Hisense TC14FS68, TC24FS2H, TDA9850 Schematic

CONTENTS

1. X - RAY RADIATION PRECAUTION

2. SAFETY PRECAUTION

3. PRODUCT SAFETY NOTICE

4. THE ALIGNMENT FLOW CHART

5. INSTALLATION AND SERVICE ADJUSTMENTS

6. USA CHANNEL FREQUENCY TABLE (181 CH)

7. WIRING DIAGRAM

8. BLOCK DIAGRAM

9. IC BLOCK DIAGRAM

10. TDA9850 BLOCK DIAGRAM

11. COMPONENT AND BOTTOM VIEW

12. SCHEMATIC DIAGRAM

13. ELECTRICAL PARTS LIST

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CAUTION: BEFORE SERVICING THE CHASSIS, READ THE “X-RAY RADIATION

PRECAUTION” “SAFETY PRECAUTION” ON PAGE 1 AND “PRODUCT SAFETY NOTICE” ON PAGE 2 OF THIS MANUAL.

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 28.5kV at zero beam current (minimum brightness) under a 120V AC power source. The high voltage must not, under any circumstances, exceed 30kV.

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.

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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 0.15 μF 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 0.2 milliamp. AC. Any value exceeding this limit constitutes a potential shock hazard and must be corrected immediately.

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 char acteristic as specified in the parts list may create shock, fire, X-RAY RADIATION or other hazards.

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THE ALIGNMENT FLOW CHART

PIF

To fit the front cabinet,

Focus

alignment, focus, high

BTSC, secret code setting, AV function check.

Control buttons, channels, white balance, sound, hit the set

Factory items’ adjustment

Heatrun for 2 hours

To fit the back cabinet

B+, AGC,H-frequency

external degaussing

Preheat for 30 minutes

White balance revoltage,

X-ray protection test, sound power test, CCD, V-chip,

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 c onvergence adjustments. This should be all that is necessary to achieve optimum receiver performance.

FOCUS ADJUSTMENT

Adjust the FOCUS control (on T471) 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 about 28.5kV.

4. Vary the BRIGHTNESS 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.

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

Check that the set returns to normal operation when pin

34 of N101 on the Main Board is grounded with jumper

Power Circuit or Horizontal Circuit

Check if the voltage across capacitor

C411 is approximately 21V.

2. Temporarily short R412 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

YES NO

YES

Faulty

Defective Fail Safe Circuit

PIF alignment

1) Apply DC 12V to output pin of N551(pin3 of N551 ) , connect pin7 of LA76814(N101)

to GND.

2) Apply 95dBμ, 45.75MHz RF signal to the tuner's IF pin through a 1000P ceramic

capacitor. Connect the DC voltameter's⊕pole to LA76814 pin 47 , ⊙ pole to GND.

Note: For LA76814 ES01 version, the voltameter's⊕pole should connect to pin50 .

3) Adjust T202 with a non-inductive screwdriver until the reading on the DC voltameter is DC

3.6V±0.01V.

B+ CHECK

1) Prepare the test equipment.

2) Use the DC voltameter at DC 200V position to test VD551⊕, i.e. B+.

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

then adjust RP551 to make B+ = 110V±0.5V.

Test point

VD551⊕ VD556⊕ VD554⊕ VD555⊕

DC(V) 110 25 15 18

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TEST EQUIPMENT

1) DC regulated power supply PAB18-1.8

2) Audio voltameter

3) Oscilloscope

4) High-voltage meter

5) Digital multimeter

6) AC voltameter

TEST MODE SET(CHECK) TEST MODE ADJUSTMENT INSTRUCTION

TEST MODE adjustment is a special adjustment which is controlled by I2C BUS. The TV set has been set at optimum mode at the factory. Except for special need, such as replacing CRT、 MEMORY 、IC etc., it is hoped not to adjust it. To conduct TEST MODE's adjustment, please do it according to the following steps :

There are two special romote controller for the set. One is "Under Adjustment" and the other is

"Under Adjustment for W/B Balance".

1) Press "PROD" button to enter the FACTORY, B/W BALANCE, ADJUST or SETUP mode.

2) In B/W BALANCE mode, select the item you want to adjust directly by pressing the button on

the"Under Adjustment for W/B Balance" remote controller and use the "ADJ+" or "ADJ-" button to adjust. You can press "ADJUP" or "ADJDOWN" to select needed adjustment item and use

the "ADJ+" or "ADJ-" button to adjust too.

3) In ADJUST mode, select the item you want to adjust directly by pressing the button on the "Under Adjustment" remote controller and use the "ADJ+" or "ADJ-" button to adjust. You can press

"ADJUP" or "ADJDOWN" to select needed adjustment item and use the "ADJ+" or "ADJ-" button to adjust too.

