Sony KV-25FV10 Schematic

SERVICE MANUAL

MODEL COMMANDER DEST CHASSIS NO.

BA-4C CHASSIS

KV -20FV10 KV -20FV10 KV -21FV10 KV -21FV10C KV -25FV10A

RM-Y168 US SCC-S22B-A RM-Y168 CND SCC-S24B-A RM-Y168 E SCC-S23E-A RM-Y168 E SCC-S23F-A RM-Y168 E SCC-S23B-A

MICROFILM

RM-Y168KV-20FV10

TRINITRON® COLOR TV

KV-20FV10/21FV10/21FV10C/25FV10A

SPECIFICATIONS

KV-20FV10 KV-21FV10/21FV10C KV-25FV10A

Power Requirements 120V, 60 Hz 120-220V, 50-60Hz 120-220V, 50-60Hz

Number of inputs/outputs

Video Input S Video Input Audio Input Audio Output

(1)

(2)

(3)

(4)

Speaker Output (W) 5W x 2 5W x 2 10W x 2

Power Consumption (W)

In Use (Max) 125W 125W 150W InStandby 1W1W1W

Dimensions (W/H/D)

(mm) 562 x 466 X 503 mm 562 x 466 X 503 mm 652 x 524.3 x 467.3 mm (in) 22

Mass

222 111 222 111

/8x183/8x183/4in 221/8x183/8x183/4in 253/4x2011/16x187/16in

(kg) 27 kg 27 kg 40 kg (lbs) 59 lbs 59 lbs 88 lbs 3 oz

Tele vision system

American TV standard/NTSC P AL M, N (KV-25FV10A ONL Y)

1 Vp-p 75 ohms unbalanced, sync negative

Y: 1 Vp-p 75 ohms unbalanced, sync negative C: 0 286 Vp-p (Burst signal), 75 ohms

500 mVrms (100% modulation), impedance: 47 kilohms

More than 408 mVrms at the maximum volume setting (variable) Morethan408 mVrms(fix)

Channel coverage

VHF:2-13/UHF:14-69/CA TV :1-125

Visible screen size

20” picture measured diagonally 24" picture measured diagonally (KV -25FV10A ONLY)

Actual screen size

21" picture measured diagonally 25" picture measured diagonally (KV -25FV10A ONLY)

Antenna

75 ohm external terminal for VHF/UHF

Supplied accessories

Remote Commander RM-Y168 (all models) Size AA (R6) batteries (2)

( • ) SRS (SOUND RETRIEV AL SYSTEM)

Optional accessories

Dipole antenna Connecting cables VMC-810S/820S, VMC-720M, YC-15V/30V , RK74A U/V mixer EAC-66

Design and specifications are subject to change without notice.

The ( • ) SRS (SOUND RETRIEVAL SYSTEM) is manufactured by Sony Corporation under license from SRS Labs, Inc. It is covered by U.S. Patent No. 4,748,669. Other U.S. and foreign patents pending.

The word ‘SRS’ and the SRS symbol ( • ) are registered trademarks of SRS Labs, Inc.

BBE and BBE symbol are trademarks of BBE Sound, Inc. and are licensed by BBE Sound, Inc. under U.S. Patent No. 4,638,258 and 4,482,866.

— 2 —

KV-20FV10/21FV10/21FV10C/25FV10A

TABLE OF CONTENTS

Section Title Page

Warnings and Cautions............................................................................................................................................................... 4

Self-Diagnostic Function ............................................................................................................................................................. 4

Safety Check-Out Instructions .................................................................................................................................................... 7

1. GENERAL........................................................................................................................................................... 8

2. DISASSEMBLY

2-1. Rear Cover Removal ....................................................................................................................................................14

2-2. A Board Removal ..........................................................................................................................................................14

2-3. Service Position ............................................................................................................................................................ 1 4

2-4. Picture Tube Removal ...................................................................................................................................................15

