TCL SY33 chassis – TCL25M63 TCL21M63 - slim CRT TV – how to enter service mode, circuit diagram, TEA1506 IC controlled SMPS schematic

Used ICs: 21C16 (Memory), LA76933 (Syscon: Chroma jungle), BCK3532(FBT), TEA1506P(SMPS control), LA78041(Vertical scan output), LA42352(Audio output), AS1213 (Remote control decoder: in the remote handset), 4052(Input selector) 

Method for Entering Factory Mode (Service Mode)
a. Production mode: Press the key [Fac] in remote control to enter or exit factory mode(But only display 4 pages);
b. Engineer mode: Press key [DISPLAY] to display channel information Setup for display picture on bottom left of screen, press the number key 6 1 5 8
c. Display “--PRODUCT--”，then press the key [MUTE] two times the factory menu on the screen.
The number on top right corner of factory menu is page number of factory menu. Press the key [CH+/-] to adjust courser up or down

Press the key [VOL+/-] to change the value.

When choose the first top line, press [VOL+] / [VOL-] to choose the menu page.

d. Press key [sleep] to display factory menu in production mode. Please choose next page when display factory menu.

e. Press key [0] to be shifted to one bright line status in production mode,. Press key [0] again to return factory menu.

Relevant key number for one bright line

[1] RB+ [2] GB+ [3] BB+

[4] RB- [5] GB- [6] BB

The main chip of SY33 chassis adopt IC LA76933 of SANYO company ,audio power amplifier adopts IC LA42352,power supply adopts IC STRW6553, and vertical scan amplifier adopts IC LA78041.The chassis has low cost and steady function, it has been adopts for 25M63,21M63 model.

TEA1506P IC based SMPS circuit diagram

The unit TV supports PAL/DK.I,AV supports PAL/NTSC system, in 2XAV,1x S-video.

SY33 chassis circuit includes tuner, IF ,SAWF,LA76933 H/V scan circuit ,AV board, side AV board, keypad board, USB board, power board. audio power amplifier circuit and power supply circuit etc. The main ICs are LA78041,LA42352,HPC922-C,L7809CV,L7805CV, LA76933,HCF4052 IC etc

RF from antenna enters tuner to be processed ( RF being inverted IF), and IF from pin11 of TU101 passes R106 ,C110 to Q101 IF preamplifier.

After amplifying, IF signal enters pin1 of Z101 to filter and separate SIF and PIF via pin4 and pin5 of Z101 into pin63 and pin64 of IC201(LA76933) to process PIF .

There are two ways output signal of process IF amplifier

One is video signal, from pin60 of IC201 , after R227,R228 adjustment ,it is sent pin56 of IC201 to process demodulation of picture.

Another way is sound signal, from pin5 of IC201 and passes C260 coupling. The sound signal is sent to pin1 and pin9 of IC901,after IC901 choosing, signal from pin3 and pin13 of IC901 is sent to pin2 and pin4 of IC601 to process sound power amplification. After amplifying,

Click on the circuit diagrams to magnify

The signals from pin8 and pin12 of IC601 is sent to L/R speaker.

Video signal of AV1from pin1 of P901 enters to pin46 of IC201 to decode process.
Sound signals of AV1from pin2 and pin3 of P901 input is sent to pin5 and pin 14 of IC901 to choose , after being choose, the signal flow same as TV sound.
AV2 signal process circuit.  Video signal of AV2 from pin4of P901 is sent to pin54 of IC201 to decode process.
Sound signals of AV2 from pin5 and pin6 of P901 is sent to pin1 and pin 12 to choose signal,. After being chose, the signal flow same as TV sound.

High-Definition signal flow.
Y signal from pin7 of P901 enters pin48 of IC201 to process video.
Cb signa from pin8 of P901 enters pin49 of IC201 to process video.
Cr signal from pin9 of P901 enters pin51 of IC201 to process video

Sound signal from pin27 and pin28 of IC201 enters pin6 and pin13 of IC601 to be amplified and be sent out form pin8 and pin12 of IC601

Mute control
Pin30 of IC201 sends mute control signal, and passes D002 to connect base of Q602,controls the Q602 ON or OFF, the pin C of Q602 connects pin5 of IC601 to control mute normal working .When Q602 off, pin5 of IC601 is high level. So pin8 and pin12 of sound signal output to speaker, when MCU sent mute signal of high level,Q602 ON, it lets the pin5 of IC601 is low level to shut down the sound signal of pin8/pin12 of IC601, the mute is working.

