JVC AV-14F704 Schematic

SERVICE MANUAL

COLOR TELEVISION

AV-14F704

VOL

CONTENTS

q SPECIFICATIONS.............................................................................................................................................. 2

q OPERATING INSTRUCTIONS (APPENDIX)

q SAFETY PRECAUTIONS .................................................................................................................................. 3

q SPECIFIC SERVICE INSTRUCTIONS .............................................................................................................. 4

q SERVICE ADJUSTMENTS ................................................................................................................................ 8

q GUIDE FOR REPAIRING ................................................................................................................................. 13

q STANDARD CIRCUIT DIAGRAM ................................................................................................................... 2-1

q PARTS LIST ..................................................................................................................................................... 19

No. 52130

2003/05

AV-14F704

SPECIFICATIONS

TELEVISION

Picture Tube: 14” (measured diagonally)

Color System: NTSC

TV RF System: US System M

Tuner Type: 181 Channel, Quartz PLL Frequency Synthesized

Receiving Channels: VHF 2-13

UHF 14-69

CATV 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)

Intermediate Frequency: Picture (FP) : 45.75 MHz

Sound (FS) : 41.25 MHz

FP-FS : 4.50 MHz

Antenna Input: VHF/UHF/CATV In 75 ohms coaxial, F-Type Connector

Speaker: 1-5/8” (4 cm) x 2-13/16” (7 cm), 8 ohms x 2

Audio Output Power: 2.5 W + 2.5 W

GENERAL

Power Source: 120 V AC, 60 Hz

Power Consumption: 80 Watts

Dimensions(W x H x D): 17-1/8” (432 mm) x 13-5/8” (344.5 mm) x 15-1/2” (393.5 mm)

Weight: 26.4 Ibs/12 kg

Video/Audio Inputs: Component input

Y input: 1.0 Vp-p, 75 ohm (RCA pin jack)

Pb, Pr input : 0.7 Vp-p, 75 ohm (RCA pin jack)

S-Video input

Y input: 1.0 Vp-p, 75 ohm

C input: 0.3 Vp-p, 75 ohm

Video input: 1.0 Vp-p, 75 ohm (RCA pin jack)

Audio input: -8dB, 47 kohm (RCA pin jack)

Headphone Jack: 3.5 mm mini-jack

Storage Temperature -20 ºC ~ 60 ºC

Operating Temperature 5 ºC ~ 40 ºC

Accessories:

Remote Control X 1

Batteries (UM-3) X 2

Design & specification are subject to change without notice.

No. 52130

SAFETY PRECAUTIONS

SERVICING NOTICES ON CHECKING

AV-14F704

1. KEEP THE NOTICES

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-RAY

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.

7. PERFORM A SAFETY CHECK AFTER 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)

1. Unplug the plug from the AC outlet.

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

3. 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].

4. 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

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.

No. 52130

AV-14F704

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 flatblade 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.)

NOTE

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

Location of Anode Cap

Fig. 1-3

2. Arrange the wire of the Anode Cap and make sure the wire is not twisted.

3. Turn over the Rubber Cap. (Refer to Fig. 1-4.)

Screwdriver

Support

CRT

Alligator Clip

GND on the CRT

2. Flip up the sides of the Rubber Cap in the direction of the arrow and remove one side of the support.

(Refer to Fig. 1-2.)

Fig. 1-1

Rubber Cap

CRT

Support

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. Confirm that the Support is securely connected.

6. Put on the Rubber Cap without moving any parts.

Fig. 1-5

No. 52130

AV-14F704

2. REMOVAL AND INSTALLATION OF FLAT PACKAGE IC

REMOVAL

1. Put the Masking Tape (cotton tape) around the Flat 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.

Masking Tape (Cotton Tape)

2. 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.