3. SET-UP ADJUSTMENTS

3-1. Beam Landing............................................................................................................................................................... 16

3-2. Convergence .................................................................................................................................................................17

3-3. Focus ............................................................................................................................................................................. 1 8

3-4. Screen (G2) ................................................................................................................................................................... 18

3-5. Method of Setting the Service Adjustment Mode .........................................................................................................19

3-6. White Balance Adjustments.......................................................................................................................................... 19

4. SAFETY RELATED ADJUSTMENTS

4-1. R582 and R584 Confirmation Method (HV Hold-Down Confirmation and Readjustments) ...................................20

4-2. B+ Voltage Confirmation and Adjustment ..................................................................................................................... 20

5. CIRCUIT ADJUSTMENTS

5-1. Setting the Service Adjustment Mode ..........................................................................................................................22

5-2. Memory Write Confirmation Method .............................................................................................................................22

5-3. Adjustment Buttons and Indicators............................................................................................................................... 22

5-4. A Board Adjustments .................................................................................................................................................... 24

6. DIAGRAMS

6-1. Block Diagram...............................................................................................................................................................2 7

6-2. Circuit Board Location ..................................................................................................................................................30

6-3. Printed Wiring Boards and Schematic Diagrams .........................................................................................................30

• A Board ....................................................................................................................................................................31

• C Board ....................................................................................................................... ............................................. 38

• G Board ....................................................................................................................................................................39

• HZ Board ..................................................................................................................................................................4 2

• V Board ....................................................................................................................................................................43

6-4. Semiconductors ............................................................................................................................................................4 9

7. EXPLODED VIEW

7-1. Chassis (KV-20FV10/21FV10/21FV10C) ..................................................................................................................... 50

7-2. Chassis (KV-25FV10A ONLY) .......................................................................................................................................51

8. ELECTRICAL P AR TS LIST.................................................................................................................................................52

— 3 —

KV-20FV10/21FV10/21FV10C/25FV10A

WARNINGS AND CAUTIONS

CAUTION

SHORT CIRCUIT THE ANODE OF THE PICTURE TUBE AND THE ANODE CAP TO THE METAL CHASSIS, CRT SHIELD, OR CARBON PAINTED ON THE CRT, AFTER REMOVING THE ANODE.

WARNING!!

AN ISOLATION TRANSFORMER SHOULD BE USED DURING ANY SERVICE TO AVOID POSSIBLE SHOCK HAZARD, BECAUSE OF LIVE CHASSIS. THE CHASSIS OF THIS RECEIVER IS DIRECTLY CONNECTED TO THE AC POWER LINE.

SAFETY-RELATED COMPONENT WARNING!!

COMPONENTS IDENTIFIED BY SHADING AND MARK

ON THE SCHEMA TIC DIAGRAMS, EXPLODED VIEWS, AND IN THE PARTS LIST ARE CRITICAL FOR SAFE OPERATION. REPLACE THESE COMPONENTS WITH SONY PARTS WHOSE PA RT NUMBERS APPEAR AS SHOWN IN THIS MANUAL OR IN SUPPLEMENTS PUBLISHED BY SONY. CIRCUIT ADJUSTMENTS THAT ARE CRITICAL FOR SAFE OPERA TION ARE IDENTIFIED IN THIS MANUAL. FOLLOW THESE PROCEDURES WHENEVER CRITICAL COMPONENTS ARE REPLACED OR IMPROPER OPERA TION IS SUSPECTED .

A TTENTION!!

APRES AVOIR DECONNECTE LE CAP DE L'ANODE, COURT-CIRCUITER L'ANODE DU TUBE CATHODIQUE ET CELUI DE L'ANODE DU CAP AU CHASSIS METALLIQUE DE L'APPAREIL, OU AU COUCHE DE CARBONE PEINTE SUR LE TUBE CATHODIQUE OU AU BLINDAGE DU TUBE CATHODIQUE.

ATTENTION!!