TU101 is a common tuner. The RF signal is processed by tuner inside circuit disposal :high frequency amplifier, mixing, high frequency demodulation, AGC, AFT, PLL.

Then IF output signal from pinIF of TU101 passes preamplifier Q101 to enter SAW Z101. The PIF signal from pin4 and pin5 of Z101, enters pin63 and pin64 of IC201 to be decoded.

Onkyo SKW-204(B)/(S)/(Y)-Powered Subwoofer Circuit diagram, exploded view, Current adjustment

Black, Silver and Yellow models

Adjustment of idling current

When
1. Exchange transistors (Q505 - Q519).
2. Exchange MAIN PC board ass'y (NAAF-8829)

Procedure

Note: No speaker load and No input signal.
1. Short test point P631 for amplifier is under active mode.
2. Adjust the trimming resistor R544 so that the reading of multi-meter becomes 52 ohm to 53 ohm.
3. Connect the DC voltmeter to test point P531. 

4. Connect the AC power cord into a wall outlet.
5. Press POWER button to turn on the unit.
6. Confirm the voltage of above point after 6 minutes to 8 minutes. (Heat running)
7. When less than 3.20 mV : Readjust the trimming resistor so that the voltage becomes 4.5 mV to 5.0 mV.
When 3.30 mV to 5.20 mV : Not necessary to adjust.
When 5.21 mV to 10.0 mV : Readjust the trimming resistor so that the voltage becomes 5.0 mV to 5.5 mV.
When 10.1 mV to 20.0 mV : Readjust the trimming resistor so that the voltage becomes 5.6 mV to 6.0 mV.
8. Press POWER button to turn off the unit.
9. Disconnect the DC voltmeter.
10. Disconnect the AC power cord from a wall outlet.

Circuit diagram (Schematic),PWB and Exploded view

Click on the pictures to magnify

LG EAY62811001- power supply board circuit diagram (schematic) and connector voltages - LG55LA6970 LED TV, LG55LA6900, LG55LP870H-UZ, LG55LA7400

Used ICs: IEC38R4765JZ, R2A20133D, SSC9527S, STD10NM50N(FET), EL817MB-DT(Photocoupler), R5F100BCAFP, IW7011A

Connector voltages

Circuit diagram

Click on the schematic to zoom in

How to enter service mode – Thomson DTH8040 DVD player – factory reset – SMPS (Transistorized) circuit diagram

Power supply board schematic, Initialization (Factory Reset) – Thomson DTH8040E, Thomson DTH8040U- DVD players

Service mode

> Connect the recorder to the mains supply and a monitor television using SCART lead.

> Switch ON the recorder and then press the Menu key on the remote control unit.

The recorders Main Menu will be displayed n the screen of the TV.

> Simultaneously press the Play and the Record keys on the front panel; and keep it depressed until the Service Menu is displayed on the screen of the TV.

Service mode screen

To re-initialize (Factory Setting)

* Switch ON the recorder and wait until the Menu is displayed at the front panel display.
* Simultaneously press the Stop and Standby/ON keys on the front panel, until the display changes to read INIT and then release the keys.
* When the recorder has been re-initialized, the display will flash INT OK for a split second.
Now all the previous setting will be reset to the original factory setting.
SMPS (Power supply unit circuit diagram) and PWB

Click on the pictures to magnify

LGP3739-13PL1 – part code: EAY62810401, EAX64905301 power supply unit circuit diagram and Connector voltages

LG 37, 39 and 42 inch LCD TV power supply unit schematic – 39LN549E, 39LN575V, 39LN5300, 39LN5700-UH, 

Used semiconductors: MAP3202SIRH, NR891D, SSCIS311A, MDF11N65B[FET]

On Condition: In a moment of Power ON Signal activated, the current of 3.5V output should be limited within 40mA(Max) at LCD TV condition for stability.
[Do not turn “Power ON” Signal on at the load condition of 3.5V output, more than 40mA]
 Total regulation for each output circuit includes the results of input voltage variation, load variation, warm-up drift and temperature change.
 Maximum input Wattage Rating: Under 85W
 The following instruments shall be used for measuring ripple noise.
1. Probe having impedance ratio of 1:1.
2. Oscilloscope having frequency characteristic of 100MHz or more.
 Ripple and noise are measured at the end of output cable which are added a 0.1uF ceramic capacitor and 47uF electrolytic capacitor.

