ILO DTV2794 Schematic

SERVICE MODE LIST

This unit is provided with the following SERVICE MODES so you can repair, examine and adjust easily. To enter to the SERVICE MODE function, press and hold both buttons simultaneously on the main unit or on the main unit and on the remote control for more than a standard time in the appropriate condition. (See below chart.) In case of the main unit and remote control, press the remote control buttons first, then press the main unit buttons.

Set

Condition

POWER ON

Set Key Operations

VOL. DOWN

(Minimum)

VOL. DOWN

(Minimum)

VOL. DOWN

(Minimum)

VOL. DOWN

(Minimum)

VOL. DOWN

(Minimum)

Remocon

Key

0 2 sec.

1 2 sec.

6 2 sec.

9 2 sec.

Standard

Time

2 sec.

Releasing of V-CHIP PASSWORD. Initialization of factory TV data.

NOTE:

Can be checked of the INITIAL DATA of MEMORY IC. Refer to the "WHEN REPLACING EEPROM (MEMORY) IC".

Check of the SUM DATA, MICON VERSION, POWER ON total hours and Digital TV MICON Firmware on the screen. Refer to the "WHEN REPLACING EEPROM (MEMORY) IC".

Display of the Adjustment MENU on the screen. Refer to the "ELECTRICAL ADJUSTMENT" (On-Screen Display Adjustment).

If you set factory initialization, the memories are reset such as the channel setting, and the POWER ON total hours.

WHEN REPLACING EEPROM (MEMORY) IC

CONFIRMATION OF CHECK SUM, POWER ON TOTAL HOURS, MICON VERSION AND DIGITAL TV MICON FIRMWARE VERSION

Initial total of MEMORY IC, POWER ON total hours, MICON VERSION and Digital TV MICON Firmware VERSION can be checked on the screen. Total hours are displayed in 16 system of notation.

NOTE:

If you set a factory initialization, the total hours is reset to "0". Please refer to "CONFIRMATION OF INITIAL DATA" when SUM DATA is not corresponding.

Turn on the POWER, and set to the TV mode.

1. Set the VOLUME to minimum.

2. Press both VOL. DOWN button on the set and Channel button (8) on the remote control for more than 2 seconds.

3. After the confirmation of each check sum, POWER ON total hours, Digital TV MICON Firmware and MICON VERSION,

4. turn off the power.

NOTE:

The each item value might be different according to each set.

ADDRESS DATA

CRT ON 0000

MICON Version

Digital TV MICON Firmware

Initial setting data check sum.

Rom correction data check sum.

OEC7174A_23 DTV CTT71222 INIT 26B2 ROM: 43EB

FIG. 1

C-1

POWER ON total hours.

= (16 x 16 x 16 x thousands digit value) + (16 x 16 x hundreds digit value) + (16 x tens digit value) + (ones digit value)

WHEN REPLACING EEPROM (MEMORY) IC

If a service repair is undertaken where it has been required to change the MEMORY IC, the following steps should be taken to ensure correct data settings while making reference to TABLE 1.

INIT +0 +1 +2 +3 +4 +5 +6 +7 +8 +9 +A +B +C +D +E +F

00 43 00 00 20 09 B 3 24 0D 4B 80 00 A 0 FA 00 00 00 10 00 00 00 65 4E 34 10 A1 00 00 00 00 60 00 10 8C 20 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 08 30 88 00 00 00 00 09 72 05 05 00 00 00 87 03 C 8 22 40 02 33 00 00 04 23 2D 20 00 40 20 40 40 40 00 00 50 00 64 00 00 00 00 00 00 0A 45 A0 00 FF 01 00 00 60 00 88 00 00 00 00 00 00 00 00 00 00 00 00 00 00 70 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 80 00 00 00 00 00 00 00 00 00 03 00 00 00 00 00 00

90 00 00 00 00 00 00 00 00 00 00 00 05 9D 01 00 84 A 0 04 11 00 00 00 05 00 01 00 00 00 05 12 13 05 82 B 0 01 00 00 00 00 04 00 04 00 02 00 00 00 00 00 00 C0 08 24 2F 33 37 38 39 3A 3B 3C 3C 3D 3F 40 40 41 D0 42 44 45 46 47 48 49 4A 4B 4C 4C 4D 4E 4F 50 50 E 0 51 52 53 53 54 54 55 55 57 58 5A 5B 5C 5D 5E 5F F0 61 62 64 66 68 6E 73 78 7D 82 86 8A 8E 8E 8F 8F

Table 1

CONFIRMATION OF INITIAL DATA

Enter DATA SET mode by setting VOLUME to minimum.