AFIN D'EVITER TOUT RESQUE D'ELECTROCUTION PROVENANT D'UN CHÁSSIS SOUS TENSION, UN TRANSFORMATEUR D'ISOLEMENT DOIT ETRE UTILISÉ LORS DE TOUT DÉPANNAGE. LE CHÁSSIS DE CE RÉCEPTEUR EST DIRECTEMENT RACCORDÉ À L'ALIMENTATION SECTEUR.

A TTENTION AUX COMPOSANTS RELATIFS A LA SECURITE!!

LES COMPOSANTS IDENTIFIES PAR UNE TRAME ET PAR UNE MARQUE

SUR LES SCHEMAS DE PRINCIPE, LES VUES EXPLOSEES ET LES

LISTES DE PIECES SONT D'UNEIMPORTANCE CRITIQUE POUR LA SECURITE DU FONCTIONNEMENT. NE LES REMPLACER QUE PAR DES COMPOSANTS SONY DONT LE NUMERO DE PIECE EST INDIQUE DANS LE PRESENT MANUEL OU DANS DES SUPPLEMENTS PUBLIES P AR SONY. LES REGLAGES DE CIRCUIT DONT L'IMPORTANCE EST CRITIQUE POUR LA SECURITE DU FONCTIONNEMENT SONT IDENTIFIES DANS LE PRESENT MANUEL. SUIVRE CES PROCEDURES LORS DE CHAQUE REMPLACEMENT DE COMPOSANTS CRITIQUES, OU LORSQU'UN MAUV AIS FONTIONNEMENT SUSPECTE.

SELF-DIAGNOSTIC FUNCTION

The units in this manual contain a self-diagnostic function. If an error occurs, the ST ANDBY/TIMER LED will automatically begin to flash. The number of times the LED flashes translates to a probable source of the problem. A definition of the STANDBY/TIMER LED flash indicators is listed in the instruction manual for the user’s knowledge and reference. If an error symptom cannot be reproduced, the Remote Commander can be used to review the failure occurrence data stored in memory to reveal past problems and how often these problems occur.

Diagnostic Test Indicators

When an error occurs, the STANDBY/TIMER LED will flash a set number of times to indicate the possible cause of the problem. If there is more than one error, the LED will identify the first of the problem areas.

Results for all of the following diagnostic items are displayed on screen. No error has occurred if the screen displays a “0”.

Diagnostic Item

Description

Powerdoes not turn on Does notlight

+B over curren t (OCP)* 2times 2:0 or 2:1 • H.OUT(Q502)is shorted. (A Board)

Verticaldeflectionstopped* 4 times 4:0 or 4:1 • +13V is not supplied.(A Board)

White balance failur e (not balanced)

No. of Times

ST AN DB Y/T IM ER

LED Flashes

5 times 5:0 or 5:1 • Video OUT(IC541) is faulty .(A Board)

Self-diagnosticDisplay/

Diagnostic Result

Proba bl e Cause

Location

• Power cord is not plugged in.

• Fuse is burned out. (F600) (G Board)

• IC1751 is shorted. (C Board)

• IC541 is faulty.(A Board)

• IC301 is faulty.(A Board)

• Screen (G2) is improperlyadjusted.**

Detected Symptoms

• Power does not come on.

• No poweris suppliedto the TV.

• AC powersupply is faulty .

• Power does not come on.

• Load on power lineis shorted.

• Has entered standby state afterhorizontal raster.

• Verticaldeflection pulse is stopped.

• Power line is shorted or powersupply is stopped.

• No raster is generated.

• CRT cathodecurrent detection refe rence pulse output is small.

* If a +B overcurrentis detected, stoppageof the vertical deflection is detectedsimultaneously .

The symptomthat is diagnose d first by the microc ontrol leris displayed on the screen.