Connector voltages

Click on the schematic to zoom in

Burn-in

More than 2 hours at 45℃(±5℃), Normal input voltage.

AC on/off must be test 1 time after burn-in.

80% Load of specification.

 This Power Supply has above-mentioned protections.

 Short circuit protection between different output terminals is not considered.

 Trip point for over voltage indicates the operating point when the output voltage slowly increases.

 The conditions of Over Current measurement

Multi output (3.5V,12V,24V) is nominal load state except an over current measurement.

Sanyo CE28DF-C (Europe)- how to enter service mode, service adjustments - Flyback transformer [LOT] number - 645 003 3094

Memory initialization, Gray scale adjustments, AGC and AFT adjustments, system control IC pin description and more… TDA8362,TDA7263, LA7833

Power source: ac 220~240v 50hz

Television system system: b/g, i,l/l’

Color system: PAL/SECAM

Receiving channel VHF: E2~E12

CATV: x,y,z, S1~S41

UHF: #21~#69

Aerial input impedance - 75Ohm

Power supply
The power supply circuit of the EB3-A chassis is composed of a rectifier smoothing circuit, an oscillation circuit, a control circuit and an output rectifier circuit. the ac input voltage is full-wave rectified by the rectifier smoothing circuit, and an unstable dc voltage is generated at both terminals of the smoothing capacitor C307. This voltage is input to the oscillation circuit. The oscillation circuit is provided with a blocking oscillator circuit that switches the switching FET Q301 on and off, and an oscillation frequency and a duty square wave pulse are generated in the input winding according to operation of the control circuit. A square wave pulse whose size is dependent on the turn ratio of the input and output winding is obtained in the output winding. This is rectified in the output rectifier circuit, and the desired dc voltage is obtained.

IF & deflection (TDA8362)
the if output signal from the tuner passes through the saw filter, and it is input to pin45 and pin46 of IC101. the signal input to the IC passes through the if amplifier, video detection and video amplifier circuits and is output from pin7 as a composite video signal. And after this signal is converted to impedance at Q122, supplies to the video and chroma amplifier stages.  The sync.-separation circuit separates the video signals applied to pin13(internal video signal) or pin15(external video signal) to vertical- and horizontal-sync signals respectively. The horizontal oscillator requires no external components and is fully integrated. The oscillator is always running when the start-pin36 is supplied with 8v. Horizontal drive signal is output from pin37. VR401 is for adjustment of the horizontal centering.  The separated vertical-sync signal from sync: separation circuit passes through the vertical-separation circuit, and applied to trigger divider circuit. the horizontal oscillation pulse and input vertical sync. pulse are monitored by the trigger divider circuit, and switching 50Hz and 60Hz system, the vertical amplitude automatically adjusted for 50Hz and 60Hz. the output signal from the trigger divider is triggered vertical oscillation circuit consisting of C401, R402 and pin42, and vertical drive pulse is output from pin43. VR451 is for changing the amount of AC feedback applied to pin41 and for adjustment of the vertical amplitude.

Video chroma & r.g.b. (tda8362)
The composite video signal output from the pin7 of ic101 passes through q122/q124, and it is supplied to pin13. The external video signal output from SCART is supplied to pin15. The video signal input to pin13 or pin15 is separated to luminance (y) signal and chroma signal in IC101. These pins are used in common with h/v-sync; separation input. The peaking of y signal is adjusted by dc voltage of pin14. (“sharpness” control) the chroma signal is divided into r-y and b-y chroma signals, demodulated in IC101, and output from pin30 (R-Y) and pin31 (B-Y). These chroma signals pass through the 1h delay line circuit (IC270), and they are input to pin29 (R-Y) and pin28 (B-Y). These R-Y/B-Y signals pass through RGB matrix circuit and RGB selector circuit of IC101. the internal RGB signals are generated in RGB matrix circuit and the RGB selector, consisting linear amplifiers, clamps and selects either the internal rgb signals or the external rgb signals input
from pin22(R), pin23(G), pin24(B). Selection is controlled by the voltage at the RGB switch control (pin21) and mixed RGB modes are possible since RGB switching is fast. The RGB switch also functions as a fast blanking pin by blanking the RGB output stages; here internal and external RGB signals are overruled. The color gain is controlled by dc voltage of pin26. (“Color” control)
The contrast control voltage present at pin25, and the brightness control voltage present at pin17 controls dc level of RGB signals. The RGB signals are finally buffered before being available at the RGB output pins [pin20 (R), pin19 (G), pin18 (B)]