1. Press both VOL. DOWN button on the set and Channel button (6) on the remote control for more than 2 seconds.

2. ADDRESS and DATA should appear as FIG 2.

ADDRESS is now selected and should "blink". Using the CH. UP/DOWN button on the remote, step through the ADDRESS until required ADDRESS to be changed is reached.

Press VOL. UP/DOWN button to select DATA. When DATA is selected, it will "blink".

Again, step through the DATA using CH. UP/DOWN button until required DATA value has been selected.

Pressing VOL. UP/DOWN button will take you back to ADDRESS for further selection if necessary.

Repeat steps 3 to 6 until all data has been checked.

When satisfied correct DATA has been entered, turn POWER off (return to STANDBY MODE) to finish DATA input.

After the data input, set to the initializing of shipping.

Turn on the Power.

9. Set the VOLUME to minimum.

10. Press both VOL. DOWN button on the set and Channel button (1) on the remote control for more than 2 seconds.

11. After the finishing of the initializing of shipping, the unit will turn off automatically.

12.

The unit will now have the correct DATA for the new MEMORY IC.

ADDRESS DATA

INIT 00 43 CRT ON 0000 OEC7174A_23 DTV CTT71222 INIT 26B2 ROM: 43EB

FIG. 2

C-2

SERVICING FIXTURES AND TOOLS

Serial Communication Change JIG

Ref. No.

JG205

JG206

Part No.

APJG205000

APJG206000

APJG176125JG176

JG206JG205

Parts Name

Serial Communication Change JIG

Flash UP-Date Soft Disc

2007 SD DTV Rom Disc

Flash UP-Date Soft Disc

JG176

Connect the set to personal computer

Up-Date of the Firmware

Up-Date of the DIGITAL Firmware

2007 SD DTV Rom Disc

Remarks

RE-WRITE FOR DIGITAL SOFT FIRMWARE

Confirm that the AC cord is plugged out.

Using the Serial Communication Change JIG (JG205), connect the set to personal computer. (Refer to Fig. 1)

NOTE: It is possible to write only with the personal computer of WINDOWS.

Fig. 1

Using the Flash UP-Date Soft Disc (JG206) and USA SD DTV ROM DISC (JG176), please Re-write the DIGITAL SOFT FIRMWARE. The operating manual for Re-writing is included in Flash UP-Date Soft Disc (JG206).

C-3

ELECTRICAL ADJUSTMENTS

1. ADJUSTMENT PROCEDURE

circuits or replacing electrical parts or PCB assemblies.

CAUTION

•

Use an isolation transformer when performing any service on this chassis.

•

Before removing the anode cap, discharge electricity because it contains high voltage.

•

When removing a PCB or related component, after unfastening or changing a wire, be sure to put the wire back in its original position.

•

When you exchange IC and Transistor with a heat sink, apply silicon grease on the contact section of the heat sink. Before applying new silicon grease, remove all the old silicon grease. (Old grease may cause damages to the IC and Transistor.)

Prepare the following measurement tools for electrical adjustments.

1. Oscilloscope

2. Digital Voltmeter

3. Multi-sound Generator

4. Pattern Generator

On-Screen Display Adjustment

1. In the condition of NO indication on the screen. Press the VOL. DOWN button on the set and the Channel button (9) on the remote control for more than 2 seconds to appear the adjustment mode on the screen as shown in Fig. 1-1.

TV-A

4:3

00 OSD H

Use the Channel UP/DOWN button or Channel button (0-9) on the remote control to select the options shown in Fig. 1-2. Press the MENU button on the remote control to end the

3. adjustments.

To display the adjustment screen for TV-A, TV-D, AV and YUV mode, press the INPUT button on the remote control. Press the VOL.DOWN button on the set and the channel (9) on the remote control for more than 2 seconds.

Fig. 1-1

NO.

00 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 16 29 30 31

FUNCTION

OSD H OSD C CUT OFF H.POSI H BLK L H BLK R V. SIZE V. POSI V. LIN VS CORR V COMP R.BIAS G.BIAS B.BIAS R.DRV G.DRV B.DRV BRI.CENT BRI.MAX BRI.MIN

NO.

