Xoceco TK2016, TK2026 Schematic

COLOR TELEVISION

TK2016

(TK2026)

CONTENTS

Safety instruction………………………………………………………………………1 General instruction……………………………… ……………………………………… .1 Alignment instruction……………………………………………………………………2 Alignment flow ..……………………………………………………………………..2 Alignment method…………………………………………………………………..3

Block diagram......………………………………………………………………………...10

MAIN IC………… …………………………………………… ………………………..11 Schematic diagram………………………………………………………………….16

APPENDIX:Exploded view

Part list

Note: This service manual is only for professional service personnel’s reference. Before

servicing the unit, please read the following items carefully.

1 Safety instruction

1.1 X-RAY radiation precaution

1.1.1 Excessive voltage will cause harmful X-ray. To avoid this radiation hazard, the high voltage should

fall within the limitation. The appliance works at AC 120V, 60Hz. The high voltage of zero beam

current(brightness, contrast and color is min) should be within 27kV on condition that the main power

(B+) voltage is AC120V. And it should not exceed 28kV in any condition.

When servicing, please refer to the HIGH VOLTAGE CHECK procedure this service manual before

check the high voltage and the high voltage meter should be reliable and accurate.

* Keep the main power voltage at 120V when checking the high voltage.

1.1.2 The primary source of X-RAY RADIATION is the CRT. The CRT of this TV set have gotten the

approval of safety authentication inspection. The replacement CRT should be exactly the same type and

specification CRT which has gotten a similar safety approval, and check the high voltage according to

the HIGH VOLTAGE CHECK procedure.

1.2 safety precaution

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

transformer is necessary during dynamic service to avoid possible shock hazard.

b. Always discharge the graphite layer conductor when moving the CRT.

c. Disconnect the power cord before replacing parts.

d. When replacing high-power resistor, keep the resistor 10 mm away from the circuit board.

1.3 Component safety precaution

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

characteristics are often passed unnoticed by a visual inspection. Replacement parts which have these

special safety characteristics are identified in this manual and its supplement electrical components

having such features are shaded or marked by 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 characteristic as specified in the parts list may create

shock, fire, X-RAY RADIATION or other hazards.

2.General instruction

2.1 Copy the standard model data to let EEPROM (N702 24C08)of the chassis have those data before

placing it on the unit, do “factory adjustment” if necessary. If use a blank EEPROM directly, you should

preset IIC data and then do other common adjustment. Refer to TABLE1 to preset EEPROM.

2.2 the adjustment should be done under following circumstances without additional instruction

a) Alternating current 120V/60Hz

b) Preheat at least 30 min

2.3The unit has auto degaussing circuit, the auto degaussing process can be finished within 2s when the

main power. only when turn on the unit at least 20min after last time turn off TV does the auto

degaussing circuit work.

2.4 If the CRT with magnetism affects color purity and convergence, when the auto degaussing eraser. if

the color purity and convergence are still not very good, then corresponding adjustment should be done.

Refer to picture tube adjustment method for adjustment.

3 Alignment instruction

3.1 Debugging item

a)adjust mode instruction

b)B+ voltage adjustment

c)RFAGC voltage adjustment

d)focus adjustment

e)Screen-grid voltage white balance, sub brightness adjustment

f)filed scan center, line , amplitude adjustment

g)H-scan center adjustment

3.2 Alignment flow

E2PROM copy

High voltage check

B+ adjustment

RFAGC adjustment

Focus adjustment

Screen-grid voltage white

balance

Scan amplitude

center

X-ray protect check

Filament voltage check

AV check

Sub brightness check

White balance check

Color Purity, convergence check

AV, S terminal check

check

Fig-1 alignment flow

The unit and remote control

CCD function check

3.3 Enter/exit factory adjustment method

Use remote control, press “MENU” button, then press 6483,”TEST”will appear on screen to show that

you have entered the factory adjustment method, press “STANDBY” to exit it. Use factory remote control,

press the “PRESET” and “TEST” button, then the screen display “test” which means you have entered

into the factory adjustment mode, press the “TEST” or “STANDBY” to exit.