Audio output (TDA7263M)

The audio signals output from the audio unit are input to pin1(L) and 5(R) of ic581 and passes through the preamplifier circuit and drive circuit, after which it is input to the audio amplifier. The audio amplifier is an SEPP (Single-Ended, Push-Pull) OTL type and output to pin8(R) and 10(L) to directly drive the speakers 

Vertical output (LA7833)

an IC (LA7833) is used for the vertical output circuit in this chassis. The vertical drive pulse from pin43 of ic101 is input to pin4 of IC451. This pulse drives IC451; and vertical scanning is performed. In the first half of scanning a deflecting current is output from pin2 and

passes through the following path:

vcc(b4) > d451 > pin3 > pin2 > dy > c461 > vr451/r459. an electric charge is then stored in c461.

In the last half of scanning the current path is c461 > DY > pin2 > pin1 > vr451/r459 > c461. in this way, an amplifying saw tooth waveform current flows directly to DY to perform electron beam defection. 

Next, in the first half of the banking period the vertical drive pulse suddenly becomes off, and in order to reduce the current flowing to DY, the current path becomes as follows by the inductance of DY:

DY > pin2 > pin1 > vr451/r459 > c461 > dy. also, when the charge of DY has dissipated, the current path becomes vcc24v > pin6 > pin7 > c452 > pin3 >pin2> dy > c461 > vr451/r459, and when the prescribed current value is reached, the vertical drive pulse becomes on. This completes one cycle.

Horizontal output

A horizontal oscillation signal is output from pin37 of ic101 and switches the drive transistor Q431. This switching signal is current amplified by the drive transformer T431 and drives the output transistor Q432.

When Q432 becomes on, an amplifying current flows directly to DY through c441/442 > DY > q432 > Gnd, and defection is performed in the last half of the scanning period. Next, when Q432 becomes off, the charge that had been stored in DY up to that point releases a

resonance current to the resonant capacitors c420 and c423 and charges them. The current stored in c420 and c423 is then flowed back to DY, and an opposite charge is then stored in DY. This opposite charge then switches the damper diode in Q432 ON, the resonance state is completed, and an amplifying current is then flowed again directly to DY through the dumper diode. By this means, deflection in the first half of the scanning period is performed, and when Q432 becomes on at the end of the first half of the scanning period, deflection during the last half is begun, thus completing one cycle.

CPU pin description

pin1: h-sync. input (horizontal pulse for osd)

pin2: v-sync. input (vertical pulse for osd)

pin3: colour control output

pin4: brightness control output

pin5: contrast control output

pin6: sharpness control output

pin7: tint (gnd)

pin8: tv/av output (l:av mode)

pin9: av mode selection output-a

pin10: av mode selection output-b

pin11: natioal select option

pin12: i2c bus scl (serial clock for memory)

pin13: i2c bus sda (serial date for memory)

pin14: not used (+5v through pull up resistor 22k)

pin15: ident signal input (l:no signal)

pin16: r/c signal input

pin17: av1 scart control signal input (vtr play:l)

pin18: av2 scart control signal input (vtr play:l)

pin19: ignor output

pin20: 50/60hz output

pin21/22: gnd

pin23: supply ground

pin24: oscillator input for cpu

pin25: oscillator output for cpu

pin26: supply ground

pin27: power supply(+5v)

pin28: oscillator output for osd

pin29: oscillator input for osd

pin30: reset input

pin31: protect signal input (l:power circuit defects)

pin32: not used(gnd)

pin33: aft signal input.

