Advent Q2016A Service Manual

SERVICE SERVICE

MANUALMANUAL

CONTENTS

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

…………………………………………………………………..

1 PRODUCT SAFETY NOTICE…………………………………………………………….2 INSTALLATION AND SERVICE ADJUSTMENTS………………………………………3 GENERAL INSTRUCTION…………………………………………………………………4 ALIGNMENT ITEMS AND PROCEDURE

………………………………………………..

4 FACTORY ADJUSTMENT MODE…………………………………………………………5 CHECKING POINT……………………………………………………………………………6 PRESET THE FOLLOWING IN FACTORY…………………………………………………7 FACTORY MENU

………………………………………………………………………………

CONVERGENCE MAGNET ASSEMBLY POSITIONING

……………………………..

11 COLOR PURITY ADJUSTMENT…………………………………………………………..11 CONVERGENCE ADJUSTMENT…………………………….……………………………..12 CENTER CONVERGENCE ADJUSTMENT …………………………………………..12 CIRCUMFERENCE CONVERGENCE ADJUSTMENT

……………………………..

12 USA CHANNEL FREQUENCY TABLE (181 CH)………………………………………14 WIRING DIAGRAM……………………………………………………………………….16 BLOCK DIAGRAM………………………………………………………………………...17 IC BLOCK DIAGRAM

……………………………………………………………………..

18 SCHEMATIC DIAGRAM………………………………………………………………….26 ELECTRICAL PARTS LIST………………………………………………………………27

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

29 or 26.5kV(20”) at zero beam current (minimum brightness) under 120V AC power source. the high voltage

must not, under any circumstances, exceed 32kV.

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

WA RN I N G:

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

120V 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

¦Ì

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 200V position to test B+ test point, i.e. B+.

3) Connect the power plug to AC 120V/60Hz, turn on the power switch, wait for normal raster, Check B

100V±0.2V.

Test point B+ B1-5V B2-9V B3-10V B4-32V TH-12V TH-20V TH-200V

DC(V) 100 5 9 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 T302) 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 9 (20”)KV.

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

FS CIRCUIT CHECK

The Fail Safe (FS) circuit check is indispensable for the final check in the servicing. Checking should be done following the steps below.

1. Turn the power switch on and adjust customer controls for normal operation.

2. Temporarily short TP501 and TP502 on the Main Board with a jumper wire. Raster and sound will disappear.

3. The receiver must remain in this state even after removing the jumper wire. This is the evidence that the FS circuit is functioning properly.

4. To obtain a picture again, temporarily turn the receiver off and allow the FS circuit more than 30 seconds to reset. Then turn the power switch on to produce a normal picture.

Troubleshooting Guide for Fail Safe Circuit

Check that the set returns to normal operation when pin 64 of N201 on the Main Board is grounded with

umper wire.

YES

Check if the voltage across capacitor C551 is approximately 17.2V

YES

Defective Fail Safe Circuit

Faulty Power Circuit o Horizontal Circuit

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

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 120 V/60 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.

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

RFAGC adjustment

FOCUS

Screen-grid voltage White balance adjustment

Scanning amplitude center & raster correction adjustment

High voltage check

X-ray protection check

Filament voltage check

Picture and sound check

Sub-brightness check

White balance check

Color purity convergence check

¡¢

AV term inal c heck

Check

The TV set & remote

controller's function check

Figure 1: Alignment flow chart

Factory adjustment mode

1. B+ voltage test

a) Make sure the AC power is 120 V/60 Hz

b) Connect digital voltmeter to B+ test point, receive A-7 signal, set picture control to“MEMORY 2” state,

test B+, the test voltage should be 100 V±0.3 V.

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) Press R-AGC button, 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 R-AGC button.

3. Focus adjustment

3. 1 Receive A-12 signal, set user control to “MEMORY 2” 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 RCUT value, adjust GCUT,BCUT,GDRV,BDRV’s value to make white

balance basically normal.

4.2 Set the color to 0, contrast to 30, 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).

Fig 2: red gun waveform

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

5.1 Item adjustment

VLIN 50Hz V-linearity adjustment

VSC 50Hz Vertical S-correction

VLIS 60Hz V-linearity adjustment

VSS 60Hz Vertical S-correction

5.2 PAL(50 Hz) H-center,V-center adjustment Receive D35 signal, set user control to “MEMORY 2” state, fine tune V-center VP50, H-center HPOS,

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

5.3 NTSC(60Hz)H-center,V-center adjustment Receive A6 signal, set user control to “MEMORY 2” state, adjust V-center VP60, H-center HPS to make

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

180V

6. Vertical scan amplitude adjustment

6.1 PAL(50 Hz)V-amplitude adjustment

Receive D35 signal, set user control to “MEMORY 2” state, adjust V-amplitude HIT, make picture’s upper

and lower overscanning be screen size’s 8%.

6.2 NTSC(60 Hz)V-amplitude adjustment

Receive A 12 signal, set user control to “MEMORY 2” state, adjust V-amplitude HITS to make picture’s

upper and lower overscanning be screen size’s 8%.

Checking point

1. High voltage check

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

1.2 Receive A-7 signal, set user control to “MEMORY 1” state, the high voltage should be 29.0 kV±1 kV.

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 A-7 signal, set picture control to “MEMORY 2” 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 A-7 signal, set user control to “MEMORY 2” state.

3.2 Short R554(TP501,TP502), 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 A-7 signal, set color ,contrast,brightness all to 0, picture’s left side first grid slightly lights.