3.4 select adjustment item and adjust data

after entering factory adjustment mode, press 1-4 number buttons to select menu 1- menu 4; To enter

into MENU0, MENU5-MENU9, you may return to MENU1-MENU4 or just after you enter into “TEST”

interface, quickly press“CHILD LOCK” button and then the number button (0,5-9) to enter into relative

menus. Press “CH+” and “CH-” to select and “V+” and “V-”to adjust.

3.5 User purview

a).Factory adjustment mode menu1-menu4: only debugging worker, service checker, craftwork

technician, designer may operate.

b).Factory adjustment mode menu0, menu5-menu9: only craftwork technician, designer may operate.

4 Alignment method

4.1 B+ voltage adjustment

a) connect B+ point with a digital voltmeter to measure the negative pole of VD524

b) receive PHILIPS test pattern signal and set the picture to standard.

c) Adjust VR501 to let the value of B+ voltage be 110 V ±0.5 V (yongxin super pure flat)

4.2 AGC adjustment

a) receive VHF-H band,60 dB RF signal.

b) Select factory menu2 of “AGC”.

c) Adjust AGC-TOP to let the picture just without noisy, then the voltage of tuner AGC is the

required value for adjustment.

d) exit factory menu

4.3 Normal temperature aging

a) do not receive signals.

b) under ”Test” condition, set the accelerator to an appropriate point for aging.

4.4 Accelerator adjustment

a) do not receive signals;

b) select “SC” of factory menu3 to let the field scanning stop working.

c) adjust acceleration potentiometer to let bright lines just appears on screen.

d) exit SC menu.

4.5 High voltage check

Note: the main power voltage (B+=110 V)can affect the high voltage directly, so be sure to let the B+

power voltage accurate. Under any state, the high voltage should not exceed 28 kV.

a) connect an accurate high voltage meter between the second anode cap of picture tube and

ground.

b) turn on TV and receive testing card signal.

c) set picture to standard, the high voltage should be 25 kV± 0.5 kV. d) the high voltage should not exceed 27KV with minimum brightness and contrast.

4.6 Focus adjustment

a) receive A12-PHILIPS (NTSC)signal

b) adjust focus electrode potentiometer on FBT to optimize B area focus of screen.

4.7 White balance adjustment (color temperature 12000°K± 8MPCD,X=0.270± 0.008,Y=0.283± 0.008) a) receive full white signal, set color is 0

b) select factory menu3

c) on the basis of blue gun ”BD”, select and adjust “RD, GD” item to make white balance

respectively at brightness Y=6cd/m

, Y=80cd/m2 meet standard (color temperature 12000°K± 8MPCD,

x=0.270± 0.008, y=0.283± 0.008)

d)If at brightness Y=6cd/m

white balance can not meet standard, you may adjust “RB, GB”item,

then repeat step C) until white balance meet standard.

4.8 Filed scanning adjustment (fig-2)

a) Receive NTSC of A12-PHILIPS test pattern signal.

b) select factory menu1

c) adjust V-SLOPE menu to let the horizontal center line of test pattern above blanking.

d) select V-SHIFT menu and adjust to let the vertical center of picture coincide with

vertical center of picture tube.

e) Select V-SIZE menu and adjust to let the vertical reproduction ratio of picture acceptable 8%.

f) Adjust V.SC to optimise the vertical S correction of picture.

Horizontal line

Under part banking

Fig-2 field scan adjustment

4.9 Horizontal scanning adjustment (Fig-3)

a) Receive A12-PHILIPS(NTSC) signal

b) Select factory menu1

c) Select H.SHIFT menu and adjust to let the scanning horizontal center coincide with mechanical

center of picture tube

d) Exit factory menu

Fig-3 line scan adjustment

4.10 Sub-brightness adjustment

a) Receive A12-PHILIPS(NTSC) signal

b) Select “SB” of factory menu3

c) Adjust “SB” to let things between the sixth and seventh grey scale clear

4.11 OSD adjustment

a) Receive A12-PHILIPS(NTSC) signal

b) Select OSD H and OSD V of factory menu4. Adjust OSD H and OSD V to let OSD at a specified

place.

c) Exit factory menu

4.12. Checking point

4.12.1 High voltage check

1) Connect High Voltage meter between CRT second anode and GND.

