JVC AV-14F702 Service Manual

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SER VICE MANUAL

COLOUR TELEVISION

AV-14F702

V-14F702

CONTENTS

SPECIFICATIONS

★

OPERATING INSTRUCTIONS (APPENDED) SAFETY PRECAUTIONS

SPECIFIC SERVICE INSTRUCTIONS

SERVICE ADJUSTMENTS

GUIDE FOR REP AIRIN G

★

STANDARD CIRCUIT DIAGRAM (APPENDED) PARTS LIST

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No. 51912 Nov. 2001

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AV-14F702

SPECIFICATIONS

Items Contents

Dimensions (W Mass TV System and Color system

TV RF System Color System

TV Receiving Channels and Frequency

VHF UHF CATV

TV/CATV Total Channel Intermediate Frequency

Video IF Carrier

Sound IF Carrier Color Sub Carrier Power Input Power Consumption Picture Tube Speaker Audio Power Output Input (1 / 2 /3)

Component Input

Antenna te rminal Remote Control Unit

××××H××××

43.2cm×34.45cm×39.35cm

26.4Ibs

CCIR(M) NTSC

2-13 14-69 01-97 (5A)-(A-3) 98-99 (A-2)-(A-1) 14-22 (A)-(I) 23-36 (J)-(W) 37-65 (AA)-(FFF) 66-125 (GGG)-(125) 180 Channels

45.75 MHz

41.25 MHz (4.5MHz)

3.58 MHz 120V AC, 60Hz 80W 14” 1-3/5" x 2-4/5", 8 ohm x 2

2.5 W + 2.5 W Video : 1Vp-p 75ohm (RCA pin jack) Audio : –8dB, 47kohm (RCA pin jack) S-Video Y : 1.0Vp-p, 75 ohm

C : 0.3Vp-p, 75 ohm Y: 1.0Vp-p, 75 ohm PB: 0.7Vp-p, 75 ohm PR: 0.7Vp-p, 75 ohm 75Ω (VHF/UHF) Terminal, F-Type Connector RM-C309G

Design & specification are subject to c hange without not ic e.

No.51912

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SAFETY PRECAUTIONS

SERVICING NOTICES ON CHECKING

As for the places which need special attentions, they are indicated with the labels or seals on the cabinet, chassis and parts. Make sure to keep the indications and notices in the operation manual.

2. AVOID AN ELECTRIC SHOCK

There is a high voltage part inside. Avoid an electric shock while the electric current is flowing.

3. USE THE DESIGNATED PARTS

The parts in this equipment have the specific characters of incombustibility and withstand voltage for safety. Therefore, the part which is replaced should be used the part which has the same character. Especially as to the important parts for safety which is indicated in the circuit diagram or the table of parts as a mark, the designated parts must be used.

4. PUT PARTS AND WIRES IN THE ORIGINAL POSITION AFTER ASSEMBLING OR WIRING

There are parts which use the insulation material such as a tube or tape for safety, or which are assembled in the condition that these do not contact with the printed board. The inside wiring is designed not to get closer to the pyrogenic parts and high voltage parts. Therefore, put these parts in the original positions.

5. TAKE CARE TO DEAL WITH THE CATHODE-RAY TUBE

In the condition that an explosion-proof cathoderay tube is set in this equipment, safety is secured against implosion. However, when removing it or serving from backward, it is dangerous to give a shock. Take enough care to deal with it.

6. AVOID AN X-RAY1. KEEP THE NOTICES

Safety is secured against an X-ray by considering about the cathode-ray tube and the high voltage peripheral circuit, etc. Therefore, when repairing the high voltage peripheral circuit, use the designated parts and make sure not modify the circuit. Repairing except indicates causes rising of high voltage, and it emits an X-ray from the cathoderay tube.

PERFORM A SAFETY CHECK AFTER

7. SERVICING

Confirm that the screws, parts and wiring which were removed in order to service are put in the original positions, or whether there are the portions which are deteriorated around the serviced places serviced or not. Check the insulation between the antenna terminal or external metal and the AC cord plug blades. And be sure the safety of that.

