, the high voltage should be checked following the HIGH

VOLTAGE CHECK procedure in this manual. It is recommended the reading of the high voltage be

recorded as a part of service record. It is important to use an accurate and reliable high voltage meter.

3. This receiver is equipped with a Fail Safe (FS) circuit which prevents the receiver from producing an

excessively high voltage even if the B+ voltage increases abnormally. Each time the receiver is

serviced, the FS circuit must be checked to determine that the circuit is properly functioning,

following the FS CIRCUIT CHECK procedure in this manual.

4. The primary source of X-RAY RADIATION in this TV receiver is the picture tube. For continuous

X-RAY RADIATION protection, the replacement tube must be exactly the same type tube as specified

in the parts list.

5. Some parts in this receiver have special safety-related characteristics for X-RAY RADIATION

protection. For continuous safety, parts replacement should be undertaken only after referring to the

PRODUCT SAFETY NOTICE below.

SAFETY PRECAUTION

WARNING:

Service should not be attempted by anyone unfamiliar with the necessary precaution on this receiver. The

following are the necessary precautions to be observed before servicing this chassis.

1) Since the power supply circuit of this receiver is directly connected to the AC power line, an isolation

transformer should be used during any dynamic service to avoid possible shock hazard.

2) Always discharge the picture tube anode to the CRT conductive coating before handling the picture tube.

The picture tube is highly evacuated and if broken, glass fragments will be violently expelled. Use shatter

proof goggles and keep picture tube away from the unprotected body while handling.

3) When replacing a chassis in the cabinet, always be certain that all the protective devices are put back in

place, such as: non-metallic control knobs, insulating covers, shields, isolation resistor-capacitor network

etc.

4) When replacing parts or circuit boards, disconnect the power cord.

5) When replacing a high wattage resistor (oxiode metal film resistor) on the circuit board, keep the resistor

10mm (1/2in) away from circuit board.

6) Connection wires must be kept away from components with high voltage or high temperature.

7) If any fuse in this TV receiver is blown, replace it with the FUSE specified in the chassis parts list.

8) Before returning the set to your customer, always perform an AC leakage current check on the exposed

metallic parts of the cabinet, such as antennas, terminals, screwheads, metal overlays, control shafts etc. to

be sure the set is safe to operate without danger of electrical shock. Plug the AC line cord directly into a

220V AC outlet (do not use a line isolation transformer during this check). Use an AC voltmeter having

5000 ohms per volt or more sensitivity in the following manner:

Connect a 1500 ohm 10 watt resistor, paralleled by a 0.15µF, AC type capacitor, between a known good

earth ground (water pipe, conduit, etc.) and the exposed metallic parts, one at a time. Measure the AC

voltage across the combination of 1500 ohm resistor and 0. 15µF capacitor. Reverse the AC plug at the AC

outlet and repeat AC voltage measurements for each exposed metallic part. Voltage measured must not

exceed 0.3 volts RMS. This corresponds to o.2 milliamp. AC. Any value exceeding this limit constitutes a

potential shock hazard and must be corrected immediately.

C VOLTMETER

0.15 FD

Good earth ground such as a water pipe, conduit, etc.

1500ohm 10watt

Place this probe on each exposed metallic part.

PRODUCT SAFETY NOTICE

Many electrical and mechanical parts in the chassis have special safety-related characteristics. These

characteristics are often passed unnoticed by a visual inspection and the X-RAY RADIATION protection

afforded by them cannot necessarily be obtained by using replacement components rated for higher wattage,

etc. Replacement parts which have these special safety characteristics are identified in this manual and its

supplement electrical components having such features are shaded on the schematic diagram and the parts list.

Before replacing any of these components, read the parts list in this manual carefully. The use of substitute

replacement parts which do not have the same characteristics as specified in the parts list may create shock,

fire, X-RAY RADIATION or other hazards.

B+ CHECK

1) Prepare the test equipment.

2) Use the DC voltameter at DC 370V position to test B+ test point, i.e. B+.

3) Connect the power plug to AC 220V/50Hz, turn on the power switch, wait for normal raster, Check B+ =

110V±0.2V.

Test point B+ B1-5V B2-8V B3-10V B4-32V TH-12V TH-20V TH-200V

DC(V) 110 5 8 12 32 12 20(22) 200

INSTALLATION AND SERVICE ADJUSTMENTS

GENERAL

In the majority of cases, a color television receiver will need only slight touch – up adjustment upon installation. Check the basic characteristics such as FS,EHV,and focus. Observe the picture for good black and white details without objectionable color shading. If color shading is evident, demagnetize the receiver. If color shading still persists, perform purity and convergence adjustments. This should be all that is necessary to achieve optimum receiver perfomance.

