SHARP 27UC4 Service Manual

27UC4

SERVICE MANUAL

S13W427UC4///

COLOR TELEVISION

Chassis No. GB-3U

MODEL

In the interests of user-safety (Required by safety regulations in some countries ) the set should be restored to its original condition and only parts identical to those specified should be used.

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CONTENTS

Page

» ELECTRICAL SPECIFICATIONS .........................................................................................................1

» IMPORTANT SERVICE SAFETY PRECAUTION .................................................................................2

» LOCATION OF USER'S CONTROL .....................................................................................................4

» INSTALLATION AND SERVICE INSTRUCTIONS................................................................................5

» SERVICE ADJUSTMENT ...................................................................................................................10

» CHASSIS LAYOUT .............................................................................................................................14

» BLOCK DIAGRAM ..............................................................................................................................15

» DESCRIPTION OF SCHEMATIC DIAGRAMS & WAVEFORMS........................................................16

» SCHEMATIC DIAGRAMS...................................................................................................................17

» PRINTED WIRING BOARD ASSEMBLIES ........................................................................................26

» REPLACEMENT PARTS LIST ............................................................................................................30

» PACKING OF THE SET......................................................................................................................39

ELECTRICAL SPECIFICATIONS

POWER INPUT..................................................... 120V AC, 60 Hz

POWER RATING ................................................................... 115W

PICTURE SIZE ............................................ 2187cm2 (339sq inch)

CONVERGENCE ............................................................. Magnetic

SWEEP DEFLECTION .................................................... Magnetic

FOCUS ............................................... Hi-Bi-Potential Electrostatic

INTERMEDIATE FREQUENCIES

Picture IF Carrier Frequency ..................................... 45.75 MHz

Sound IF Carrier Frequency...................................... 41.25 MHz

Color Sub-Carrier Frequency .................................... 42.17 MHz

(Nominal)

AUDIO POWER

OUTPUT RATING .............. 3.0W + 3.0W (at 10% distortion and

Dual CH Operate)

SPEAKER

SIZE ..........................................................9 x 5 cm oval (2 pcs.)

VOICE COIL IMPEDANCE ............................ 16 ohm at 400 Hz

ANTENNA INPUT IMPEDANCE

VHF/UHF.....................................................75 ohm Unbalanced

TUNING RANGES

VHF-Channels...............................................................2 thru 13

UHF-Channels ............................................................14 thru 69

CATV Channels ...........................................................1 thru 125

(EIA, Channel Plan U.S.A.)

Specifications are subject to change without prior notice.

SHARP CORPORATION

This document has been published to be used for after sales service only. The contents are subject to change without notice.

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IMPORTANT SERVICE SAFETY PRECAUTION

Service work should be performed only by qualified service technicians who are thoroughly familiar with all safety checks and the servicing guidelines which follow:

WARNING

1. For continued safety, no modification of any circuit should be attempted.

2. Disconnect AC power before servicing.

3. Semiconductor heat sinks are potential shock hazards when the chassis is operating.

4. The chassis in this receiver has two ground systems which are separated by insulating material. The nonisolated (hot) ground system is for the B+ voltage regulator circuit. The isolated ground system is for the low B+ DC voltages and the secondary circuit of the high voltage transformer. To prevent electrical shock use an isolation transformer between the line cord and power receptacle, when servicing this chassis.

CAUTION: FOR CONTINUED PROTECTION AGAINST A RISK OF FIRE, REPLACE

4A 125V

ONLY WITH SAME TYPE 4A125V FUSE.

SERVICING OF HIGH VOLTAGE SYSTEM AND PICTURE TUBE

When servicing the high voltage system, remove the static charge by connecting a 10k ohm resistor in series with an insulated wire (such as a test probe) between the picture tube ground and the anode lead. (AC line cord should be disconnected from AC outlet.)

1. Picture tube in this receiver employs integral implosion protection.

2. Replace with tube of the same type number for continued safety .

3. Do not lift picture tube by the neck.

4. Handle the picture tube only when wearing shatterproof goggles and after discharging the high voltage anode completely .