2) Receive A7 signal, set the control to “STANDARD”, measure the high voltage value, the reading

should be 25 kV±0. 5 kV

3) Set the brightness and contrast to miminum (zero beam current), measure the high voltage, the

reading should not exceed 27kV.

4.12.2 CRT filament voltage check

Receive A7 signal, set user control to “STANDARD” mode, use effective voltage meter to measure CRT filament voltage, the reading should be (6.3±0.3) Vrms

4.12.3 X-ray protection check

1) Receive A7 signal, set user control to “STANDARD” mode.

2) Use voltameter to measure VD482 positive pole to GND voltage, the reading should be between 1.0

V~2.5 V.

3) Use 5.3V DC regulated voltage power with 1K resistor in series to touch TP1 (VD482 positive pole),

connect DC regulated voltage power negative pole to GND, X-Ray protection circuit should function,

at this time the TV set should be without raster, without sound. Disconnect the DC regulated voltage

power, picture and sound should restore to normal.

4.12.4 Picture and sound check

1) Receive standard TV signal.

2) Use picture control buttons to check color, contrast, brightness, sharpness, tint’s function.

3) Use sound control buttons to check volume control function.

4.12.5 Sub-brightness check

Receive A7 signal, set brightness to 75, contrast to 50, color to 0, sharpness to 50, picture left side 1-6

lattices slightly light up.

4.12.6 Color purity and convergence check (in normal way)

4.12.7 AV terminals IN/OUT check, S-VIDEO in check, Y,Cb,Cr in check.

4.12.8 Other buttons on the TV set and remote controller function check.

4.13 Degaussing

a) The unit has and auto degaussing circuit, the degaussing circuit works several seconds after turning

on TV

b) If you want to move TV or change the direction, turn off TV and ten minutes later the degaussing

circuit will work

c) For better degaussing effect, you can use magnetic eraser

d) Move the magnetic eraser clockwise before your TV, when it is 2m away from your TV, turn off the

magnetic eraser. If the effect is still not very good, you can adjust “color purity” and “convergence”

4.14 Color purity correction

a) Turn on your TV

b) At least 15 minutes later, use anti-magnetized coil for degaussing

c) Obtain maximum brightness and contrast

d) Select factory menu3 and adjust to let R and B be zero, then let only green raster appear on the

screen at the moment

e) Loosen screws of deflection yoke frame to let vertical green belt appear on screen only

f) Move the rubber wedge

g) Rotate along neck of picture tube and slide color-purity magnets until the green belt at the middle of

screen and is vertical at the same time

h) Slowly move the deflection yoke backward of forward until the whole green raster appears on screen,

tighten the screws of the deflection yoke

i) Check the color purity of red raster and blue raster

j) Adjust white balance again to obtain white raster

4.15 Convergence correction

4.15.1 Central convergence correction

a) Turn on your TV

b) At least 15 minutes later, receive square test pattern signal

c) Adjust brightness and contrast to get the best picture

d) Adjust the angle of two tetrode magnetic rings to let the red vertical line coincide with the blue

vertical line at middle of screen

e) Keep the angle unchanged, move the two tetrode magnetic rings at the same time to let the red and

blue horizontal lines coincide at middle of screen

f) Adjust two hexode magnetic rings to let the green line coincide with the mixed line of red and blue.

Adjust the angle between them will affect the vertical line, move them together will affect the

horizontal line.

g) Repeat d), e), f) and observe the movement of red, green and blue.

4.15.2 Ambient convergence correction

a) Turn on your TV

b) At least 15 minutes later, loosen the screws of the deflection yoke

c) Fixate the rubber wedge temporarily under the deflection yoke

d) Move the deflection yoke upward or downward to get best convergence, push the rubber wedge into

space between picture tube and deflection yoke to fixate the deflection yoke temporarily

e) Place the rubber wedge whose overlay paper has been removed at the bottom space

f) Move the deflection yoke left and right to get best convergence

g) Keep the condition unchanged, place another rubber wedge whose overlay paper has been

removed also at the upper space at the same time

h) Remove the interim rubber wedge, adhere it to picture tube and deflection yoke

i) After placing three rubber wedges, check all the convergence again

j) Stick three transparent viscous belts to the rubber wedge

4.16 Software adjustment instructions

4.16.1 instructions

This software contain MTS (option), English, Frence and Spanish of OSD, CCD and Parental Control

function, FS tuner mode, 181 channel.