** Refer to Screen (G2) Adjus tmentsin Section 3-4 of this manual.

— 4 —

Display of Standby/Timer LED Flash Count

2 times 4 times 5 times

KV-20FV10/21FV10/21FV10C/25FV10A

LED ON 0.3 sec. LED OFF 0.3 sec.

Diagnostic Item Flash Count*

+B overcurrent 2 times V ertical deflection stopped 4 times White balance failure 5 times

*One flash count is not used for self-diagnostic.

LED OFF

3 sec.

STANDBY/TIMER LED

Stopping the Standby/Timer LED Flash

Turn off the power switch on the TV main unit or unplug the power cord from the outlet to stop the STANDBY/TIMER LAMP from flashing.

Self-Diagnostic Screen Display

For errors with symptoms such as “power sometimes shuts off” or “screen sometimes goes out” that cannot be confirmed, it is possible to bring up past occurrences of failure on the screen for confirmation.

To Bring Up Screen Test

In standby mode, press buttons on the Remote Commander sequentially, in rapid succession, as shown below:

Display Channel

Sound volume

Power ON

Self-Diagnostic Screen Display

SELF DIAGNOSTIC

2: 0 3: N/A 0 4: 0 5: 1 101: N/A 0

Note that this differs from entering the service mode (sound volume

Numeral “0” means that no fault was detected.

Numeral “1” means a fault was detected one time only.

— 5 —

KV-20FV10/21FV10/21FV10C/25FV10A

Handling of Self-Diagnostic Screen Display

Since the diagnostic results displayed on the screen are not automatically cleared, always check the self-diagnostic screen during repairs. When you have completed the repairs, clear the result display to “0”.

Unless the result display is cleared to “0”, the self-diagnostic function will not be able to detect subsequent faults after completion of the repairs.

Clearing the Result Display

To clear the result display to “0”, press buttons on the Remote Commander sequentially when the diagnostic screen is displayed, as shown below:

ENTERChannel

Quitting the Self-Diagnostic Screen

To quit the entire self-diagnostic screen, turn of f the power switch on the Remote Commander or the main unit.

Self-Diagnostic Circuit

FROM

CRT

FROM

IC521 PIN 7

IC301

Y/CHROMA JUNGLE

K IN

HP/PROTECT

SDA

IC541

V. OUT

REF

IC001

SYSTEM

IO-BDAT

O-LED

DISPLAY

I-PROT

IO-SDAT

IC003

MEMORY

B-DAT

+B overcurrent (OCP) Occurs when an overcurrent on the +B (115V) line is detected by pin 18 of IC301. If the voltage

of pin 18 of IC 301 is less than 1V when V.SYNC is more than seven verticals in a period, the unit will automatically turn off.

Vertical deflection stopped Occurs when an absence of the vertical deflection pulse is detected by pin 17 of IC001. Power

supply will shut down when waveform interval exceeds 2 seconds.

White balance failure If the RGB levels* do not balance within 2 seconds after the power is turned on, this error will be

detected by IC301. TV will stay on, but there will be no picture.

*(Refers to the RGB levels of the AKB detection Ref pulse that detects 1K.)

— 6 —

SAFETY CHECK-OUT

KV-20FV10/21FV10/21FV10C/25FV10A

After correcting the original service problem, perform the following saf ety checks before releasing the set to the customer:

1. Check the area of your repair for unsoldered or poorly soldered connections. Check the entire board surface for solder splashes and bridges.

2. Check the interboard wiring to ensure that no wires are “pinched” or touching high-w attage resistors.

3. Check that all control knobs, shields, covers, ground straps, and mounting hardware have been replaced. Be absolutely certain that you have replaced all the insulators.

4. Look for unauthorized replacement parts, particularly transistors, that were installed during a previous repair . Point them out to the customer and recommend their replacement.

5. Look for parts which, though functioning, show obvious signs of deterioration. Point them out to the customer and recommend their replacement.

6. Check the line cords for cracks and abrasion. Recommend the replacement of any such line cord to the customer.

7. Check the B+ and HV to see if they are specified values. Make sure your instruments are accurate; be suspicious of your HV meter if sets always have low HV.