(INSULATION CHECK PROCEDURE)

Unplug the plug from the AC outlet.

Remove the antenna terminal on TV and turn on the TV.

Insulation resistance between the cord plug terminals and the eternal exposure metal [Note 2] should be more than 1M ohm by using the 500V insulation resistance meter [Note 1].

If the insulation resistance is less than 1M ohm, the inspection repair should be required.

[Note 1]

If you have not the 500V insulation resistance meter, use a Tester.

[Note 2]

External exposure metal: Antenna terminal

Earphone jack

AV-14F702

HOW TO ORDER PARTS

Please include the following informations when you order parts. (Particularly the VERSION LETTER.)

1. MODEL NUMBER and VERSION LETTER The MODEL NUMBER can be found on the back of each product and the VERSION LETTER can be

found at the end of the SERIAL NUMBER.

2. PART NO. and DESCRIPTION You can find it in your SERVICE MANUAL.

IMPORTANT

Inferior silicon grease can damage IC's and transistors. When replacing an IC's or transistors, use only specified silicon grease (YG6260M). Remove all old silicon before applying new silicon.

Licensed by BBE Sound, Inc. under USP4638258 and 4482866. BBE and BBE symbol are registered trademarks of BBE Sound, Inc.

No.51912 3

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AV-14F702

SPECIFIC SERVICE INSTRUCTIONS

DISASSEMBLY INSTRUCTIONS

1. REMOVAL OF ANODE CAP

Read the following NOTED items before starting work. *

After turning the power off there might still be a potential voltage that is very dangerous. When removing the Anode Cap, make sure to discharge the Anode Cap's potential voltage.

Do not use pliers to loosen or tighten the Anode Cap terminal, this may cause the spring to be damaged.

REMOVAL

1. Follow the steps as follows to discharge the Anode Cap.

(Refer to Fig. 1-1.)

Connect one end of an Alligator Clip to the metal part of a flat-blade screwdriver and the other end to ground. While holding the plastic part of the insulated Screwdriver, touch the support of the Anode with the tip of the Screwdriver. A cracking noise will be heard as the voltage is discharged.

GND on the CRT

3. After one side is removed, pull in the opposite direction to remove the other.

NOTE

Take care not to damage the Rubber Cap.

INSTALLATION

1. Clean the spot where the cap was located with a small amount of alcohol. (Refer to Fig. 1-3.)

Location of Anode Cap

Fig. 1-3

NOTE

Confirm that there is no dirt, dust, etc. at the spot where the cap was located.

2.3.Arrange the wire of the Anode Cap and make sure the wire is not twisted. Turn over the Rubber Cap. (Refer to Fig. 1-4.)

Screwdriver

Alligator Clip

GND on the CRT

Flip up the sides of the Rubber Cap in the direction of the

2. arrow and remove one side of the support.

(Refer to Fig. 1-2.)

Rubber Cap

CRT

Support

CRT

Fig. 1-1

Fig. 1-2

Fig. 1-4

4. Insert one end of the Anode Support into the anode button, then the other as shown in Fig. 1-5.

Support

CRT

5.6.Confirm that the Support is securely connected. Put on the Rubber Cap without moving any parts.

Fig. 1-5

No.519124

Page 5

DISASSEMBLY INSTRUCTIONS

REMOVAL AND INSTALLATION OF FLAT PACKAGE IC

REMOVAL

Put the Masking Tape (cotton tape) around the Flat

1. Package IC to protect other parts from any damage.

(Refer to Fig. 2-1.) NOTE

Masking is carried out on all the parts located within 10 mm distance from IC leads.

When IC starts moving back and forth easily after

3. desoldering completely, pickup the corner of the IC using a tweezers and remove the IC by moving with the IC desoldering machine. (Refer to Fig. 2-3.)

NOTE

Some ICs on the PCB are affixed with glue, so be careful not to break or damage the foil of each IC leads or solder lands under the IC when removing it.