X-RADIA TION AND HIGH VOLTAGE LIMITS

1. Be sure all service personnel are aware of the procedures and instructions covering X-radiation. The only potential source of X-ray in current solid state TV receivers is the picture tube. However, the picture tube does not emit measurable X-Ray radiation, if the high voltage is as specified in the "High Voltage Check" instructions. It is only when high voltage is excessive that Xradiation is capable of penetrating the shell of the picture tube including the lead in the glass material. The important precaution is to keep the high voltage below the maximum level specified.

2. It is essential that servicemen have available at all times an accurate high voltage meter. The calibration of this meter should be checked periodically.

3. High voltage should always be kept at the rated value

−no higher. Operation at higher voltages may cause a failure of the picture tube or high voltage circuitry and;also, under certain conditions, may produce radiation in exceeding of desirable levels.

4. When the high voltage regulator is operating properly there is no possibility of an X-radiation problem. Every time a color chassis is serviced, the brightness should be tested while monitoring the high voltage with a meter to be certain that the high voltage does not exceed the specified value and that it is regulating correctly.

5. Do not use a picture tube other than that specified or make unrecommended circuit modifications to the high voltage circuitry.

6. When trouble shooting and taking test measurements on a receiver with excessive high voltage, avoid being unnecessarily close to the receiver. Do not operate the receiver longer than is necessary to locate the cause of excessive voltage.

IMPORTANT SERVICE SAFETY PRECAUTION

1.5k ohm 10W

0.15 F

TEST PROBE

TO EXPOSED METAL PARTS

CONNECT TO KNOWN EARTH GROUND

(Continued)

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BEFORE RETURNING THE RECEIVER (Fire & Shock Hazard)

Before returning the receiver to the user, perform the following safety checks.

1. Inspect all lead dress to make certain that leads are not pinched or that hardware is not lodged between the chassis and other metal parts in the receiver.

2. Inspect all protective devices such as non-metallic control knobs, insulating materials, cabinet backs, adjustment and compartment covers or shields, isolation resistor-capacity networks, mechanical insulators, etc.

3. To be sure that no shock hazard exists, check for leakage current in the following manner.

• Plug the AC cord directly into a 120 volt AC outlet, (Do not use an isolation transformer for this test).

• Using two clip leads, connect a 1.5k ohm, 10 watt resistor paralleled by a 0.15µF capacitor in series with all exposed metal cabinet parts and a known earth ground, such as electrical conduit or electrical ground connected to earth ground.

• Use an AC voltmeter having with 5000 ohm per volt, or higher, sensitivity to measure the AC voltage drop across the resistor.

• Connect the resistor connection to all exposed metal parts having a return to the chassis (antenna, metal cabinet, screw heads, knobs and control shafts, escutcheon, etc.) and measure the AC voltage drop across the resistor. AII checks must be repeated with the AC line cord plug connection reversed. (If necessary, a nonpolarized adapter plug must be used only for the purpose of completing these check.) Any current measured must not exceed 0.5 milliamp. Any measurements not within the limits outlined above indicate of a potential shock hazard and corrective action must be taken before returning the instrument to the customer.

234567890123456789012345678901212345678901234567890123456789012123456789012345678901234567890121

SAFETY NOTICE

Many electrical and mechanical parts in television receivers have special safety-related characteristics. These characteristics are often not evident from visual inspection, nor can protection afforded by them be necessarily increased by using replacement components rated for higher voltage, wattage, etc. Replacement parts which have these special safety characteristics are identified in this manual; electrical components having such features are identified by "å" and shaded areas in the Replacement Parts Lists and Schematic Diagrams.

234567890123456789012345678901212345678901234567890123456789012123456789012345678901234567890121

For continued protection, replacement parts must be identical to those used in the original circuit. The use of substitute replacement parts which do not have the same safety characteristics as the factory recommended replacement parts shown in this service manual, may create shock, fire, X-radiation or other hazards.