Fig. 2-1

Blower type IC desoldering machine

3. When IC starts moving back and forth easily after 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

Tweezers

Fig. 2-3

4. Peel off the Masking Tape.

5. Absorb the solder left on the pattern using the Braided Shield Wire. (Refer to Fig. 2-4.)

NOTE

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

Braided Shield Wire

Soldering Iron

Fig. 2-2

No. 52130

IC pattern

Fig. 2-4

AV-14F704

INSTALLATION

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

Fig. 2-5

2. Supply the solder from the upper position of IC leads sliding to the lower position of the IC leads.

(Refer to Fig. 2-6.)

4. When bridge-soldering between terminals and/or the soldering amount are not enough, resolder using a Thintip Soldering Iron.

(Refer to Fig. 2-8.)

Thin-tip Soldering Iron

Fig. 2-8

5. Finally, confirm the soldering status on four sides of the 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.

Solder

Supply soldering from upper position to lower position

Soldering Iron

Fig. 2-6

3. Absorb the solder left on the lead using the Braided Shield Wire.

(Refer to Fig. 2-7.)

NOTE

Do not absorb the solder to excess.

Soldering Iron

Braided Shield Wire

Fig. 2-7

No. 52130

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

Releasing of V-CHIP PASSWORD.

Initialization of the factory.

NOTE: Do not use this for the normal servicing.

If you set a factory initialization, the memories are reset such as the channel setting, and

the POWER ON total hours.

Remocon format selection. (JVC format → NEC format)

NOTE: Supplied remocon can not be operated at NEC format.

(The “N” is always displayed on the monitor.)

Do not use this for the normal servicing.

POWER ON total hours is displayed on the screen.

Refer to the “CONFIRMATION OF HOURS USED”.

Can be checked of the INITIAL DATA of MEMORY IC.

Refer to the “WHEN REPLACING EEPROM (MEMORY) IC”.

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).

AV-14F704

CONFIRMATION OF HOURS USED

POWER ON total hours 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”.

1. Set the VOLUME to minimum.

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

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

ADDRESS DATA

INIT 00 D0

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)

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.

NOTE: No need setting for after INI 1F due to the adjustment value.

INI

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

D0 E8 02 64 5E B3 24 37 39 AC

00 00 04 40 40 40 7F

50 00 00 00 16 06 99 28 0F10 00 0D C2 A6 88 43 00

Table 1

1. Enter DATA SET mode by setting VOLUME to minimum.

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

ADDRESS and DATA should appear as FIG 1.

3. ADDRESS is now selected and should “blink”. Using the VOL. +/- button on the remote, step through the ADDRESS until required

ADDRESS to be changed is reached.

4. Press ENTER to select DATA. When DATA is selected, it will “blink”.

5. Again, step through the DATA using VOL. +/- button until required DATA value has been selected.

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

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

8. 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.

9. Turn on the POWER.

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

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

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

No. 52130

AV-14F704

SERVICE ADJUSTMENTS

ELECTRICAL ADJUSTMENTS

1. ADJUSTMENT PROCEDURE

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.

•When you exchange IC and Transistor for a heat sink, apply the 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 Signal 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 1 second to appear the adjustment mode on the screen as shown in Fig. 1-1.

2. BASIC ADJUSTMENTS

2-1: CONSTANT VOLTAGE

1. Place the set with Aging Test for more than 5 minutes.

2. Set condition is AV MODE without signal.

3. Connect the digital voltmeter to the TP003.

4. Adjust the VR502 until the DC voltage is 115 ± 1V.

2-2: CUT OFF

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

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

3. Adjust the Screen Volume until a dim raster is obtained.

2-3: WHITE BALANCE

NOTE: Adjust after performing CUT OFF adjustment.

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

2. Receive the gray scale pattern from the Pattern Generator.

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

4. Activate the adjustment mode display of Fig. 1-1 and press the channel button (12) on the remote control to select “R. BIAS”.

5. Press the CH. UP/DOWN button on the remote control toselect the “R. BIAS”, “G. BIAS”, “B. BIAS”, “B. DRIVE” or “G. DRIVE”.