Blower type IC desoldering machine

AV-14F702

Masking Tape (Cotton Tape)

Heat the IC leads using a blower type IC desoldering

machine. (Refer to Fig. 2-2.)

NOTE

Do not add the rotating and the back and forth directions force on the IC, until IC can move back and forth easily after desoldering the IC leads completely.

Blower type IC desoldering machine

Fig. 2-1

Tweezers

Peel off the Masking Tape.4. Absorb the solder left on the pattern using the Braided

5. Shield Wire. (Refer to Fig. 2-4.)

NOTE

Do not move the Braided Shield Wire in the vertical direction towards the IC pattern.

Fig. 2-3

Braided Shield Wire

Soldering Iron

Fig. 2-2

IC pattern

Fig. 2-4

No.51912 5

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AV-14F702

DISASSEMBLY INSTRUCTIONS

INSTALLATION

Take care of the polarity of new IC and then install the

1. new IC fitting on the printed circuit pattern. Then solder each lead on the diagonal positions of IC temporarily.

(Refer to Fig. 2-5.)

Soldering Iron

Solder temporarily

Supply the solder from the upper position of IC leads

Solder temporarily

sliding to the lower position of the IC leads. (Refer to Fig. 2-6.)

Fig. 2-5

When bridge-soldering between terminals and/or the

4. soldering amount are not enough, resolder using a Thintip Soldering Iron. (Refer to Fig. 2-8.)

Thin-tip Soldering Iron

Fig. 2-8

Finally, confirm the soldering status on four sides of the

5. IC using a magnifying glass. Confirm that no abnormality is found on the soldering position and installation position of the parts around the IC. If some abnormality is found, correct by resoldering.

NOTE

When the IC leads are bent during soldering and/or repairing, do not repair the bending of leads. If the bending of leads are repaired, the pattern may be damaged. So, be always sure to replace the IC in this case.

Soldering IronSolder

Absorb the solder left on the lead using the Braided

Supply soldering from upper position to lower position

Shield Wire. (Refer to Fig. 2-7.)

NOTE

Do not absorb the solder to excess.

Soldering Iron

Braided Shield Wire

Fig. 2-6

Fig. 2-7

No.519126

Page 7

SERVICE MODE LIST

This unit provided with the following SERVICE MODES so you can repair, examine and adjust easily. To enter the Service Mode, press both set key and remote control key for more than 1 second.

Set Key Remocon Key Operations

VOL. (-) MIN VOL. (-) MIN 1

VOL. (-) MIN 6

Releasing of V-CHIP PASSWORD. Initialization of the factory.

NOTE: Do not use this for the normal servicing. POWER ON total hours is displayed on the screen.

Refer to the "CONFIRMATION OF USING HOURS". Can be checked of the INITIAL DATA of MEMORY IC.

Refer to the "NOTE FOR THE REPLACING OF MEMORY IC".

AV-14F702

VOL. (-) MIN 8

VOL. (-) MIN

Writing of EEPROM initial data. NOTE: Do not use this for the normal servicing.

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

CONFIRMATION OF USING HOURS

POWER ON total hours can be checked on the screen. Total hours are displayed in 16 system of notation.

Set the VOLUME to minimum.

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

After the confirmation of using hours, turn off the power.

ADDRESS DATA

INIT 00 83 CRT ON

0010

FIG. 1

Initial setting content of MEMORY IC. 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)

NOTE FOR THE REPLACING OF 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.

+0 +1 +2 +3 +4 +5 +6 +7 +8 +9 E1 C3 02 00 31 B3 AF 37 9F A8

00 FF 04 00 00 00 4A

0F --- --- --- --- --- --- --- ---

---

+B +C +D +E +FINI

--- --- --- --- --- ---

Table 1

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 1 second.

2. ADDRESS and DATA should appear as FIG 1. ADDRESS is now selected and should "blink". Using the VOL. UP/DOWN button on the remote, step through the

3. ADDRESS until required ADDRESS to be changed is reached. Press ENTER to select DATA. When DATA is selected, it will "blink".