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Front Panel

CHANNEL UP/DOWN

( ) Selects next higher channel. ( ) Selects next lower channel.

VIDEO/AUDIO TERMINALS

IN 2

Press → Accesses MAIN MENU. Press again → Exits MAIN MENU

Note:

The above shaded buttons on the Remote Control glow in the dark. To use the glow-in-the-dark display on the remote control, place it under a fluorescent light or other lighting. The phosphorescent material contains no radioactive or toxic material, so it is safe to use. The degree of illumination will vary depending on the strength of lighting used. The degree of illumination will decrease with time and depending on the temperature. The time needed to charge the phosphorescent display will vary depending on the surrounding lighting. Sunlight and fluorescent lighting are the most effective when charging the display.

1 2 3 4 5 6 7 8 9

100

POWER

MENU MUTE

PA USE

PIP

FLASHBACK

DISPLAY

INPUT

TV • CATV • VCR • DVD

STOP REC

REW PLAY FF

CH/SKIP

SWAP FREEZE MOVE SELECT

VOL

—

VOL

ENTER

A B C D

PERSONAL PREFERENCE

DVD VCR

CATV TV

DVD VCR

Basic Remote Control Functions

VOLUME UP/DOWN

( ) Increases sound.+ ( ) Decreases sound.

POWER

Press → On. Press again → Off..

REMOTE KEYPAD

Accesses any channel from keypad.

FLASHBACK

Returns to previous channel.

PERSONAL PREFERENCE

With the Personal Preference buttons, you can program your favorite programs by using the 4 categories A, B, C and D. The channels can be accessed quickly by using these buttons.

VOLUME UP/DOWN

(+ ) Increases sound. (

) Decreases sound. Changes or selects the TV adjustments on On-Screen Displey.

Press → Accesses MAIN MENU. Press again → Exits MAIN MENU.

DVD/VCR CONTROL

CATV/DVD-TV/VCR MODE SELECT SWITCH

In TV/VCR position, signals sent will be for TV and VCR control. In CA TV/D VD position, signals sent will be for cable TV converter and DVD control.

Infrared Transmitter Window

DISPLA Y

Press Displays receiving channel for 4 seconds. Press again Removes display.

Temporarily displays receiving channel when in Closed Caption mode.

INPUT

Press Switches to external video INPUT 1 mode. Press twice Switches to external video INPUT 2 mode. Press 3 times Switches to external video INPUT 3 mode or COMPONENT mode. Press 4 times Switches back to the original TV mode.

ENTER

Used in some instances where a Cable Converter Box requires an enter command after selecting channels, when using the REMOTE KEYPAD button.

CHANNEL UP/DOWN

( ) Selects next higher channel. ( ) Selects next lower channel.

Moves the Æ mark on the MENU screens.

MUTE

Press → Mutes sound. Press again → Restores sound.

When sound is muted, CLOSED

CAPTION appears if available.

PIP FUNCTION

With the VIDEO inputs, you can watch two pictures at the same time.

POWER

Press → On. Press again → Off.

REMOTE CONTROL

SENSOR

LOCATION OF USER'S CONTROL

' "

→

' "

INSTALLATION AND SERVICE INSTRUCTIONS

Note: (1)When performing any adjustments to resistor controls and transformers use non-metallic

screwdrivers or TV alignment tools.

(2)Before performing adjustments, the TV set must be on at least 15 minutes.

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CIRCUIT PROTECTION

The receiver is protected by a 4.0A fuse (F701), mounted on PWB-A, wired into one side of the AC line input.

X-RADIA TION PROTECT OR CIRCUIT TEST

After service has been performed on the horizontal deflection system, high voltage system, B+ system, test the X-Radiation protection circuit to ascertain proper operation as follows:

1. Apply 120V AC using a variac transformer for accurate input voltage.

2. Allow for warm up and adjust all customer controls for normal picture and sound.

3. Receive a good local channel.

4. Connect a digital voltmeter to TP651(pin 3) and make sure that the voltmeter reads 13.65 ±0.6V DC.

5. Apply external 17.3V DC at TP651 by using an external DC supply, TV must be shut off.

6. To reset the protector, unplug the AC cord and plug the AC cord power on. Now make sure that normal picture appears on the screen.