pin34: text/16:9 select option

pin35: key scan 1

pin36: p-on(text)

pin37: s-vhs output

pin38: gnd

pin39: bg/i select output

pin40: l/l’ select output

pin41: neg/pos select output

pin42: not used (gnd)

pin43: 16:9/4:3 switch output

pin44: not used (gnd)

pin45: not used (gnd)

pin46: not used (gnd)

pin47: mute output in no picture(ftz mute)

pin48: power on/off output (h:on)

pin49: blanking output for osd

pin50: not used (open)

pin51: green output for osd

pin52: red output for osd

Power supply adjustment
1. set vr351 to be mechanical centre before pressing the main switch.
2. tune the receiver to pal circular pattern.
3. set brightness and contrast controls to normal.
4. connect digital v-meter to test point "tp-b".
5. by using vr351, adjust voltage to 150 ± 0.5 v.

AFT adjustment
1. b/g/i area : tune the receiver to the clearest station on system bg. by using t121, adjust aft to obtain the best picture.
2. l/l’ area : tune the receiver to vl station on system l/l’. by using vc141, adjust aft to obtain the best picture.
3. if bg/i and l/l’ can be received adjust 1 and 2.

AGC adjustment
Note: Do not attempt this adjustment with weak signal.
1. tune the receiver to the clearest station.
2. set AGC vr(vr120) in direction which causes snow noise to appear, then in the opposite direction until snow noise just disappears.

Grey scale adjustment
screen vr adjustment
1. tune the receiver to the white pattern.
2. set brightness control to display centre and contrast control to normal.
3. set sw220 to "service" position.
4. set vr602 and vr612 to be mechanical centre.
5. turn vr601, vr611 and vr621 fully counter-clockwise.
6. set screen vr for one colour to be just visible.
bias vr adjustment
7. by using vr601, vr611 or vr621, adjust line to be white.
8. set sw220 to "normal" position.
drive vr adjustment
9. by using vr602 and vr612, adjust white balance.

High voltage & width adjustment 

[high voltage adjustment]

1. tune the receiver to pal circular pattern.

2. set brightness and contrast controls to maximum.

3. connect digital v-meter to both terminals of r232(left side)(+) , and high voltage meter to CRT anode.

4. confirm high voltage to be 26.0 ± 1 kv at beam current 1.3, and less than 29.0 kv at 0 beam current .

[h-width adjustment]

5. adjust vr462 to obtain proper H- width.

6. reconfirm high voltage.

H-center adjustment
1. tune the receiver to circular pattern.
2. adjust h-center by using vr401.

V-centre adjustment
1. tune the receiver to circular pattern.
2. adjust V-center by using sw451.
V-size adjustment
1. tune the receiver to circular pattern.
2. adjust v-size by using vr451.
focus adjustment
by using focus vr, adjust focus control for well scanning lines.

Initialization of memory IC

[When you replace a memory ic (IC731), it is necessary to initialize the IC as follows.]

1. Press and hold the function button on the TV set and then press the recall button on the RC transmitter, the following picture will appear on the screen. [Service mode]

Item -1 set> 0

2. Confirm set number of all items is "0" by pressing the function button.

3. If it is not "0", change to "0" by the level (+/-) button. (Changing the set number, automatically memorized.)

4. Press the recall button, to return the normal TV mode.

Stereo separation setting

1. To enter the service mode, press and hold function button on the tv set and then press the function button on the rc transmitter. the following picture will appear on the screen.

k2 > 32 [k2=service code, 32=service number]

2. set the service codes and numbers as below;

k1 > 16

k2 > 32

to change the service code, press the function button.

to change the service number, press the level (+/-) button.

3. Press the recall button to return to the tv mode.

4. Confirm the sound quality with stereo signal receiving.

Daewoo DTT3250, DTT3250MT CTV - How to enter service mode, adjustments, SMPS, deflection and audio output circuit diagram

STR X6757 (SMPS control), TDA8172A (Vertical output IC), BSC29-0185F (FBT)

THE ADJUSTMENT METHOD OF CP-750 WITH USER ROMOTE CONTROLLER (R-49C05)

Service Mode
To enter the service mode, press Red button and Green button and MENU key on (Ch.91)
Service Mode 1 is displayed. 

Press MODE key.

Service Mode 2 is displayed.