6. Adjust the VOL. UP/DOWN button on the remote control to whiten the R. BIAS, G. BIAS, B. BIAS, B. DRIVE, and G. DRIVE at each step tone sections equally.

7. Perform the above adjustments 5 and 6 until the white color is looked like a white.

2-4: FOCUS

1. Receive the monoscope pattern.

2. Turn the Focus Volume fully counterclockwise once.

3. Adjust the Focus Volume until picture is distinct.

00 OSD 35

Fig. 1-1

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

4. Press the MENU button on the remote control to end the adjustments.

NO.

FUNCTION

OSD H

CUT OFF H. VCO

02 03

H. PHASE

AFC GAIN

V. SHIFT

H. SIZE V. SIZE

07 08

V. LINEARITY

VS CORRECTION

DRIVE R

DRIVE B R CUT OFF

12 13

G CUT OFF

B CUT OFF

BRIGHT MAX

BRIGHT CENT BRIGHT MIN

NO.

FUNCTION

CONTRAST MAX

CONTRAST CENT CONTRAST MIN

20 21

COLOR MAX

COLOR CENT

COLOR MIN

TINT SHARPNESS

25 26

Cb DELAY FINE

Cr DELAY FINE

Cb PEDESTAL ADJ

Cr PEDESTAL ADJ E/W PARABOLA

30 31

E/W CORNER

E/W TRAPEZIUM

LEVEL

SEPARATION1 SEPARATION2

Fig. 1-2

2-5: HORIZONTAL POSITION

1. Receive the monoscope pattern.

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

3. Activate the adjustment mode display of Fig. 1-1 and press the channel button (03) on the remote control to select "H.PHASE".

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

2-6: VERTICAL POSITION

1. Receive the monoscope pattern.

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

3. Adjust the VR401 until the horizontal line becomes fit to the notch of the shadow mask.

No. 52130

AV-14F704

2-7: VERTICAL SIZE

1. Receive the monoscope pattern.

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

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

4. 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%.

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

After the adjustment of Vertical Linearity, reconfirm the Vertical Position and Vertical Size adjustments.

1. Receive the monoscope pattern.

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

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

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

2-9: LEVEL

1. Receive the VHF HIGH (70dB).

2. Connect the AC voltmeter to the pin 6 of CP101.

3. Activate the adjustment mode display of Fig. 1-1 and press the channel button (33) on the remote control to select “LEVEL”.

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

2-10: OSD HORIZONTAL

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

2. Press the VOL. UP/DOWN button on the remote control until the difference of A and B becomes minimum.

(Refer to Fig. 2-1)

00 OSD 35

A B

Fig. 2-1

2-11: SEPARATION 1, 2 Please do the method (1) or method (2) adjustment.

Method (1)

1. Set the multi-sound signal generator for each different Lch and R-ch frequency (Ex. L-ch=2KHz, R-ch=400Hz) and receive the RF.

2. Connect the oscilloscope to the Audio Out Jack.

3. Activate the adjustment mode display of Fig. 1-1 and press the channel button (34) on the remote control to select “SEP1”.

4. Press the VOL. UP/DOWN button on the remote control to adjust it until the audio output wave becomes a fine sine wave.

5. Press the CH UP button once the set to “SEP 2” mode. Then perform the above adjustment 4.

Method (2)

1. Set the multi-sound signal generator L-ch=1KHz, R-ch =Non input and receive the RF.

2. Connect the oscilloscope to the Audio Out Jack (R-ch).

3. Press the AUDIO SELECT button on the remote control to set to the stereo mode.

4. Activate the adjustment mode display of Fig. 1-1 and press the channel button (34) on the remote control to select “SEP 1”.

5. Press the VOL. UP/DOWN button on the remote control to adjust it until the R-ch output becomes minimum.

6. Set the multi-sound signal generator L-ch=Non input, R-ch=1KHz and receive the RF.

7. Connect the oscilloscope to the Audio Out Jack (L-ch).

8. Activate the adjustment mode display of Fig. 1-1 and press the channel button (35) on the remote control to select “SEP 2”.