7. If the operation of the horizontal oscillator does not stop in step 5, the circuit must be repaired before the set is returned to the customer.

HIGH VOLTAGE CHECK

High voltage is not adjustable but must be checked to verify that the receiver is operating within safe and efficient design limitations as specified checks should be as follows:

1. Connect an accurate high voltage meter between ground and anode of picture tube.

2. Operate receiver for at least 15 minutes at 120V AC line voltage, with a strong air signal or a properly tuned in test signal.

3. Enter the service mode and select the service adjustment "V1 1" and Bus data "01" (Y-mute on, CRT Cut Off).

4. The voltage should be below 30.5kV (at zero beam). If a correct reading cannot be obtained, check circuitry for malfunctioning components. After the voltage test, make Y-mute off to the normal mode.

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For adjustments of this model, the bus data is converted to various analog signals by the D/A converter circuit.

Note: There are still a few analog adjustments in this series such as focus and master screen voltage.

Follow the steps below whenever the service adjustment is required. See "Table-B" to determine, if service adjustments are required.

1. Service mode

Before putting unit into the service mode, check that customer adjustments are in the normal mode. Use the reset function in the video adjustment menu to ensure customer controls are in their proper (reset) position.

2. Service number selection

Once in the service mode, press the Ch-up or Chdown button on the remote controller or at the set. The service adjustment number will vary in increments of one, from "V01" to "P08". Select the item you wish to adjust.

3. Data number selection

Press the Vol-up or V ol-down button to adjust the data number.

DA TA NUMBER

SERVICE ADJUSTMENT NUMBER

To enter the service mode and exit service mode.

To enter the service mode manually just press and hold the Vol-down and Ch-up buttons at the same time, plug the AC cord into a wall socket. Now the TV set is switched on and enters the service mode. To exit the service mode, turn the television off by pressing the power button.

CHANNEL

V01

Figure A.

55(085)