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

5. Pressing ENTER will take you back to ADDRESS for further selection if necessary.

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

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

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

No.51912 7

Page 8

AV-14F702

SERVICE ADJUSTMENT

ELECTRICAL ADJUSTMENTS

BEFORE MAKING ELECTRICAL ADJUSTMENTS

Read and perform these adjustments when repairing the 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. Inferior silicon grease can damage IC's and transistors.

•

When replacing IC's and transistors, use only specified silicon grease. Remove all old silicon before applying new silicon.

Prepare the following measurement tools for electrical adjustments.

1. Oscilloscope

2. Digital Voltmeter

On-Screen Display Adjustment

In the condition of NO indication on the screen.

1. Press the VOL. DOWN button on the set and the Channel button (9) on the remote control for more than 1 second to appear the adjustment mode on the screen as shown in Fig. 1-1.

00 OSD 15

Fig. 1-1

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 adjustments.

2. BASIC ADJUSTMENTS

2-1: CONSTANT VOLTAGE

Set condition is AV MODE without signal.

Connect the digital voltmeter to TP002.

Adjust the VR502 until the digital voltmeter is 115 ± 1V.

2-2: RF AGC

Receive a 63dB monoscope pattern.

Connect the digital voltmeter between the TP001 and the GND.

Activate the adjustment mode display of Fig. 1-1 and press the channel button (02) on the remote control to select "RF. AGC".

Press the VOL. UP/DOWN button on the remote control until the digital voltmeter is 2.50 ± 0.05V.

2-3: CUT OFF

Adjust the unit to the following settings. G. DRIVE=64, B. DRIVE=64, R. BIAS=32, G. BIAS=32, B. BIAS=32, BRIGHTNESS=64, UNI COLOR=50.

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

Activate the adjustment mode display of Fig. 1-1 and press the channel button (01) on the remote control to select "CUT OFF".

Adjust the Screen Volume until a dim raster is obtained.

2-4: WHITE BALANCE NOTE: Adjust after performing CUT OFF adjustment.

Place the set with Aging Test for more than 10 minutes.

Receive the white 100% signal from the Pattern 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 (13) 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 "G. DRV", "B. DRV", "G. BIAS" or "B. BIAS".

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

Perform the above adjustments 6 and 7 until the white color is looked like a white.

NO.

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

FUNCTION

OSD H CUT OFF RF. AGC

--H. POSI V. POSI H. SIZE V. SIZE V. CENT V. LIN VS. CORR G. DRV B. DRV R. BIAS G. BIAS B. BIAS BRI

NO.

17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33

FUNCTION

SUBCONT UNI COL

--TINT SHARP RGB CONT PARABOLA TRAPEZIU COR TOP COR BTM V EHT H EHT FM. LVL LEVEL SEP1 SEP2 T. STE

Fig. 1-2

2-5: FOCUS

Receive a 70dB monoscope pattern.

Turn the Focus Volume fully counterclockwise once.

Adjust the Focus Volume until picture is distinct.

2-6: HORIZONTAL POSITION

Receive the center cross 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 (04) on the remote control to select "H. POSI".

Press the VOL. UP/DOWN button on the remote control until the right and left screen size of the vertical line becomes the same.

No.519128

Page 9

ELECTRICAL ADJUSTMENTS

AV-14F702

2-7: HORIZONTAL SIZE NOTE: Adjust after performing adjustments in section 2-6.

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 "H. SIZE".

Press the VOL. UP/DOWN button on the remote control until the SHIFT quantity of the OVER SCAN on right and left becomes 10 ± 2%.

2-8: VERTICAL POSITION NOTE: Adjust after performing adjustments in section 2-7.

Receive the center cross signal from the Pattern Generator.

Activate the adjustment mode display of Fig. 1-1 and press the channel button (05) on the remote control to select "V. POSI".

Press the VOL. UP/DOWN button on the remote control until the horizontal line becomes fit to the notch of the shadow mask.