FOCUS ADJUSTMENT

Adjust the FOCUS control (on T301) for well defined scanning lines on the picture screen.

HIGH VOLTAGE CHECK

CAUTION: These is no HIGH VOLTAGE ADJUSTMENT on this chassis. Checking should be done following the steps below.

1. Connect an accurate high voltage meter to the second anode of the picture tube.

2. Turn on the receiver. Set the BRIGHTNESS and CONTRAST controls to minimum (zero beam current).

3. High voltage will be measured below 26.5(20”)KV.

4. Vary the BRIGHINESS control to both extremes to be sure the high voltage does not exceed the limit under any conditions.

General instruction

1. This chassis’ EEPROM'(N801 M24C08) should copy standard data, if necessary, deal it with “factory

adjustment”. If directly use blank EEPROM, should first preset I

alignment. For factory adjustment method, refer to The appendix: factory menu.

2. If without special indication, the alignment is conducted on the below condition:

a) AC power supply 220 V/50 Hz.

b) The whole unit is preheated for more than 30 min.

3. There is built-in auto degaussing circuit, it will degauss automatically within 1second after turning on.

4. If CRT is with magnetism and affects color purity and convergence, the internal degaussing can not degauss

completely, can use degaussor to degauss externally. If color purity and convergence is still poor, then

do color purity and convergence adjustment.

C data, then go on other common

Alignment items and procedure

1. B+ voltage check

2. RF AGC voltage adjustment

3. Focus adjustment

4. Screen-grid voltage and white balance adjustment

5. Horizontal,vertical scan center adjustment

6. Horizontal,vertical scan amplitude adjustment

7. Pattern correction adjustment

8. The alignment flow chart see figure below.

EEPROM copy

B+ check

High voltage check

X-ray protection check

RFAGC adjustment

Filament voltage check

FOCUS

Picture and sound check

Sub-brightness check

Screen-grid voltage White balance adjustment

White balance check

Scanning amplitude center & raster correction adjustment

Color purity convergence check

、

Check

AV terminal check

Figure 1: Alignment flow chart

The TV set & remote

controller's function check

Factory adjustment mode

1. B+ voltage test

a) Make sure the AC power is 220 V/50 Hz

b) Connect digital voltmeter to B+ test point, receive A-7 signal, set picture control to“DYNAMIC”

state, test B+, the test voltage should be 100 V±0.5 V (21” PF), or 110V±0.5 V (14” PF AND 21”),

or 140V (25”).

2. AGC adjustment

a) Receive 60 dB split field A-7 signal.

b) Use oscilloscope or digital voltmeter to monitor test N201 pin 43 voltage (AGC output). c) enter factory menu, select RF DELAY ADJ, by making use of [←][→] button, increase the value from low

to high until the voltage just reach 4.0 V, at this time picture noisy spot should basically disappear, otherwise continue fine tune RF DELAY ADJ

3. Focus adjustment

3. 1 Receive A-12 signal, set user control to “DYNAMIC” state.

3. 2 Adjust FBT’s focus potentiometer, to make the screen’s B area’s focus optimum.

4. Acelerating electrode adjustment method (use A-7 signal)

4.1 Roughly adjust white balance, fix GCUT value, adjust RCUT, BCUT, RDRV, BDRV ’s value to make

white balance basically normal.

4.2 Set the color to 0, contrast to 10, use oscilloscope to adjust CRT’s red gun’s waveform (see below figure),

adjust brightness to make the seventh step’s (the darkest) DC level be 180V, adjust accelerating electrode

to make the seventh step slightly light up (just can separate the seventh step and below dark field).

4.3 Fine adjust white balance (color temperature: 12000K±8MPCD X=0.270±0.008 Y=0.283±0.008 )

4.4 Set contrast,brightness,color all to 0, adjust BRTN to make A-7’s upper left 2 lattice slightly light up.

5. Horizontal, vertical scan center adjustment

NTSC(60Hz)H-center,V-center adjustment Receive G23 signal, set user control to “DYNAMIC” state, adjust V-center V-position， H-PHASE to

make picture’s center be in accordance with screen’s center.