FUNCTION

CONT.CENT

CONT.MAX

CONT.MIN

COL.CENT

COL.MAX

COL.MIN

TINT CENT

SHARP.CENT

SHARP.MAX

SHARP.MIN

SUB BIAS

H.SIZE

PARABOLA

TRAPEZIUM

COR TOP

COR BTM

TEST STEREO

X-RAY

Fig. 1-2

2. BASIC ADJUSTMENTS

2-1: CONSTANT VOLTAGE

Place the set in AV MODE without signal.

Connect the digital voltmeter to the TP003.

Adjust the VR502 until the digital voltmeter is 130 ± 0.5V.

2-2: CUT OFF

Place the set in Aging Test for more than 15 minutes.

Place the set in AV MODE without signal.

Using the remote control, set the brightness and contrast to normal position.

Activate the adjustment mode display of Fig. 1-1 and press the channel button (02) on the remote control to select “CUT OFF”.

Adjust the Screen V olume until a dim raster is obtained.

2-3: WHITE BALANCE NOTE: Adjust after performing CUT OFF adjustment.

Place the set in Aging Test for more than 15 minutes.

1. Receive the white 100% signal from the Pattern

2. Generator.

Using the adjustment control, set the brightness and contrast to normal position.

Activate the adjustment mode display of Fig. 1-1 and press the channel button (11) on the remote control to select "R.BIAS".

Using the VOL. UP/DOWN button on the remote control, adjust the R.BIAS.

Press the CH. UP/DOWN button on the remote control to select the "R.DRIVE", "B.DRIVE", "G.BIAS" or "B.BIAS".

Using the VOL. UP/DOWN button on the remote control, adjust the R.DRIVE, B.DRIVE, G.BIAS or B.BIAS.

Perform the above adjustments 6 and 7 until the white color is achieved.

2-4: FOCUS

Receive the monoscope pattern.

Turn the Focus Volume fully counterclockwise once.

Adjust the Focus V olume until picture is distinct.

D-1

ELECTRICAL ADJUSTMENTS

2-5: BRIGHT CENT

Receive the monoscope pattern. (RF Input)

1. Set the screen mode to FULL.

2. Using the remote control, set the brightness and contrast

3. to normal position. Activate the adjustment mode display of Fig. 1-1 and

4. press the channel button (29) on the remote control to select "BRI. CENT". Press the VOL. UP/DOWN button on the remote control

5. until the white 10% is starting to be visible. Receive the monoscope pattern. (Audio Video Input)

6. Press the INPUT button on the remote control to set to

7. the AV mode. Then perform the above adjustments 2~5.

Receive the monoscope pattern.

Press the INPUT button on the remote control to set to the YUV mode.Then perform the above adjustments 2~5.

2-6: CONTRAST MAX

Receive an over 70dB color bar pattern. (RF Input)

Using the remote control, set the brightness and contrast to normal position.

Activate the adjustment mode display of Fig. 1-1 and press the channel button (33) on the remote control to select "CONT.MAX".

Press the VOL. UP/DOWN button on the remote control until the contrast step No. becomes "70".

Receive a broadcast and check if the picture is normal.

Receive the color bar pattern. (Audio Video Input)

Press the INPUT button on the remote control to set to the AV mode. Then perform the above adjustments 2~5.

Receive the monoscope pattern.

Press the INPUT button on the remote control to set to the YUV mode.Then perform the above adjustments 2~5.

Fig. 2-1

2-8: COLOR CENT

Receive the color bar pattern. (RF Input)

1. Using the remote control, set the brightness, contrast, color

2. and tint to normal position. Connect the oscilloscope to TP022.

3. Activate the adjustment mode display of Fig. 1-1 and

4. press the channel button (35) on the remote control to select "COL.CENT". Adjust the VOLTS RANGE VARIABLE knob of the

5. oscilloscope until the range between white 100% and 0% is set to 4 scales on the screen of the oscilloscope. Press the VOL. UP/DOWN button on the remote control

6. until the red color level is adjusted to 110 ± 10% of the white level. (Refer to Fig. 2-2) Receive the video color bar pattern. (Audio Video Input)

7. Press the INPUT button on the remote control to

8. set to the AV mode. Then perform the above adjustments 2~6. Receive the video color bar pattern.