2-9: VERTICAL SIZE NOTE: Adjust after performing adjustments in section 2-8.

Receive the crosshatch signal from the Pattern Generator.

Activate the adjustment mode display of Fig. 1-1 and press the channel button (07) on the remote control to select "V. SIZE".

Press the VOL. UP/DOWN button on the remote control until the rectangle on the center of the screen becomes square.

Receive a broadcast and check if the picture is normal.

2-12: CORNER CORR TOP

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 (25) on the remote control to select "COR TOP".

Press the VOL. UP/DOWN button on the remote control until the upper section of the both ends vertical lines are straight.

2-13: CORNER CORR BOTTOM

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 (26) on the remote control to select "COR BTM".

Press the VOL. UP/DOWN button on the remote control until the bottom section of the both ends vertical lines are straight.

2-14: OSD HORIZONTAL

1.2.Activate the adjustment mode display of Fig. 1-1. Press the VOL. UP/DOWN button on the remote control until the difference of A and B becomes minimum.

(Refer to Fig. 2-1)

2-10: PARABOLA CORR

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 (23) on the remote control to select "PARABOLA".

Press the VOL. UP/DOWN button on the remote control until the right and left vertical lines are straight.

2-11: TRAPEZIUM DIS

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 (24) on the remote control to select "TRAPEZIU".

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

00 OSD 15

2-15: LEVEL

Receive a 70dB monoscope pattern.

Connect the AC voltmeter to TP901.

Activate the adjustment mode display of Fig. 1-1 and press the channel button (30) on the remote control to select "LEVEL".

Press the VOL. UP/DOWN button on the remote control until the AC voltmeter is 75 ± 2mV.

Fig. 2-1

No.51912 9

Page 10

AV-14F702

ELECTRICAL ADJUSTMENTS

2-16: SEPARATION 1, 2

Receive the stereo signal (L=2KHz, R=400Hz).

1. Connect the AC voltmeter to AUDIO OUT JACK though

2. stereo filter (L=400Hz, R=2KHz). Activate the adjustment mode display of Fig. 1-1 and

3. press the channel button (31) on the remote control to select "SEP1". Press the VOL. UP/DOWN button on the remote control

4. until the output of L-CH and R-CH become minimum. Press the CH UP button once the set to "SEP2" mode.

5. Press the VOL. UP/DOWN button on the remote control

6. until the output of L-CH and R-CH become minimum. Press the CH DOWN button once the set to "SEP1"

7. mode. Repeat step 4 to step 7 several times.

8. The output difference of the between with Filter and without Filter should be more than 25dB for both L and R.

2-17: BRIGHTNESS

Activate the adjustment mode display of Fig. 1-1 and press the channel button (16) on the remote control to select "BRI".

Press the VOL. UP/DOWN button on the remote control until the brightness step No. becomes "71".

Press the INPUT button on the remote control to set to the AV mode.

Activate the adjustment mode display of Fig. 1-1 and press the channel button (16) on the remote control to select "BRI".

Press the VOL. UP/DOWN button on the remote control until the brightness step No. becomes "69".

Press the INPUT button on the remote control to set to the CS mode.

Activate the adjustment mode display of Fig. 1-1 and press the channel button (16) on the remote control to select "BRI".

Press the VOL. UP/DOWN button on the remote control until the brightness step No. becomes "64".

2-20: SUB TINT/SUB COLOR

Receive the color bar pattern. (RF Input)

Connect the oscilloscope to TP806.

Activate the adjustment mode display of Fig. 1-1 and press the channel button (20) on the remote control to select "TINT".

Press the VOL. UP/DOWN button on the remote control until the section "A" becomes a straight line (Refer Fig. 2-2).

Connect the oscilloscope to TP804.

Press the CH DOWN button 3 times to set to "SUBCONT" mode.

Press the VOL. UP/DOWN button on the remote control until the red color level is adjusted to 115% of the white level. (Refer to Fig. 2-3)

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 2~7.

10.