A. VCJ IC ADJUSTMENT

SERVICE

NUMBER

V01 PICTURE 0-15 (00h-0Fh) 8 (08h) V02 TINT 0-127 (00h-7Fh) 66 (42h) V03 COLOR 0-127 (00h-7Fh) 56 (38h) V05 BRIGHT 0-127 (00h-7Fh) 64 (40h) V06 R CUT-OFF 64-255 (40h-FFh) 64 (40h) V07 G CUT-OFF 64-255 (40h-FFh) 64 (40h) V08 B CUT-OFF 64-255 (40h-FFh) 64 (40h) V09 G/R DRIVE 0-127 (00h-7Fh) 64 (40h) V10 B DRIVE 0-127 (00h-7Fh) 64(40h) V11 Y-MUTE/V-STOP 0-2 0 (00h) Y-Mute / Holizontal "–" V12 SHARP 0-63 (00h-3Fh) 50 (32h) 32 V13 DC RESTORATION 0-3 (00h-03h) 2 (02h) 02 V14 BLACK STRETCH 0-3 (00h-03h) 2 (02h) 02 V15 ABL START POINT 0-3 (00h-03h) 3 (03h) 03 V16 ABL GAIN 0-3 (00h-03h) 2 (02h) 02 V17 γ POINT 0-3 (00h-03h) 0 (00h) 00 V19 ENERGY SAVE 0-63 (00h-3Fh) 63 (3Fh) Offset 3F V24 LOW-G 0-255 (00h-FFh) 12 (0Ch) Color Temp. F4 V25 LOW-B 0-255 (00h-FFh) 241 (F1h) Color Temp. E6 V26 ML-G 0-255 (00h-FFh) 0 (00h) Color Temp. FD V27 ML-B 0-255 (00h-FFh) 247 (F7h) Color Temp. F8 V28 HIGH-G 0-255 (00h-FFh) 2 (02h) Color Temp. 01 V29 HIGH-B 0-255 (00h-FFh) 8 (08h) Color Temp. 06 V30 WPL 0-1 1 (01h) 01 V31 RGB CONTRAST 0-63 (00h-3Fh) 59 (3Bh) 3B V34 VSM GAIN 0-3 (00h-03h) 1 (01h) 01 V36 BPF/TOF-INPUT 0-1 0 (00h) External Input 00 V37 CORING 0-1 0 (00h) 00 V38 VSM PHASE 0-1 0 (00h) 00 V39 COLOR γ 0-1 0 (00h) 00 V40 SHARP-INPUT 0-63 (00h-3Fh) 44 (2Ch) External Input 2C V41 TINT-INPUT 0-127 (00h-7Fh) 62 (3Eh) External Input 3E V42 PICTURE-COMPONENT 0-15 (00h-0Fh) 6 (06h) Component Input V43 TINT-COMPONENT 0-127 (00h-7Fh) 62 (3Eh) Component Input 3E V44 COLOR-COMPONENT 0-127 (00h-7Fh) 72 (48h) Component Input 48 V45 BRIGHT-COMPONENT 0-127 (00h-7Fh) 84 (54h) Component Input V46 R CUT OFF-COMPONENT 64-255 (40h-FFh) 64 (40h) Component Input V47 G CUT OFF-COMPONENT 64-255 (40h-FFh) 64 (40h) Component Input V48 B CUT OFF-COMPONENT 64-255 (40h-FFh) 64 (40h) Component Input V49 G/R DRIVE-COMPONENT 0-127 (00h-7Fh) 64 (40h) Component Input V50 B DRIVE-COMPONENT 0-127 (00h-7Fh) 64 (40h) Component Input V51 SHARP-COMPONENT 0-63 (00h-3Fh) 44 (2Ch) Component Input 2C V52 TINT-S 0-127 (00h-7Fh) 62 (3Eh) S terminal input. 3E V53 C-TRAP 0-1 (00h-01h) 0 (00h) 00 V59 AUTO FLESH 0-1 (00h-01h) 0 (00h) 00 V60 SHARP P F 0-1 (00h-01h) 1 (01h) 01 V61 CD MATRIX 0-3 (00h-03h) 2 (02h) 02 V62 B-Y A TT 0-1 (00h-01h) 0 (00h) 00 V63 R-Y A TT 0-1 (00h-01h) 0 (00h) 00 V64 CD MATRIX-COMPONENT 0-3 (00h-03h) 0 (00h) Component Input 00 V65 B-Y A TT -COMPONENT 0-1 (00h-01h) 0 (00h) Component Input 00 V66 R-Y A TT -COMPONENT 0-1 (00h-01h) 0 (00h) Component Input 00 V67 BUZZ 0-1 (00h-01h) 1 (01h) 01 V68 RGB ABCL 0-1 (00h-01h) 1 (01h) 01 R01 RF-AGC 0-63 (00h-3Fh) 36 (24h) R03 RF-AGC REF 0-255 (00h-FFh) 170 (AAh) D01 V POSITION 0-7 (00h-07h) 0 (00h) 00 D02 H POSITION 0-31 (00h-1Fh) 15 (0Fh) D03 V SIZE 0-127 (00h-7Fh) 89 (59h) D04 H SIZE 0-63 (00h-3Fh) 36 (24h) D05 V-LINEARITY 0-15 (00h-0Fh) 8 (08h) D06 V-S CORRECTION 0-15 (00h-0Fh) 12 (0Ch) 0C D07 EW PARABOLA 0-63 (00h-3Fh) 43 (2Bh) D08 EW TRAPEZIUM 0-63 (00h-3Fh) 36 (24h) D10 AFC GAIN 0-3 (00h-03h) 2 (02h) 02 D11 V EHT 0-7 (00h-07h) 6 (06h) 06 D12 H EHT 0-7 (00h-07h) 6 (06h) 06 D13 EW CORNER 0-31 (00h-1Fh) 8 (08h) 08