4.16.2 turn on the unit in the STANDBY state

Press CH+/CH- buttons turn on in the STANDBY state.

4.16.3 Information of software version

Enter MEU9 of the factory menu in the top.

4.16.4 “STANDARD”, “COLORFUL” and “ SOFTNESS”

a).Enter MENU5 Mode of the factory menu

b).charge their for seemly analog quantity, then return standard option.

Chart 1 I

C standard UOC for export bus control adjustment i t em def ault setting

C TDA (NOM)8377-B-6NA E

PROM pre-set data

MI Items range Preset

M0 SUBCON 0-63 56(sub-contrast)

SUBCOL 0-63 56(sub-chroma)

SUBSHP 0-63 48(sub-acutance)

SUBTINT 0-63 31(sub-hue)

AKB ON/OFF ON

M1 V.SLOPE 0-63 36(field center adjustment)

V.SHIFT 0-63 32(field point adjustment)

V.SIZE 0-63 36(field amplitude adjustment)

V.SC 0-63 32(field line )

HSHIFT 0-63 32(line point adjustment)

PROGRAMA.NO 2(channel)

M2 AGCTAKEOVER 0-63 21(AGC adjustment)

SHIPPING 0(leave factory set)

M3 BT 0-100 75(adjust white balance of brightness)

CT 0-100 75(adjust white balance of brightness contrast)

SC 0

RB 0-63 32(red cut off level adjustment)

GB 0-63 32(green cut off level adjustment)

RD 0-63 32(red cut off level adjustment)

GD 0-63 32(green cut off level adjustment)

BD 0-63 32(blue cut off level adjustment)

SB 0-63 40(sub brightness adjustment)

M4 OSD.V.POSITION 0-63 15(OSD position)

OSD.H.POSITION 0-63 25(OSD H-position)

BTSC-MODE MONO/STEORO MONO(STEORO,SAP )

BTSC-ST 0-15 13

BTSC-SP 0-15 12

BTSC-L1 0-15 1

BTSC-A1 0-31 15

BTSC-A2 0-31 0

BTSC-TC 0-7 0

BTSC-STS 0-1

BTSC-ADJ

M5 MODE STANADARD(standard, soft, floweriness)

BRIGHT 0-100 75

COLOR 0-100 50

SCBRIGHT 0-63 23

YDELAYTV 0-15 12

YDELAYAV 0-15 12

M6 OSO 0-1 1(field over-scan switch)

AGCSPEED 0-3 1(AGC of speed)

FFI 0-1 0(IF PLL SPEED)

FMWS 0-1 1(frequency range of sound OFF=225KHZ,ON=450KHZ)

RP0 0-3 0(pre-shock and over-shock scale)

NTSCMATRIX USA/JAPAN USA

VOLPIN 0-1 0(1:push-pull output; 0: OC gate output.)

SOFT CLIP 0-3 3(white level limit)

PEAK WHITE 0-15 15(peak white limit)

CORING 0-1 0(coring noise reduction)

M7 AV2 0/1 1

SVHS 0/1 1

YUV 0/1 1

VOLADJPOING 1(volume value have:1,25,50,75)

VOLVALUE 20(volume curve value:20,60,75,90)

M8 CATHOOELEVEL 0-15 7(cathode level)

UOCVOLUME 0/1 0(0:PWM terminal control; 1:UOC sound amplitude

FMATT 0-63 45(UOC sound output of amplitude) BTSC : 38

COMBFILTRE 0-1 0(N comb filter)

HEADPHONE 0-1 0(earphone function selection)

VM OPTION 0/1 0(VM function selection)

FRANCE 0/1 1 French

SPANISH 0/1 1 Spaish

M9 NOM8377-B-6NA

STARTON 0-2 2(turn on)

CONTRAST

0-100 75

control of inside)

STARTTIME 6-15 8(turn on time)

IF OFFSET 0-63 32(IF compensate)

TUNER OPTION 0-2 0(BXATB011F---X/ BXATB108F---K) 1 (BXATB017F---K)

2(XXX)

GAME 0/1 0

GALENDA 0/1 0

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