9. Press the INPUT button on the remote control to set to the

10. YUV mode.Then perform the above adjustments 2~6. Receive the video color bar pattern.

11. Press the INPUT button on the remote control to set to the

12. DIGITAL mode.Then perform the above adjustments 2~6.

2-7: TINT

Receive the color bar pattern. (RF Input)

1. Using the remote control, set the brightness, contrast

2. and tint to normal position.

Connect the oscilloscope to TP024.

Activate the adjustment mode display of Fig. 1-1 and press the channel button (38) on the remote control to select "TINT". Press the VOL. UP/DOWN button on the remote control

5. until the section A becomes as straight line.

(Refer to Fig. 2-1)

Receive the monoscope pattern. (Audio Video Input)

6. Press the INPUT button on the remote control to set to

7. the AV mode. Then perform the above adjustments 2~5. Receive the monoscope pattern.

8. Press the INPUT button on the remote control to set to

9. the YUV mode.Then perform the above adjustments 2~5.

10.

Receive the monoscope pattern.

11.

Press the INPUT button on the remote control to set to the DIGITAL mode.Then perform the above adjustments 2~5.

white 100%

2-9: HORIZONTAL POSITION

Receive the monoscope pattern.

Using the remote control, set the brightness and contrast to normal position.

Activate the adjustment mode display of Fig. 1-1 and press the channel button (03) on the remote control to select “H.POSI”.

Press the VOL. UP/DOWN button on the remote control until the SHIFT quantity of the OVER SCAN on right and left becomes minimum.

D-2

110%

Fig. 2-2

ELECTRICAL ADJUSTMENTS

2-10: HORIZONTAL SIZE

Receive the monoscope pattern.

Using the remote control, set the brightness and contrast to normal position.

Activate the adjustment mode display of Fig. 1-1 and press the channel button (43) on the remote control to select "H.SIZE".

Press the VOL. UP/DOWN button on the remote control until the SHIFT quantity of the OVER SCAN on the right and left becomes 10± 3%.

2-14: TRAPEZIUM

Receive the crosshatch signal from the Pattern Generator.

Using the remote control, set the brightness and contrast to normal position.

Activate the adjustment mode display of Fig. 1-1 and press the channel button (45) on the remote control to select “TRAPEZIUM”.

Press the VOL. UP/DOWN button on the remote control until the both ends right and left vertical lines of the 1th length lines screen become parallel.

2-11: VERTICAL LINEARITY

Receive the monoscope pattern.

Using the remote control, set the brightness, contrast, to normal position.

Activate the adjustment mode display of Fig. 1-1 and press the channel button (08) on the remote control to select "V.LIN".

Press the VOL. UP/DOWN button on the remote control until the SHIFT quantity of the OVER SCAN on upside and downside becomes minimum.

2-12: VER TICAL POSITION

Receive the monoscope pattern.

1. Using the remote control, set the brightness and contrast

2. to normal position. Adjust the VR401 until the horizontal line becomes fit to

3. the notch of the shadow mask.

(Refer to Fig. 2-3)

horizontal line

Notch

2-15: PALABOLA CORR

Receive the chosshatch pattern.

Using the remote control, set the brightness and contrast to normal position.

Activate the adjustment mode display of Fig. 1-1 and press the channel button (44) on the remote control to select “PALABOLA”.

Press the VOL. UP/DOWN button on the remote control, so that the line becomes straight from the outside of the right and left.

2-16: COR TOP/BTM

Receive the crosshatch signal from the Pattern Generator.

Set the screen mode to FULL.

Using the remote control, set the brightness and contrast to normal position.

Activate the adjustment mode display of Fig. 1-1 and press the channel button (46) on the remote control to select “COR. TOP”.

Press the VOL. UP/DOWN button on the remote control until the both ends vertical lines become straight.

Activate the adjustment mode display of Fig. 1-1 and press the channel button (47) on the remote control to select “COR. BTM”.

Press the VOL. UP/DOWN button on the remote control until the both ends vertical lines of the screen become parallel.

Shadow mask

Fig. 2-3

2-13: VER TICAL SIZE

Receive the monoscope pattern.

Using the remote control, set the brightness and contrast to normal position.

Activate the adjustment mode display of Fig. 1-1 and press the channel button (06) on the remote control to select “V. SIZE”.

Press the VOL. UP/DOWN button on the remote control until the SHIFT quantity of the OVER SCAN on upside and downside becomes 9 ± 2%.

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