ADJUSTMENT ITEM

RANGE

DA T A

NOTE

INITIAL VALUE

Standard value for the self-adjustment

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FIXED VALUE

(HEX)

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SERVICE

NUMBER

D14 EW CORNER BOTTOM 19-81 (13h-51h) 50 (32h) Offset toward D13. 32 D15 NOISE DET LEVEL 0-3 (00h-03h) 0 (00h) 00 D18 V CENTERING 0-63 (00h-3Fh) 36 (24h) D19 V-AGC 0-1 (00h-01h) 0 (00h) 00

ADJUSTMENT ITEM

RANGE

DA T A

INITIAL VALUE

NOTE

B. SPECIAL SETTING

SERVICE

NUMBER

EX1 FAO VOLUME 0-50 (00h-32h) 36 (24h) 24 EX2 CC-POSITION 0-127 (00h-7Fh) 27 (1Bh) 1C EX3 INT 0-255 (00h-FFh) 122 (7Ah) Interrupt period adjustment. 7A EX4 A-ATT 0-127 (00h-7Fh) 90 (5Ah) 5A EX5 TUNER data 0-3 (00h-03h) 0 (00h) 00 EX6 Think chip-Slice LEVEL 0-255 (00h-FFh) 54 (36h) 12 EX7 RLY DELAY TIME 0-255 (00h-FFh) 0 (00h) For the power control 00 EX8 ADG ON TIME 0-255 (00h-FFh) 10 (0Ah) For the power control 0A

ADJUSTMENT ITEM

RANGE

DA T A

NOTE

INITIAL VALUE

C. OPTION SETTING

SERVICE

NUMBER

OP1 OPTION1 0-255 (00h-FFh) 247 (F7h) B7 OP2 OPTION2 0-255 (00h-FFh) 253 (FDh) 3C OP3 OPTION3 0-255 (00h-FFh) 15 (0Fh) 0C

ADJUSTMENT ITEM

RANGE

DA T A

NOTE

INITIAL VALUE

FIXED VALUE

(HEX)

FIXED VALUE

(HEX)

FIXED VALUE

(HEX)

D. SOUND ADJUSTMENT

SERVICE

NUMBER

M01 INPUT LEVEL 0-15 (00h-0Fh) 7 (07h) M02 MTS VCO 0-63 (00h-3Fh) 38 (26h) M03 FILTER 0-63 (00h-3Fh) 36 (24h) M04 WIDEBAND 0-63 (00h-3Fh) 28 (1Ch) M05 SPECTRAL 0-63 (00h-3Fh) 23 (17h)

ADJUSTMENT ITEM

RANGE

DATA

NOTE

INITIAL VALUE

E. PIP IC ADJUSTMENT

SERVICE

NUMBER

P01 CONTRAST-PIP 0-127 (00h-7Fh) 73 (49h) P02 TINT-PIP 0-63 (00h-3Fh) 41 (29h) 29 P03 COLOR-SAT-PIP 0-127 (00h-7Fh) 68 (44h) P04 Y-OFFSET-PIP 0-31 (00h-1Fh) 9 (09h) 09 P05 HXA-PIP 0-255 (00h-FFh) 10 (0Ah) 0A P06 HADJ-PIP 0-15 (00h-0Fh) 0 (00h) 00 P07 FREE RUN-PIP 0-15 (00h-0Fh) 11 (0Bh) 0B P08 TINT-PIP-INPUT 0-63 (00h-3Fh) 36 (24h) External input for sub screen 24

ADJUSTMENT ITEM

RANGE

DATA

NOTE

INITIAL VALUE

FIXED VALUE

(HEX)

FIXED VALUE

(HEX)

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Holding down both the VOL-up and CH-up buttons on the TV set at service mode for more than 2 seconds will automatically write the above initial values into IC2101.