6. Vertical scan amplitude adjustment

NTSC(60 Hz)V-amplitude adjustment Receive D35 signal, set user control to “DYNAMIC” state, adjust V-amplitude V-SIZE to make picture’s

upper and lower over scanning be screen size’s 8%.

Fig 2: red gun waveform

180V

Checking point

1. High voltage check

1.1 Connect high voltage meter to CRT’s second anode and GND.

1.2 Receive D-8 signal, set user control to “DYNAMIC” state, the high voltage should be 29.0 kV±1 kV

(21” PF and 25”) or 25.0kV±1kV (14” PF) or 26.5kV±1kV (21”).

1.3 When brightness and contrast be set to minimum (zero beam current), the high voltage should not exceed

32 kV.

2. CRT filament voltage check

Receive D-8 signal, set picture control to “DYNAMIC” state, use effective value voltmeter to test CRT filament voltage, the reading should be (6.3±0.3)Vrms.

3. X-ray protection check

3.1 Receive D-8 signal, set user control to “DYNAMIC” state.

3.2 Short R305(TP301,TP302),X-ray protection circuit should effect.

4. Picture and sound check

4.1 Receive standard TV signal.

4.2 Making use of picture control buttons to check color,contrast,brightness,sharpness,tint’s control function.

4.3 Making use of sound control buttons to check volume control function.

5. Sub-brightness check

Receive D-8 signal, set color ,contrast,brightness all to 0, picture’s left side first grid slightly lights.