CONTROL KEY

MENU -  Return to former step

OK - Exit service mode

PR ▲/▼ - Select item

VOL ▲/▼- Change value or condition

SCREEN ADJUSTMENT
Service Mode 1 > DDPC 3316_1 > Screen
Adjust Screen Volume of FBT until the horizontal line is just disappeared.
FOCUS ADJUSTMENT
Adjust with the Focus volume on the FBT until you get the most clear resolution of 350 line
and corner of screen.
Focus volume on the FBT is consisting of two parts - vertical focus and horizontal focus.
WHITE BALANCE ADJUSTMENT

(1) High-Beam Adjustment
Service Mode 1 > Tube Measurement > WD_R, WD_G
Adjust R,G bars in the high beam on the instrument may be located in the center.(B DRV is Fixed.)
(2) Low-Beam Adjustment

Service Mode 1 > Tube Measurement > CUT_R, CUT_G
Adjust R,G bars in the low beam on the instrument may be located in the center.(B BIAS is Fixed.)

[The reference coordinates are X = 288, Y = 302”] PWB bottom view, SMPS and deflection schematic

VERTICAL CENTER Adjustment

Service Mode 1 > Vertical Geometry > Ver. Center

Adjust to harmonize RETMA pattern’s upper marking with Lower marking.

VERTICL SIZE Adjustment

Service Mode 1 > Vertical Geometry > Ver. Size

Adjust so that the Upper and the Lower ‘4’ marks of the RETMA pattern may be located at the boundaries of the screen.

HORIZONTAL CENTER Adjustment

Service Mode 1 > Hor. Geometry > Hor. Center

Adjust to harmonize the position of RETMA pattern’s Left side with Right side.

HORIZONTAL WIDTH Adjustment

Service Mode 1 > Hor. Geometry > Hor. Width

Adjust so that the Left and the Right ‘5’ marks of the RETMA pattern may be located at the boundaries of the screen.

PINCUSHION Adjustment 

(1) Parabola Adjustment

Service Mode 1 > Hor. Geometry > Cushion

Adjust so that the Left and Right edge’s vertical line may be straight.

(2) Corner Top/Bottom or Top 6th/Bottom 6th

Service Mode 1 > Hor. Geometry > Corner Top/Corner Bottom or Corner Top 6th/Corner Bottom 6th

Adjust so that the Upper and the Lower corner’s vertical line may be straight.

(3) Trapeze Adjustment

Service Mode 1 > Hor. Geometry > Trapeze

(4) Angle Adjustment

Service Mode 1 > Hor. Geometry > Angle

(5) Bow Adjustment

Service Mode 1 > Hor. Geometry > Bow.

TCL LE32E1600 – Side-lit LED LCD TV –– SMPS schematic

Power supply regulator board circuit diagram – TCL Side lit type LCD TV - TCL LE32E1600

Product Name: Side light type LCD TV
Product Model: LE32E1600;
Product movement: MST6M182
Remote control: RC06
Universal remote control set-up code to check with TCL brand TVs: 0398

Debugging instructions only for LCD TV movement debugging, commissioning before the need for all parts of the circuit assembly test, so that the Part of the circuit components without error, contact, leakage, leakage welding, when the part of the circuit in line with the circuit schematic and assembly requirements before Start debugging, debugging equipment used in advance must be metering, proofreading, to ensure accuracy, or shall not be used.

Instrument, instrument, operating tool configuration:

A. suitable for 6M182 movement of a LED tooling machine

B. a digital voltmeter

C. AC power supply one

D. factory standard signal cable input system

E. 40MHz dual trace oscilloscope.

Inspection methods

A. the motherboard and the appropriate tooling machine connected to connect the company debugging signal.

B. turn on AC 220V power supply, the machine into standby mode, press the remote control or the control of the boot button, boot into the standard state.

C. Press the remote control "program +" "program -" key to check the program number of the image and audio signals, should have color card, box, vertical Cards, color bars, digital photos, three primary colors and other different types of images and audio signals, requiring no leakage, such as leakage, Fill this signal with automatic search or manual search

D. receive PAL color test card signal, with the remote control volume, balance, contrast, brightness, color, sharpness control, Sound, the picture should be changed

E. TV standard check: receive PAL-D / K standard images and audio signals, in the search can automatically identify the image system and sound system; check the other images and sound system is correct.