PART REPLACED

IC2001 IC201

IC2101

CRT IC3001

IC1801

NECESSARY UNNECESSARY

ADJUSTMENT

X X X

NOTES

Data is stored in IC2101. The adjustment is needed to compensate for characteristics of parts

including IC201 and MTS level (M01). Holding down both the VOL-up and CH-up buttons on the TV set in

the service mode for more than 2 seconds will automatically write the above initial values into IC2101 Then perform a complete adjustment.

Adjust items related to picture tube only. Adjust items related to MTS only (M01~M20).

Adjust items related to P-IN-P only (P01~P08).

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SERVICE ADJUSTMENT

RF AGC Adjustment

1. Receive a good local channel.

2. Enter the service mode and select the service adjustment "R01".

3. Set the data value to point where no noise or beat appears.

4. Select another channel to confirm that no noise or beat appears. Note 1 : You will have to come out of the service

mode to select another channel.

Note 2 : Setting the data to "00" will produce a black

raster.

Screen Adjustment

1. Receive a good local channel.

2. Enter the service mode and select the service adjustment "V03" and set the data value to "00" to set the color level to minimum. (Record original data code under adjustment "V03" before changing) You may skip this step, if you selected a B/W picture or monoscope pattern.

3. Select the service adjustment "V11" and adjust the data value to "01", this turn off the luminance signal (Y-mute).

4. Adjust the master screen control until the raster darkens to the point where raster is barely seen.

5. Adjust the service adjustments "V06" red, "V07" green and "V08" blue to obtain a good grey scale with normal whites at low brightness level.

6. Select the service adjustment "V11" and reset data to "00". Select the service adjustment "V03" and reset data to obtain normal color level.

7. For component input, the data value of "V46" red, "V47" green and "V48" blue is adjusted to follow the data value of "V06", "V07" and "V08" respectively.

8. Reset the master screen control to obtain normal brightness range.

White Balance Adjustment

1. Receive a good local channel.

2. Enter the service mode and select the service adjustment "V03" and set to "00" (minimum color)(Record original data code under adjustment "V03" before changing). "V03" does not have to be adjusted, if you selected a B/W picture or monoscope pattern.

3. Alternately adjust the service adjustment data of "V09" and "V10" until a good grey scale with normal whites is obtained. (RF Input)

4. For component input, the data value of "V49" and "V50" is adjusted to follow the data value of "V09" and "V10" respectively.

5. Select the service adjustment "V03" and reset data to obtain normal color level.

Sub-picture and Sub-Bright Adjustments

1. Receive the window pattern signal.

• RF INPUT (TU51)

2. Get into service adjustment data "V01" and "V05" and set the luminance as shown in figure "A" and "B" as below respectively.

• COMPONENT INPUT

3. Get in service adjustment data "V42" and "V45" and set the luminance as shown in figure "A" and "B" as below respectively.

LUMINESCENCE CONFIRMATION

A: 86±10cd/m B: 1.25±0.5cd/m

Sub-Tint Adjustment

1. Receive the half color bar signal.

• RF INPUT (TU51)

2. Get into Y-Mute by R/C, or by setting the "V11" bus data to "01".

3. V ary the "V02" bus data until the waveform becomes as stated below.

LEVEL

B-AMP Base waveform in step (TP47B)

Sub-Color Adjustment

1. Receive a good local channel.

2. Make sure the customer color control is set to center position .

• RF INPUT (TU51)

3. Enter the service mode and select service adjustment "V03".

4. Adjust "V03" data value to obtain a normal color level.

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Focus Adjustment

1. Receive a good local channel.

2. Adjust the focus VR of the flyback transformer to make the image as fine as possible.

C. C Display Position Adjustment

1. Receive the lion head pattern signal.

2. Select "EX2" to display the text box.

3. Adjust the "EX2" bus data to let the text box displayed in the center.

DISPLAY OF TEXT BOX

TEXT BOX

SPEC INSPECTION:| A-B | / 2

| A-B | / 2

5mm

Vertical-Size and Linearity Adjustments

1. Receive a good local channel.

2. Enter the service mode and select the service adjustment "D03" for V-size.

3. Adjust the "D03" bus data to get the proper V -size.

4. For V-linearity adjustment, select data bus "D05" and adjust to get the proper vertical linearity. Note: Aging for 10 min before adjustment. After the

adjustment of V-center and V-size, readjustment for this V-line.