6. This set can produce 28 kinds of testing signal by itself. Press “SLEEP PIC DSP MENU AV” button,

every time you press the buttons, one kind of testing signal will be produced. The first fourteen signals

are NTSC signal and the other fourteen signals are PAL signal. After these signals are cycled for one

time, it will return to original screen.

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

8 . AV t e r m in als ( AV I N /OUT c h e c k )

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

Preset the following in factory

1. Picture menu:

CONTRAST 100

BRIGHTNESS 50

COLOR 50

SHARPNESS 50 TINT ±00

PICTURE

MEMORY 4

MODE

▼MORE

2. Volume preset to 30.

3. Set OSD language to English.

4. Color system preset to AUTO.

5. TV mode:channel position number 2.

6. Firstly press SHOP OUT D/K SPOUT out-factory button on the factory remote controller,

“ready” will appear, wait for 8-10 seconds, the preset will be stored.

Factory menu

1. Enter into factory menu to operate.

1.1 Press “SLEEP PIC DSP MENU” button(The period of two-press should be within 5 seconds), enter into

factory menu.

1.2 Use MENU button to scroll the pages(P1,P2,P3).

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

2. Factory menu contents(

OSD

charac

ter

RCUT

GCUT

BCUT

GDRV

BDRV

Pre

set

06 HPOS 11 50Hz H-center MEMORY2 D35 screen

See below appendix 1.)

Appendix 1 Factory menu

Adjustment

Analogue

item

Dark area white

balance

Bright area

white balance

Contrast 0

Color 0

Bright 50

MEMORY1

setting

Input signal Adjustment methods Test point

Black/white

signal

horizontal

Make dark area obtain correct “white color”

screen

bright line.

Black/white

signal

Make dark area obtain correct “white color”

screen

VP50

HIT

VLIN

VSC

HPS

VP60

HITS

VLIS

VSS

RAGC

HAFC

V25

V50

TXCX

RGCN

ABL

06 50Hz V-center MEMORY2 D35

Adjust to make picture’s

vertical and horizontal

center be in accordance

with CRT center.

50Hz

V-amplitude

MEMORY2 D35

Cross-hatch

0B V-linearity MEMORY2

signal

(PAL)

Cross-hatch

signal

(PAL)

Vertical

S-correction

MEMORY2

03 60Hz H-center MEMORY2 A6 screen

Make V-amplitude meet

checking standard

screen

Adjust to make

screen’s upper and lower

cross-hatch height be

screen

equal.

Adjust to make screen’s

upper and middle and

lower cross-hatch

screen

height be equal.

Adjust to make picture’s

vertical and horizontal

03 60Hz V-center MEMORY2 A6

center be in accordance

screen

with CRT center.

60Hz

V-amplitude

60Hz V-linearity

fine tune

60Hz Vertical

S-correction

RF AGC

adjustment

1/2 AFC data

adjustment

25% volume

adjustment

50% volume

adjustment

YUV sub-color

maximum value

YUV sub-color

minimum value

Auto brightness

limitation

MEMORY2 A12

Cross-hatch

MEMORY2

signal

(NTSC)

Cross-hatch

MEMORY2

signal NTSC

MEMORY2 A7

A12 Fix

A21 Fix

Bright 50

Color 100

Contrast 50

Bright 50

Color 0

Contrast 50

In any

signal will

display

Let picture

without

color

MEMORY1 A7 fix Screen

To make V-amplitude

meet checking

screen

standard.

Adjust to make screen’s

upper and lower

cross-hatch height be

screen

equal.

Adjust to make screen’s

upper and middle and

lower cross-hatch

Screen

height be equal.

Adjust to make picture

without noise

Let character not

defocusing

N20143

Screen

Let character clear Screen

DCBS

CNTX

CNTC

CNTN

SCNT

BRTX

BRTC

BRTN

BRTS

COLX

COLC

COLP

COLN

TNTX

TNTC

TNTN

BIT4, 5 OSD

character

brightness level

BIT2, 3

Ygamma value

BIT 0,1 black

level stretch

value

Sub-contrast

maximum value

Sub-contrast

middle value

Sub-contrast

minimum value

MEMORY1 Gray scale Fix Screen

Contrast 50 Gray scale Fix Screen

Contrast 0

Color 0

Gray scale Fix Screen

Bright 50

0F Sub-contrast Natural Gray scale Fix Screen

Sub-bright

maximum value

Bright middle

value

Sub-bright

minimum value

Contrast 50

Bright 100

A7 Fix Screen

Color 0

MEMORY2 A7 Fix Screen

Contrast 50

Bright 0

A7 Fix Screen

Color 0

Contrast 0

1C Sub-bright

Bright 50

A7 Fix Screen

Color 0

Sub-color

maximum value

Sub-color

middle value

PAL sub-color

middle value

Sub-color

minimum value

Contrast 50

Bright 50

Color 100

Natural A7 Fix Screen

Natural D8 Fix Screen

Contrast 50

Bright 50

Color 0

Fix Screen

A7 Let picture without color Screen

Contrast

Sub-tint

maximum

value

100

Bright 50

Color 50

A7 Fix Screen

Tint 100

Sub-tint middle

value

Sub-tint

minimum

Natural A7 Fix Screen

Contrast

100

A7 Fix Screen

+ 25 hidden pages

Advent Q2016A Service Manual

Specifications and Main Features

Frequently Asked Questions

User Manual