Press the INPUT button on the remote control to set to the CS mode.

11.

Activate the adjustment mode display of Fig. 1-1 and press the channel button (20) on the remote control to select "TINT".

12.

Press the VOL. UP/DOWN button on the remote control to increase the step numbers by 6 steps to the AV.

13.

Press the CH DOWN button 3 times to set to "SUBCONT" mode.

14.

Press the VOL. UP/DOWN button on the remote control to set the same step number as the AV.

2-18: UNI-COLOR

Activate the adjustment mode display of Fig. 1-1 and press the channel button (18) on the remote control to select "UNI COL".

Press the VOL. UP/DOWN button on the remote control until the contrast step No. becomes "50".

Press the INPUT button on the remote control to set to the AV mode. Then perform the above adjustments 1,2.

Press the INPUT button on the remote control to set to the CS mode.

Activate the adjustment mode display of Fig. 1-1 and press the channel button (18) on the remote control to select "UNI COL".

Press the VOL. UP/DOWN button on the remote control until the contrast step No. becomes "54".

2-19: VERTICAL LINEARITY

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 (09) 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.

"A" "A"

Fig. 2-2

White 100%

RED Level

Fig. 2-3

No.5191210

Page 11

ELECTRICAL ADJUSTMENTS

AV-14F702

PURITY AND CONVERGENCE ADJUSTMENTS

NOTE

Turn the unit on and let it warm up for at least 30 minutes before performing the following adjustments.

Place the CRT surface facing east or west to reduce the terrestrial magnetism.

Turn ON the unit and demagnetize with a Degauss Coil.

3-1: STATIC CONVERGENCE (ROUGH ADJUSTMENT)

Tighten the screw for the magnet. Refer to the adjusted CRT for the position. (Refer to Fig. 3-1) If the deflection yoke and magnet are in one body, untighten the screw for the body.

Receive the green raster pattern from the color bar generator.

Slide the deflection yoke until it touches the funnel side of the CRT.

Adjust center of screen to green, with red and blue on the sides, using the pair of purity magnets.

Switch the color bar generator from the green raster pattern to the crosshatch pattern.

Combine red and blue of the 3 color crosshatch pattern on the center of the screen by adjusting the pair of 4 pole magnets.

Combine red/blue (magenta) and green by adjusting the pair of 6 pole magnets.

Adjust the crosshatch pattern to change to white by repeating steps 6 and 7.

3-2: PURITY NOTE

Adjust after performing adjustments in section 3-1.

Receive the green raster pattern from color bar generator.

Adjust the pair of purity magnets to center the color on the screen. Adjust the pair of purity magnets so the color at the ends are equally wide.

Move the deflection yoke backward (to neck side) slowly, and stop it at the position when the whole screen is green.

Confirm red and blue colors.

Adjust the slant of the deflection yoke while watching the screen, then tighten the fixing screw.

DEFLECTION YOKE DEFLECTION YOKE SCREW MAGNET SCREW

3-3: STATIC CONVERGENCE NOTE

Adjust after performing adjustments in section 3-2.

Receive the crosshatch pattern from the color bar generator.

Combine red and blue of the 3 color crosshatch pattern on the center of the screen by adjusting the pair of 4 pole magnets.

Combine red/blue (magenta) and green by adjusting the pair of 6 pole magnets.

3-4: DYNAMIC CONVERGENCE

NOTE

Adjust after performing adjustments in section 3-3.

1.2.Adjust the differences around the screen by moving the deflection yoke upward/downward and right/left.

(Refer to Fig. 3-2-a)

Insert three wedges between the deflection yoke and CRT funnel to fix the deflection yoke.