Vertical Phase Adjustment

1. Enter the service mode and input "D01" data value to "00h".

2. Adjust "D18" data value so that picture is centered.

Horizontal Position Adjustment

1. Receive a good local channel.

2. Enter the service mode and select the service adjustment "D02".

3. Adjust "D02" data value so that picture is centered.

MTS ADJUSTMENT

MTS Level Adjustment

1. Set the sound volume above 1. Monoral signal: 400Hz, 100% modulation

2. Confirm "EX4" data is "5Ah".

3. Vary the "M01" bus data until the voltage to pin (39) of IC3001 to become the value as stated below. SETTING VOLTAGE

ADJ spec : 490±10mVrms CHK spec: 490±20mVrms

MTS VCO Adjustment

1. Keep the unit in no-signal state.

2. Connect the frequency counter to pin (39) of IC3001.

3. Connect a capacitor (100µF, 50V) in between positive(+) side of C3005 and ground.

4. Enter the service mode and select the service adjustment "M02"

5. Adjust the data so that the frequency counter reads

62.94 ±0.75kHz.

Filter Adjustment

1. Feed the following stereo pilot signal to pin (14) of IC3001 at C3005 open. Stereo pilot signal: 9.4kHz, 600mVrms.

2. Enter the service mode and select the service adjustment "M03".

3. Adjust the data until "OK" appears in position on the screen. Make sure the "OK" is displayed almost at the center of the data range.

Separation Adjustment

1. Input "SIGNAL 1" and vary the "M04" bus data to get the minimun AC voltage to pin (39) of IC3001.

2. Input "SIGNAL 2" and vary the "M05" bus data to get the minimun AC voltage to pin (39) of IC3001. SIGNAL 1: SIGNAL 2: 3kHz, 30% modulation, Lch only, NR-ON

Note: SIGNAL 1 Adj. for widebando

SIGNAL 2 Adj. for spectral Check the output of the speaker at the maximum volume as stated below. Confirmation spec:

ADJ spec: above 25 dB

CHK spec: above 20 dB

300Hz, 30% modulation, Lch only, NR-ON

27UC4

P-IN-P ADJUSTMENT

P-IN-P Y -LEVEL Adjustment

1. Receive a good local channel.

2. Enter the service mode and select the service adjustment "P01".

3. Adjust "P01" data value to obtain normal contrast level.

P-IN-P TINT Adjustment

1. Receive a good local channel.

2. Enter the service mode and select the service adjustment "P02".

3. Adjust data value to "29h".

P-IN-P COLOR Adjustment

1. Receive a good local channel.

2. Make sure the customer color control is set to center position.

3. Enter the service mode and select the service adjustment "P03".

4. Adjust "P03" data value to obtain normal color level.

P-IN-P Y -OFF SET Adjustment

1. Receive a good local channel.

2. Enter the service mode and select the service adjustment "P04".

3. Adjust data value to "09h".

P-IN-P H-POSITION Adjustment

1. Receive a good local channel.

2. Enter the service mode and select the service adjustment "P05".

3. Adjust data value to "0Ah".

P-IN-P BURST GATE PULSE (for MAIN)

1. Receive a good local channel.

2. Enter the service mode and select the service adjustment "P06".

3. Adjust data value to "00h".

P-IN-P FREERUN

1. Receive a good local channel.

2. Enter the service mode and select the service adjustment "P07".

3. Adjust data value to "0Bh".

P-IN-P TINT INPUT Adjustment

1. Receive an AV/Component input signal.

2. Enter the service mode and select the service adjustment "P08".

3. Adjust data value to "24h".

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