8. Check the antenna terminals, metal trim, “metallized” knobs, screws, and all other exposed metal parts for AC leakage. Check leakage as descr ibed below.

Leakage Test

The AC leakage from any exposed metal part to earth ground and from all exposed metal parts to any exposed metal part having a return to chassis, must not exceed

0.5 mA (500 microamperes). Leakage current can be measured by any one of three methods.

1. A commercial leakage tester, such as the Simpson 229 or RCA WT-540A. Follow the manufacturers' instructions to use these instructions.

2. A battery-operated AC milliammeter. The Data Precision 245 digital multimeter is suitable for this job.

3. Measuring the voltage drop across a resistor by means of a VOM or battery-operated A C v oltmeter . The “limit” indication is 0.75 V, so analog meters must have an accurate low voltage scale. The Simpson’s 250 and Sanwa SH-63Trd are examples of passive VOMs that are suitable . Nearly all battery-operated digital multimeters that have a 2 VAC range are suitable (see Figure A).

How to Find a Good Earth Ground

A cold-water pipe is a guaranteed earth ground; the coverplate retaining screw on most AC outlet boxes is also at earth ground. If the retaining screw is to be used as y our earth ground, verify that it is at ground by measuring the resistance between it and a cold-water pipe with an ohmmeter. The reading should be zero ohms. If a cold-water pipe is not accessible, connect a 60- to 100-watt troub lelight (not a neon lamp) between the hot side of the receptacle and the retaining screw . Try both slots, if necessary , to locate the hot side on the line; the lamp should light at normal brilliance if the screw is at ground potential (see Figure B).

0.15 F

To Exposed Metal Parts on Set

1.5 k

Earth Ground

AC Voltmeter (0.75 V)

— 7 —

Trouble Light

AC Outlet Box

Figure B. Checking for earth ground.Figure A. Using an AC voltmeter to check AC leakage.

Ohmmeter

Cold-water Pipe

Connecting Additional Equipment

TV and VCR

Connect the coaxial cable from your TV antenna or cable TV to the IN jack on your VCR.

Connect a coaxial cable (not supplied) from the OUT jack on your VCR to the VHF/UHF IN jack on the TV.

(Optional connection)

If your VCR is equipped with video inputs, for better picture quality you should connect A/V cables from AUDIO and VIDEO OUT on your VCR to AUDIO/VIDEO IN on your TV. You can use the button to switch between the TV and VCR inputs.

✍

To watch video programs from your VCR, tune your TV to channel 3 or 4 (as set on the rear of your VCR).

✍

For optimum picture quality, use S VIDEO instead of the yellow A/V cable. S VIDEO does not provide sound, the audio cables must still be connected.

(Optional connection)

VCR

From

Cable/antenna

SECTION 1 GENERAL

KV-20FV10/21FV10/21FV10C/25FV10A

The instructions mentioned here are partial abstracts from the Operating Instruction Manual.

The page numbers shown reflect those of the Operating Instruction Manual.

Connecting Your TV

Read this chapter before setting up your TV for the first time. This section covers basic connections in addition to any optional equipment you may be connecting.

— 8 —

Basic Connections

TV with indoor or outdoor antenna, or CATV cable

Depending on the cable available in your home, choose one of the connections below:

✍

If you are connecting to an indoor or outdoor antenna, it will be necessary to adjust the orientation of the antenna for best reception.

TV and Cable Box

TV, VCR, and Cable box

Connect the coaxial cable from the wall to the IN jack on your cable box.

Connect a coaxial cable (not supplied) from the OUT jack on your cable box to the IN jack on your VCR.

Connect a coaxial cable (not supplied) from the OUT jack on your VCR to the VHF/UHF IN jack on the TV.

(Optional connection)

✍

If you will be controlling all channel selection through your cable box, you should consider using the CHANNEL FIX feature on page 20.