(Refer to Fig. 3-2-b)

R G B

UPWARD/DOWNWARD SLANT RIGHT/LEFT SLANT

WEDGE

WEDGE POSITION

R G B

Fig. 3-2-a

WEDGE

Fig. 3-2-b

R G B

Fig. 3-1

PURITY MAGNETS 6 POLE MAGNETS

4 POLE MAGNETS

No.51912 11

Page 12

AV-14F702

MAJOR COMPONENTS LOCATION GUIDE

VR502

T501

TP002

TP001

TP901

TU001

J702

J701

J703

TP806

J704

J705

FB401

FOCUS VOLUME SCREEN VOLUME

MAIN PCB

J801

TP804

CRT PCB

No.5191212

Page 13

GUIDE FOR REPAIRING

IC DESCRIPTION

SYSCON PCB OEC7055B(IC101)

NO. Symbol I/O Logi c Func tion Option

1 H.SY NC Input 0 Horizontal synchronization input 2 V. SYNC I n put 0 Ve r tica l sync hron i za t i o n i nput 3 - Input - Unused 4 REMOCON Input - Remote control input 5 - Input - Unused 6 SYNC Input - Synchronization detector input 7 KE Y1 I npu t - Vo lt ag e of th e TV butt on in put( po we r, vol do wn,c h do wn) C- M OS 8 KE Y2 I npu t - Vo lt ag e of th e TV butt on in put( vol up ,ch up ) C- M OS

9 X - RA Y I npu t - X - RA Y de tect or in put C- M OS 10 AFT I n put - Vo l ta g e of tu ning i n pu t C-MOS 11 - Input - Unused N-OD 12 - Input - Unused N-OD 13 - Input - Unused N-OD 14 - Output - Unused C-MOS 15 PO WE R FA IL I npu t 0 Powe r fa i l ur e dete ct or in put 16 - Input - Unused N-OD 17 - Input - Unused N-OD 18 AVCC - - Positive power supply for analog block (5v nom,) 19 HLF - - Fi lter for CCD 20 RVCO - - Resist or for CCD 21 VHO LD - - Capacit y for CCD 22 CV I N I - Vi deo si gn al for CC D 23 CNVSS - - Negative power supply for anal og bl ock (ground) 24 XI N Input - Ma in Oscillat ion (8MH z) 25 XO U T Ou tp ut - M ain Os c illat i o n ( 8 MHz) 26 VS S - - Nega ti ve po we r su pply for di gi ta l bl oc k ( gr oun d) 27 VC C - - Posi ti ve pow er supply for di gi ta l bl oc k (5 v nom, ) 28 OSC1 - In put Osci ll a tion for OSD 29 OSC2 - Output Oscillation for OSD 30 RESET Input 0 Reset signal input 31 AV 1 O - Ex t e r n al SW out o pu t1 C-MOS 32 AV 2 O - Ex t e r n al SW out o pu t2 C-MOS 33 ON TIMER O 1 On tim e r LED outp ut C-MOS 34 DE G AU SS H O 1 De ga uss ou tp ut C- M OS 35 SP OT OFF O 0 Sp ot killer ou tp ut C-MOS 36 - I - Unused N-OD 37 SDA I /O 1 Se r ia l data in pu t / ou t p ut N -OD 38 - I - Unused N-OD 39 SCL O 1 Se r ia l clock ou t p ut N-OD 40 HALF T ONE O 1 Half t o ne outp ut C -MO S 41 PO WE R O 1 Po wer cont ro l ou tput C- MO S 42 COMP H O 1 Component output C-MOS

AV-14F702

No.51912 13

Page 14

AV-14F702

IC DESCRIPTION

SYSCON PCB OEC7055B(IC101)

NO. Symbol I/O Logi c Func tion Option

43 I IC O FF I 0 Ser ial cloc k/data stop inpu t C-MOS 44 BB E H O 1 BBE c ont ro l ou tput C- M OS 45 TV MUTE O 0 Vo l u m e m u t ing ou tput fo r l ouds p eake r N-OD 46 EXT M UTE O 1 Vo l u m e m u t ing ou tp ut fo r exte r nal N-OD 47 - O - Unused N-OD 48 X RAY TEST O 1 X-RAY test output N-OD 49 BL O 1 Fa st blanking control signal C-MOS 50 B O 1 Bl ue out p ut of OS D C-MOS 51 G O 1 Green outp ut of OS D C-MOS 52 R O 1 Re d out p ut of OS D C-MOS

No.5191214

Page 15

NO POWER

AV-14F702

TROUBLESHOOTING GUIDE

Is the voltage at C501 DC24.0V ?