9. Press the VOL. UP/DOWN button on the remote control to adjust it until the L-ch output becomes minimum.

2-12: BRIGHT CENTER

1. Receive the monoscope pattern. (RF Input)

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

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

4. Press the VOL. UP/DOWN button on the remote control until the white 15% is starting to be visible.

5. Receive the monoscope pattern. (Audio Video Input)

6. Press the TV/VCR button on the remote control to set to the AV mode. Then perform the above adjustments 2~4.

7. Press the TV/VCR button on the remote control to set to the CS mode.

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

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

No. 52130

AV-14F704

2-13: TINT/COLOR CENT

1. Receive the color bar pattern. (RF Input)

2. Connect the oscilloscope to TP024.

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

4. Activate the adjustment mode display of Fig. 1-1 and press the channel button (24) on the remote control to select “TINT”.

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

6. Connect the oscilloscope to TP023.

7. Press the CH DOWN button 2 times to set to “COL. CENT” mode.

8. Adjust the VOLTS RANGE VARIABLE knob of the oscilloscope until the range between white 100% and 0% is set to 4.4 scales on the screen of the oscilloscope.

9. Press the VOL. UP/DOWN button on the remote control until the red color level is adjusted to 115 ± 10% of the white level.

(Refer to Fig. 2-3)

10. Receive the color bar pattern. (Audio Video Input)

11. Press the TV/VCR button on the remote control to set to the AV mode. Then perform the above adjustments 2~9.

12. Press the TV/VCR button on the remote control to set to the CS mode.

13. Activate the adjustment mode display of Fig. 1-1 and press the channel button (24) on the remote control to select “TINT”.

14 Press the VOL. UP/DOWN button on the remote control to set

the same step numbers as the AV.

15. Press the CH DOWN button 2 times to set to “COL.CENT” mode.

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

“A”

Fig. 2-2

2-14: CONTRAST MAX MANUAL

1. Activate the adjustment mode display of Fig. 1-1 and press the channel button (18) on the remote control to select “CONT. MAX”.

2. Press the VOL. UP/DOWN button on the remote control until the contrast step No. becomes “89”.

3. Receive a broadcast and check if the picture is normal.

4. Press the TV/VCR button on the remote control to set to the AV mode. Then perform the above adjustments 1~3.

5. Press the TV/VCR button on the remote control to set to the CS mode.

6. Activate the adjustment mode display of Fig. 1-1 and press the channel button (18) on the remote control to select “CONT. MAX”.

7. Press the VOL. UP/DOWN button on the remote control until the contrast step No. becomes “72”.

2-15: Confirmation of Fixed Value (step No.)

Please check if the fixed values of the each adjustment items are set correctly referring below.

NO. FUNCTION RF/AV/CS

02 H. VCO 03 04 AFC GAIN 06 05 V. SHIFT 00 06 H. SIZE 00 09 VS CORRECTION 42 15 BRIGHT MAX 150 17 BRIGHT MIN 75 19 CONTRAST CENT 50 20 CONTRAST MIN 18 21 COLOR MAX 90 23 COLOR MIN 00 25 SHARPNESS 35 26 Cb DELAY FINE 00 27 Cr DELAY FINE 00 28 Cb PEDESTAL ADJ 08 29 Cr PEDESTAL ADJ 08 30 E/W PARABOLA 31 31 E/W CORNER 31 32 E/W TRAPEZIUM 31

White 100%

100%

RED Level

Fig. 2-3

No. 52130

AV-14F704

3. PURITY AND CONVERGENCE ADJUSTMENTS

NOTE

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

performing the following adjustments.

2. Place the CRT surface facing east or west to reduce the

terrestrial magnetism.

3. Turn ON the unit and demagnetize with a Degauss Coil.

3-1: STATIC CONVERGENCE (ROUGH ADJUSTMENT)

1. 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.