6. Color purity and convergence check(Use common regulation)

7. AV terminals ( AV IN/OUT check)

8. Other control buttons (on the set and on the remote controller) function check.

Preset the following in factory

1. Picture menu:

BRIGHTNESS 30

COLOR 30

SHARPNESS 30 TINT ±00

PICTURE

▼MORE

2. Volume preset to 30.

3. Set OSD language to English.

4. TV mode: channel position number CABLE 3.

CONTRAST 60

PERSONAL

MODE

Factory menu

1. Enter into factory menu to operate.

1.1 Press factory button ,enter into factory menu.

1.2 Use CH+/CH- button to select the menu, use VOL+/VOL- button to enter the function menu.

1.3 In factory menu status, press MENU button to exit.

2. Factory menu contents

Appendix 1 FACTORY MENU

FACTORY MENU

1:VDJ ADJ

1. VIF VCO AUTO ADJ OFF VIF VCO auto adjustment

2. RF DELAY ADJ TUNER AGC adjustment

3. S-TRAP ADJ S-TRAP auto adjustment

2: RASTER ADJ

1. V-POSITION

Vertical position adjustment（PAL）

2. V-SIZE Vertical size adjustment

3. H-POSITION Horizontal position adjustment

4. WHITE BACK

5. VS-CORRECTION Vertical S-adjustment

6. V-LINEARITY Vertical linear adjustment

7. H-POSITION（N）

8. V-SIZE（N）

9. V-SHIFT（N）

10. VS-CORRECTION（N）

11. V-LINEARITY（N）

Horizontal position adjustment

Vertical size adjustment

Vertical position adjustment

Vertical S-adjustment

Vertical linear adjustment

3: CRT ADJ

1. CUT OFF-R TV white balance adjustment

2. CUT OFF-G

3. CUT OFF-B

4. DRIVE R

5. DRIVE B

6. YUV）CUT OFF-R

7. YUV）CUT OFF-G 8．（YUV）CUT OFF-B

9. YUV）DRIVE-R

10.（YUV）DRIVE-B

YUV white balance adjustment

4: PICTURE ADJ

1. SUB BRIGHTNESS Sub-brightness adjustment

2. SUB CONTRAST Sub-contrast adjustment

5: USER MENU RESET OFF User menu presetting

6: SERVICE MENU

1. H VCO ADJ Horizontal VCO auto adjustment

2. TRAP FINE ADJ Color trap fine adjustment

3. SUB TINT TV sub tint

4. SUB TINT AV AV sub tint

5. SUB TINT YUV YUV sub tint

6. SUB COLOR Color adjustment

7. C ANGLE95

8. TAKE OFF Color BPF/TAKE OFF on/off

9. OSD LEVEL OSD level on/off

10. Y-DL Brightness delaying time

11. Y-DL SECAM

12. SECAM KILLER

13. SECAM BGP

14. VIDEO OUTGAIN Demodulation output range adjustment

15. OM DET Over modified detecting on/off

16. S-SLICE DOWN Sync detecting slice stage

17. AUTO SLICE DN Auto detecting on/off

18. V SYNC DET Vertical sync detecting

19. V-1 WINDOW

20. AFC1 GAIN UP H AFC1gain

21. AFC2 GAIN DOWNN H AFC2 gain

22. ABCL Brightness/contrast auto control

23. ABCL GAIN Brightness/contrast auto control gain

24. GAMMA

25. BLACK ST OFF Black level delay on/off

26. BLACK ST ADJ

27. BLACK ST GAIN

28. VIF FREQ VIF selecting

29. VDL ADJ

30. UDL ADJ

31. IC SELECTION

32. OP PAL-M/N

33. OP AV-SUSTEM AV mode

34. AUDIO ATT Volume output control

35. MONITORING

36. EEPROM OPTION EEPROM selecting

37. POW-ON SEARCH Power-on search selecting

38. OSD H-POSITION OSD horizontal position adjustment

39. EEP ADJ EEPROM modifying

40. PIC-DYNAMIC Dynamic scalar selecting

41. PIC-STANDARD Standard scalar selecting

42. PIC-SOFT Soft scalar selecting

CONVERGENCE MAGNET ASSEMBLY POSITIONING

Convergence magnet assembly and rubber wedges need mechanical positioning. Refer to below figure 1.

COLOR PURITY ADJUSTMENT

NOTE: Before attempting any purity adjustment, the receiver should be operated for at least fifteen minutes.

1. Demagnetize the picture tube and cabinet using a degaussing coil.

2. Set the CONTRAST and BRIGHTNESS controls to the maximum.

3. Receive PM5515 monochromatic signal (such as G) to provide a green raster on the screen.

4. Loosen the clamp screw holding the yoke, and slide the yoke backward to provide vertical green belt

(zone) in the picture screen.

5. Remove the Rubber Wedges.

6. Rotate and spread the tabs of the purity magnet around the neck of the picture tube until the green

belt is in the center of the screen. At the same time, center the raster vertically by adjusting the

magnet.

7. Move the yoke slowly forward or backward until a uniform green screen is obtained. Tighten the

clamp screw of the yoke temporarily.

8. Check the purity of the red and blue raster.

9. Obtain a white raster, referring to “CRT WHITE BALANCE ADJUSTMENT”.

10. Proceed with convergence adjustment.

FIG.3

CONVERGENCE ADJUSTMENT

NOTE: Before attempting any convergence adjustments, the receiver should be operated for at least fifteen

minutes.

CENTER CONVERGENCE ADJUSTMENT

1. Receive crosshatch pattern with a color bar signal generator.

2. Adjust the BRIGHTNESS and CONTRAST controls for well defined pattern.

3. Adjust two tabs of the 4-Pole Magnets to change the angle between them (see figure 4) and superimpose red

and blue vertical lines in the center area of the picture screen. (see figure 5)

4. Turn the both tabs at the same time keeping the constant angle to superimpose red and blue horizontal lines

at the center of the screen.(see figure 5)

5. Adjust two tabs of 6-Pole Magnets to superimpose red/blue line with green one. Adjusting the angle affects

the vertical lines and rotating both magnets affects the horizontal lines.

6. Repeat adjustments 3,4,5, keeping in mind red, green and blue movement, because 4-Pole Magnets and

6-Pole Magnets interact and make dot movement complex.

CIRCUMFERENCE CONVERGENCE ADJUSTMENT

1. Loosen the clamping screw of deflection yoke to allow the yoke to tilt.

2. Put a wedge as shown in figure 1 temporarily. (Do not remove cover paper on adhesive part of the wedge.)

3.Tilt front of the deflection yoke up or down to obtain better convergence in circumference. (See figure 5).

Push the mounted wedge into the space between the picture tube and the yoke to hold the yoke temporarily.

4. Put other wedge into bottom space and remove cover paper to stick.

5. Tilt front of the yoke right or left to obtain better convergence in circumference (see figure 5)

6. Keep the yoke position and put another wedge in either upper space. Remove cover paper and stick the

wedge on the picture tube to fix the yoke.

7. Detach the temporarily mounted wedge and put it in another upper space. Stick it on the picture tube to fix

the yoke.

8. After fixing three wedges, recheck overall convergence. Tighten the screw firmly to fix the yoke tightly in

place.

9. Stick three adhesive tapes on wedges as shown in figure 3.

Fig5. Dot Movement Pattern

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