4) In SETUP mode, select the item you want to adjust by pressing the button "ADJUP" or

"ADJDOWN" on the "Under Adjustment". Then use the "ADJ+" or "ADJ-" button to adjust. adjust.

5) Press "PROD" to exit the TEST MODE.

H-blanking, H-center adjustment

1) Receive test signal, enter into the ADJUST mode.

2) Select the H.BLK.LEFT and H.BLK.RIGHT item, adjust the level to make the H -blanking amount on the left and right screen at an appropriate position.

3) Select the H.PHASE item, adjust the level to make the left and right picture sysmmetrical.

V-amplitude, linearity, S-correction, center adjustment

1) Receive test signal, enter into the ADJUST mode. adjust the value to make V-center and the CRT's

2) Select the V.POS item , adjust the value to make V-center and the CRT's geometric center is in accordance. Then select the V.SIZE item, adjust the value to make the overscan is less than or

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Equate 10% .

2) Select the V.LINE item, adjust the value to make the upper and lower grid's(on the screen) vertical

distance equal. Select the V.SC item, adjustthe value to make the vertical distance from upper

grid to middle screen is equal to the vertical distance from lower grid to middle screen.

3) Repeat the above steps 2) &3) to make the V-center, V-amplitude, V-linearity at the optimum

mode.

White balance, sub-brightness adjustment

1) Receive test signal, enter into B/W BALANCE mode with the special remote controller of

"Under Adjustment for B/W BALANCE".

2) Set the value of item as the following table:

Name

Name S-BRI

R-BIA G-BIA B-BIA R-DRV G-DRV B-DRV C.B/W

3) Set the value of S-BRI=85, then press "LINE" button. Adjust the SCREEN potentiameter

clockwise until a slight bright horizontal line appears on the screen. Adjust the value of

R-BIA, G-BIA and B-BIA, until the line change white. Press "LINE" button again. Then

decrease S-BRI to a proper value.

4) Press "LINE" button to exit B/W BALANCE mode.

Value 0~127 0~255

0~255

0~127 0~15 0~127

0~3

Default

Description

Sub Brightness Red Bias

Green Bias Blue Bias Red Drive Green Drive Blue Drive Cross B/W

ADJUST MENU LIST

Receive test signal, enter into ADJUST mode with the special remote controller of

"Under Adjustment".

Item 00* 01** 02** 03** 04* 05* 06* 07* 08** 09** 10** 11** 12

13 14 15

Name

H.PHASE NT.H.PHASE H.BLK.LEFT

H.BLK.RIGHT

V.SIZE V.LINE V.POSI

V.SC NT.V.SIZE NT.V.LINE NT.V.POSI

NT.V.SC

RF.AGC

VOL.OUT

OSD.H.POSI OSD.V.POSI

Description

H.PHASE

Vertical Size

Vertical Linearity

Vertical DC

Vertical S-Correction

RF AGC Delay

Volume Control

Value

0~31 0~31

0~7 0~7

0~127

0~31 0~63

0~31

-32~+31

-16~+15

-32~+31

-16~+15 0~63

0~127 0~127

0~31

Default

6 00 00 00

00 30

127

11 16

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16 17 18 19 21 22

INPUT LEVEL

SPECTRAL

WIDE BAND

STEREO

FILTER SET

SAP VCO

0~15 0~63

0~63 0~63 0~31 0~63

0 63 63 63

Note: 1.All the items sign with "*" can adjust to different value for different TV set.

2.All the items sign with "**" do not affect the IC of La76814.

ADJUST MENU LIST

Receive test signal, enter into ADJUST mode with the special remote controller of

"Under Adjustment".

Item 00 01 02 03 04 05 06 07 08 09

11 12

13 14 15 16 17 18 19 20

21 22 23 24

26 27

28 29 30 31 32 33 34 35

Name

LA76814/LA76812

SAP IC SELECT

SUB.CONT

SUB.COLOR

SUB.SHARP

SUB.TINT

BLK.STR.DEF

AFC GAIN

V.SETUP

CD.MODE

DIGITALOSD

OSD CONT GRAY MOD B.GAMSEL

RG.GAM.DEF

FBPBLK.SW

BRIGHT ABL.TH

EMG.ABL.DEF

BRT.ABL.DEF

MID.STP.DEF

R-Y/B-Y G.BL

R-Y/B-Y ANG

C.KILL.OFF

SND.TRAP

VOL.FIL

VIF.SYS.SW

VIDEO.LEVEL

FM.LEVEL

POWER OPT

POWER FLAG

SEARCH CHECK

SEARCH SPEED

AV OPTION

POSITION L/R

BLUE BACK

BLACK BACK

Description

0:LA76814; 1:LA76812

0:TDA9850; 1:CXA2104; 2:TDA9855; 3:UPC1851B

Subcontrast(0~31)