Is the voltage at pin 4 of IC501 DC18V ?

Is the voltage at the point A in the Figure DC170V ?

Is the voltage at the point B in the Figure AC120V ?

Is the voltage at the point C in the Figure AC120V ?

Yes

Check the circuit after C501.

Check IC501 and associated circuit.

Broken wire of R501 or short circuit on GND.

Check D501 ~ D504 rectifying circuit.

Broken wire of L501.

IC501

T501

R501

D501~D504

L501

Is the voltage on both ends of CP501 AC120V ?

Broken wire of AC cord or check CP501.

Yes

F501

Broken wire of F501.

CP501

CD501

No.51912 15

Page 16

AV-14F702

TROUBLESHOOTING GUIDE

NO RASTER

Does the RASTER appear at maximum BRIGHT/CONTRAST ?

Is the high voltage of ANODE 32KV ?

Is collector voltages of Q405 DC2.8V and Q402 DC17.3V ?

Yes

Is the voltage of pin 1 of CP801 DC180V ?

Check the 180V line.

Is the heater voltage at pin 10 of J801 AC6.3V ?

Check the HEATER circuit.

Yes

Check the output circuit and associated circuit.

Contact defects of CRT or CRT Socket.

Check FB401 and associated circuit.

Is the waveform at base of Q405 normal ?

Is the waveform at pin 34 of IC201 normal ?

Check IC201 and associated circuit.

Yes

Broken wire of R439.

Check the circuit from pin 34 of IC201 to Q402.

No.5191216

Page 17

NO COLOR

AV-14F702

TROUBLESHOOTING GUIDE

Are the waveforms at pins 3, 7 and 9 of J801 normal ?

Are the waveforms at pins 4, 5 and 6 of CP802 normal ?

Are the waveforms at pins 14, 15 and 16 of IC201 normal ?

Is the pulse of crystal X601 normal ?

Yes

Defect of CRT or contact defects of J801.

Check the output circuit and associated circuit.

Check Q801, 802, Q803 and peripheral circuit.

Check the associated circuit of IC201.

Check X601.

No.51912 17

Page 18

AV-14F702

TROUBLESHOOTING GUIDE

NO VERTICAL

Is the waveform at pin 6 of CP401 normal ?

Is the waveform at pin 5 of IC401 normal ?

Is the voltage pin 2 of IC401 DC 25v ?

Broken wire of R431.

Yes

Is the waveform at pin 1 of IC401 normal ?

Check IC201 and peripheral circuit.

Yes

Check DY.

Check the circuit from pin 5 of IC401 to CP401.

Check IC401 and peripheral circuit.

No.5191218

Page 19

NO SOUND

Is sound setting appropriate ?

Yes

AV-14F702

TROUBLESHOOTING GUIDE

Is the audio signal pins 7 and 12 of IC353?

Is the audio signal pins 2 and 5 of IC353?

Is the audio signal pins 7 and 14 of IC303?

Check the CHROMA IC, AV SW IC and peripheral circuit.

Yes

Check SPEAKER.

Replace IC353 and check peripheral

circuit.

Check IC303 and peripheral circuit.

No.51912 19

Page 20

AV-14F702

TROUBLESHOOTING GUIDE

NO CCD

Does pin 22 of IC101 contain VIDEO signal ?

Yes

Is the Voltage pin 27 of IC101 DC 5v?

Yes

Does pin 1 of IC101 contain waveform ?

Yes

Defects on IC101.

Does pin 25 of IC701 feed VIDEO signal ?

Yes

Check the circuit from pin 22 of IC101.

Check the associated circuit of IC701.

Check the circuit from Q501 and IC503.

Check the circuit from pin 1 of IC101 to pin 9 of FB401.

No.5191220