2. Receive the green raster pattern from the color bar generator.

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

CRT.

4. Adjust center of screen to green, with red and blue on the sides,

using the pair of purity magnets.

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

the crosshatch pattern.

6. Combine red and blue of the 3 color crosshatch pattern on the

center of the screen by adjusting the pair of 4 pole magnets.

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

pole magnets.

8. 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.

1. Receive the green raster pattern from color bar generator.

2. 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.

3. Move the deflection yoke backward (to neck side) slowly, and

stop it at the position when the whole screen is green.

4. Confirm red and blue color.

5. 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.

1. Receive the crosshatch pattern from the color bar generator.

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

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

(Refer to Fig. 3-2-a)

2. 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

Fig. 3-2-a

WEDGE

WEDGE POSITION

Fig. 3-2-b

6 POLE MAGNETS 4 POLE MAGNETS PURITY MAGNETS

Fig. 3-1

No. 52130

AV-14F704

4. ELECTRICAL ADJUSTMENT PARTS LOCATION GUIDE (WIRING CONNECTION)

CRT PCB

CP806

TP003

W003

FB401

CP803

CRT

TP024

J801

CP802B

CD801

CP801A

TP023

R805

CP801B

CP401

R803

CD802

CP101

TU001

VR401

AC IN

CD501

CP502

L503

VR502

CRT

MAIN PCB

CP802A

J705

J706

SPEAKER

CP1001

J707

No. 52130

GUIDE FOR REPAIRING

IC DESCRIPTION

MAIN PCB OEC7093A (IC101)