F. external terminal input and output check: press the "source" button, the machine installed on the "source" menu, including: TV, AV, COMPONENT, PC, HDMI, USB, oscilloscope should be able to observe the corresponding sound, video input and output signals, tooling machine On the image and sound signal should be normal. Also need to detect whether the AV output signal is normal.

Power supply and LED driver circuit diagram

Products directly with AC power supply, power supply voltage on the TV back cover signs on the instructions. Connect one end of the AC power cord to the TV

The rear terminal tag is inserted into the power port and the other end is connected to the power outlet to complete the power connection. In a lightning or pay when the power supply is powered off, unplug the power plug and the antenna plug. The power cord does not allow any other things to be tipped or wound in the above, do not place the power cord where it may be destroyed.

Precautions

The display is a precision display device, the screen has a bright spot, dark spots, or red, green, blue and the like a little dead pixels

This is a normal phenomenon, not a bad product. A, the display screen for a long time to display the same still picture, it will leave a TV A blur, this damage is caused by improper use. The TV in the connection of various systems, the system may not match With the phenomenon, especially when connected to the computer, some graphics cards may not match, and the machine only to identify the refresh rate of 60HZ.

SMPS Iinverter part schematic

LED Driver schematic

Click on the pictures to zoom in

As the machine uses an embedded operating system, the software is more complex, may be in the work or standby software problems, such as If the restart can return to normal, it is not a fault.

Case prevention measures, product use and routine maintenance knowledge.

LCD screen material: the LCD screen looks like a solid black screen, in fact, this layer of the screen manufacturers will add a layer of special coating. The main function of this layer of special coating is to prevent the user in the use of other light source reflective and glare, while strengthening the LCD screen itself, the color contrast effect. But because the manufacturers use this layer of plating Membrane materials are not the same, of course, its durability will be different. So the user in the clean, do not:

You can wipe the screen surface with any alkaline solution or chemical solution. LCD panel stains are generally divided into species, one is due For the accumulation of dust in the air, one is the user inadvertently left the fingerprints and oil.

As the LCD panel itself is a complex physical structure design, so when wiping the LCD panel, do not use unknown cleaning solution, but cannot use water and alcohol solution. There are three errors here

1, with a soft cloth (glasses cloth) or paper towels to wipe the LCD screen, it is recommended to use a dedicated LCD wipes do not with glasses cloth and paper towels to wipe the LCD screen, it is easy to scratch the "squeamish" LCD screen. You can use a special LCD wipes such as Supermax2020 in the LCD panel gently wipe, in general, fingerprints and oil

The dirty is not as easy as the former, but it is not a problem if you use a dedicated LCD wiping cloth For the special LCD wipes used in special fibers, with a higher than ordinary high-end glasses cloth wipe the effect of more, and And soft will not scratch the screen, but also has the unique function of dissipating static electricity; special reminder: the general cloth and paper towel is LCD panel killer.

2, with clean water LCD screen. The use of water, liquid easily into the liquid crystal display and equipment inside, so Will cause the device circuit to short-circuit, thus burning expensive electronic equipment. For fingerprints and oil, water is still powerless.

3, with alcohol and some other chemical solvents to clean the LCD screen. In general, alcohol is a commonly used organic solution Agent, can dissolve some dirt is not easy to wipe, if only used to clean the display shell, but also no adverse effects.

But do not use alcohol to clean the LCD screen, because now the LCD screen, are coated with a special coating on the screen, So that the screen has a better display, once the use of alcohol to wipe the monitor screen, it will dissolve this layer of special coating, Display effect adversely affected. With chemical solvents even more undesirable, this chemical on the "arrogant" of the LCD panel Jane Straight is a devastating blow. If your screen is accidentally stained with fruit juice, saliva or coffee is not easy to clean stains, do not use paper towels or glasses cloth and the like to wipe hard, because it is easy to wipe the stains at the same time also Scrape the LCD screen; you can use liquid crystal special wipes such as SupermAX2020 sprayed with no amount of ionized water Supermax2020 slightly moist, and then go to wipe, you cannot only stains without traces of your LCD screen screen.

6, the main technical parameters (including the movement used, screen, power supply specifications)