Subcolor(0~63)

Subsharpness(0~31)

Subtint(0~63)

Black Stretch Definition(0:on; 1:off)

AFC Gain(0:low; 1:high)

Vertical Synchronization Separate Sense(0:low; 1:high)

Count Down Mode(LA76814:0/1;LA76812:0~7)

Digital OSD(0:Analog; 1:Digital)

OSD Contrast(0~127)/LA76814(0~3)

Gray Mode(0/1)

Blue Selection(0~3)

Red&Green Definition(0/1)

FBPBLK.SW(0/1)

Bright.Abl.Threshold(0~7)

Emg.Abl.Def(0/1)

Brt.Abl.Def(0/1)

Mid.Stp.Def(0/1)

R-Y/B-Y Gain Balance(0~15)(None for)(LA76814)

R-Y/B-Y Angle(0~15)

C_Kill OFF(0/1)

Sound Trap(0~7)

Volume Filter Defeat(0/1)

Video IF(0:45.75M;1:58.75M)

Video Level(0~7)

FM Level(31)

0:Twice On; 1:Memory; 2or3:Once On

0:No Power On Screen;1:Power On Screen 0:No Power On Search;1:Power On Search

0:Slow;1:Quick

AV Input (0:No; 1:1; 2:2; 3:3)

Position of CH Number(0:Upper Left;1:Upper Right)

Blue Back When No Signal(0:Off; 1:On)

Black Back When Switch Channel(0:Off;1:On)

Default

0 0

1 1 0 1 2 0 2 0 0 0

0 0 8

8 0 3 1 0 7

1 0 1

1 1 0

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STEREO OPTION

36 37

WOOFER/H.PHONE

WOOFER VOL.OPT

39 40

42 43 44 45 46 47

SENSITIVITY V.MUTE P.OFF CCD OPTION

V-CHIP OPTION

PASSWORD OPT

COMB.OPTION

TUNER OPTION

GAME OPTION

SCREEN OPTION

Stereo Option(0:off;1:on)

0:Woofer;1:Headphone

Volume of H.Phone(0:No Woofer;1:Woofer)

Sensitivity Function(0:off;1:on)

Cut Video Out Before Power Off(0:on; 1:off)

CCD Function(0:off; 1:on)

V-CHIP Function(0:off; 1:on)

Password of V-CHIP(0:off;1:on)

Y/C Separate Function(0:off;1:on)

0:TDF-3M3;1:PHOLIPUV1336B

Game Option(0:on; 1:off)

0:No Screen;1:Screen When Power On;2:ScreenWhen Power Off;3:Screen When Power On/Off

1 0 0 0 0

1 0 1

1 0

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USA CHANNEL FREQUENCY TABLE

U.S.A. Channel PIF 45.75MHZ, CIF 42.17MHZ, SIF 41.25MHZ. UNIT:MHZ

Channel fp(picture) fs(sound) Channel fp(picture) fs(sound)

2 55.25 59.75 36 603.25 607.75 3 61.25 65.75 37 609.25 613.75 4 67.25 74.75 38 615.25 619.75 5 77.25 81.75 39 621.25 625.75 6 83.25 87.75 40 627.25 631.75 7 175.25 179.75 41 633.25 637.75 8 181.25 185.75 42 639.25 643.75

9 187.25 191.75 43 645.25 649.75 10 193.25 197.75 44 651.25 655.75 11 199.25 203.75 45 657.25 661.75 12 205.25 209.75 46 663.25 667.75 13 211.25 215.75 47 669.25 673.75 14 471.25 475.75 48 675.25 679.75 15 477.25 481.75 49 681.25 685.75 16 483.25 487.75 50 687.25 691.75 17 489.25 493.75 51 693.25 697.75 18 495.25 499.75 52 699.25 703.75 19 501.25 505.75 53 705.25 709.75 20 507.25 511.75 54 711.25 715.75 21 513.25 517.75 55 717.25 721.75 22 519.25 523.75 56 723.25 727.75 23 525.25 529.75 57 729.25 733.75 24 531.25 535.75 58 735.25 739.75 25 537.25 541.75 59 741.25 745.75 26 543.25 547.75 60 747.25 751.75 27 549.25 553.75 61 753.25 757.75 28 555.25 559.75 62 759.25 763.75 29 561.25 565.75 63 765.25 769.75 30 567.25 571.75 64 771.25 775.75 31 573.25 577.75 65 777.25 781.75 32 579.25 583.75 66 783.25 787.75 33 585.25 589.75 67 789.25 793.75 34 591.25 595.75 68 795.25 799.75 35 597.25 601.75

69 801.25 805.75

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