No. Pin name Symbol I/O Logic Function Option

1 P11/SCL1 AUDIO MUTE O 0 Audio MUTE Output. C-MOS

2 P00/PWM0 EXT MUTE O 1 Audio MUTE Output for external Output. Nch-OD

3 P01/PWM1 VOLUME O 1 Volume PWM output. Nch-OD

4 P02/PWM2 BBE-H O BBE Control Output. Nch-OD

5 P03/PWM3/AD1 AFT I Voltage of tuning input. Nch-OD

6 P04/PWM4/AD2 KEY1 I Main unit key input. Nch-OD

7 P05/AD3 KEY2 I Main unit key input. Nch-OD

8 P06/INT2/AD4 X-RAY I Input terminal of X-RAY detection. Nch-OD

9 P07/INT1 REMOCON I Remote control input. Nch-OD

10 P20/SCLK/AD5 ON TIME LED O ON-TIMER LED control output. C-MOS

11 P21/AOUT/AD6 S IN I S-connectio input. C-MOS

12 P22/SIN/AD7 Y/C SW O External in select output. C-MOS

13 P23/TIM3 AUDIO SW O Audio in select output. C-MOS

14 P24/TIM2 O C-MOS

15 P25/INT3 OPOWER FAIL I 0 Power failure detector input. C-MOS

16 P26/X CIN DEGAUSS_H O 1 Degauss output. C-MOS

17 P27/X COUT X-RAY_TEST O 1 X-RAY detector input. C-MOS

18 CNVSS CNVSS GND

19 XIN X in I Main Oscillation.

20 XOUT X out O Main Oscillation.

21 VSS VSS GND

22 VCC VCC 5V

23 FILT FILT

24 HLF HLF O Filter of slicer.

25 VHOLD V.HOLD I Condenser of slicer.

26 CVIN CVIN I Video signal input.

27 RESET RESET I 0 Reset signal input.

28 FSCIN (FSC IN) I (Main Clock Occurrence circuit input)

29 PON CONT/P15 POWER O 1 Power control output. C-MOS

30 P31/SCL3 SCL1 O Serial clock output. (IIC BUS) C-MOS

31 P30/SDA3 SDA1 I/O Serial data input/output. C-MOS

32 CLK CONT/P10 (CLOCK CONT) O (Main Clock Request output) C-MOS

33 P55/OUT BRANK O 1 BLANK Output for OSD/CCD. C-MOS

34 P54/R RED R O 1 Red output of RGB image output. C-MOS

35 P53/G GREEN G O 1 Green output of RGB image output. C-MOS

36 P52/B BLUE B O 1 Blue output of RGB image output. C-MOS

37 P51/VSYNC V.SYNC I 0 Vertical synchronization input.

38 P50/HSYNC H.SENC I 0 Horizontal synchronization input.

39 P16/AD8/TIM2 SYNC I Input terminal for H-SYNC. C-MOS

40 P14/SDA2 IIC_OFF I 0 Serial clock/data stop input. C-MOS

41 P13/SDA1 PROTECT O 1 Output HIGH at turning off a television. C-MOS

42 P12/SCL2 H_CTL O 1 Output HIGH at turning off a television.

C-MOS

AV-14F704

No. 52130

AV-14F704

TROUBLESHOOTING GUIDE

NO POWER

Is the voltage at the point (A) in the Figure DC160V ?

Is the voltage at the point (B) in the Figure DC164V ?

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

Is the voltage at the point (E) in the Figure AC120V ?

Yes

Is the voltage at pin G of Q502 DC5V ?

Check Q514 and associated circuit.

Check R501 and R541.

Check the rectifying circuit.

Broken wire of L501.

Yes

Q502

Check Q502 and associated circuit.

T501

Q514

IC504

D501~D504

R501

Is the voltage on both ends of S501 AC120V ?

Broken wire of AC cord or check S501.

Yes

Broken wire of F501.

No. 52130

L501

F501

CD501

NO RASTER

AV-14F704

Does the RASTER appear at maximum BRIGHT/CONTRAST ?

Is the high voltage of ANODE 27KV~28KV ?

Is collector voltages of Q405 DC115V and Q402 DC27V ?

Yes

Is the voltage of pin 1 of CP801 DC180V ?

Check the 180V line.

Is the heater voltage at pin 4 of J801 AC6.4V ?

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 Q402 normal ?

Is the waveform at pin 8 of IC601 normal ?

Check IC601 and associated circuit.

Yes

Check Q402 and check peripheral circuit.

Check the circuit from pin 8 of IC601 to Q402.

No. 52130

AV-14F704

NO COLOR

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

Are the waveforms at pins 3, 4 and 5 of CP802 normal ?

Are the waveforms at pins 14, 15 and 16 of IC602 normal ?

Is the pulse of crystal X602 normal ?

Yes

Defect of CRT or contact defects of J801.

Check the output circuit and associated circuit.

Check R, G, B signal output from IC601 to CP802.

Check the associated circuit of IC601.

CHANG X602.

No. 52130

NO VERTICAL

AV-14F704

Is the waveform at pin 6 of CP401 normal ?

Is the waveform at pin 1 of IC401 normal ?

Is the waveform at pin 63 of IC601 normal ?

Check the associated circuit of IC601.

Yes

Is the voltage at pin 2 of IC401 25V?

Check the 25V line.

Yes

Check DY.

Check IC401 and check the peripheral circuit.

Check the circuit from pin 63 of IC601 to pin 1 of IC401.

No. 52130

AV-14F704

NO SOUND

Is sound setting appropriate ?

Yes

Is the waveform at pins 7 and 12 of IC1001?

Is the AUDIO signal at pins

16 and 19 of IC303?

Is the AUDIO signal input

at pins 3 and 30 of IC302?

Check IC902 and check

AUDIO signal in put.

Yes

Check speaker.

Check IC1001 and

check peripheral circuit.

Check IC302 and peripheral circuit.

NO CCD

Is the video signal at pin 26 of IC101 ?

Is the video signal at pin 17 of TU001 ?

Check IC601 and check

paripheral circuit.

Yes

Check IC101 and check peripheral circuit.

Check TU001 and check peripheral circuit.

No. 52130

+ 41 hidden pages