✍

For optimum picture quality, use S VIDEO instead of the yellow A/V cable. S VIDEO does not provide sound, the audio cables must still be connected.

Cable

(Optional connection)

Cable box

VCR

Connect the coaxial cable from the wall to the IN jack on your cable box.

Connect a coaxial cable (not supplied) from the OUT jack on your

— 9 —

cable box to the VHF/UHF IN jack on the TV.

✍

To view channels from your cable box, tune your TV to channel 3 or 4 (as set on the rear panel of your cable box).

✍

If you will be controlling all channel selection through your cable box, you should consider using the CHANNEL FIX feature on page 20.

KV-20FV10/21FV10/21FV10C/25FV10A

TV and Digital Satellite Receiver

TV, Digital Satellite Receiver and VCR

Connect the cable from your satellite antenna to SATELLITE IN on the satellite receiver.

Attach the coaxial connector from your cable or antenna to VHF/UHF IN on your VCR.

Using a coaxial cable, connect VHF/UHF OUT on your VCR to VHF/UHF on your TV.

Using A/V connectors, connect AUDIO and VIDEO OUT on your satellite receiver to AUDIO and VIDEO IN on your VCR.

Using A/V connectors, connect AUDIO and VIDEO OUT on your VCR to AUDIO and VIDEO IN on your TV.

✍

To view from the satellite or VCR, select the video input to which your satellite receiver or VCR is connected by pressing on the remote control.

Satellite receiver

Cable

VCR

Satellite antenna

From

cable/ antenna

KV-20FV10/21FV10/21FV10C/25FV10A

Satellite antenna cable

— 10 —

Connect the cable from your satellite antenna to SATELLITE IN on the satellite receiver.

Attach the coaxial connector from your cable or antenna to VHF/UHF on your TV.

Using A/V connectors, connect AUDIO and VIDEO OUT on your satellite receiver to AUDIO and VIDEO IN on your TV.

✍

You can use the

✍

For optimum picture quality, use S VIDEO instead of the yellow A/V cable. S VIDEO does not provide sound, your audio connectors must still be connected.

Satellite receiver

button to switch between the satellite receiver and TV.

Connecting a Camcorder

Connecting an audio system

Using audio connectors, connect AUDIO OUT on your TV to one of the unused line inputs (e.g. TV, AUX, TAPE 2) on your stereo.

✍

Set your stereo to the chosen line input. See page 16 for additional audio setup instructions.

AUDIO-L

AUDIO-R

Line input

Using A/V cables, connect AUDIO and VIDEO OUT on your camcorder to AUDIO and VIDEO IN on your TV.

(Front A/V Panel)

— 11 —

Connecting a DVD Player

Using A/V connectors, connect LINE OUT on your DVD to VIDEO IN on your TV.

✍

For optimum picture quality, use S VIDEO instead of the yellow A/V cable. S VIDEO does not provide sound, your audio connectors must still be connected.

A/V output

(Rear of DVD player)

A/V outputs

(Rear of TV)

KV-20FV10/21FV10/21FV10C/25FV10A

Using the Remote Control and

Cycles through available AUTO VOLUME settings (see page 16).

JUMP Alternates back and forth

between the last two channels selected with the buttons.

GUIDE Brings up the custom guide of

your satellite receiver.

MENU Displays the on-screen menu.

Press again to exit the menu at any time.

RESET Press to return to factory settings

while in the on-screen menu.

CODE SET Use to program your remote

control to operate connected video equipment, (see page 29).

Basic Functions

This section shows you how to use more advanced buttons on the remote control and how to use the on-screen menus.

KV-20FV10/21FV10/21FV10C/25FV10A

— 12 —

Button Description POWER Press when you want to turn

FUNCTION Press when you want to control

MUTING Instantly turns off the sound.

SYSTEM OFF Powers off all Sony equipment at

TV/VIDEO Cycles through available video

PICTURE MODE Cycles through the available

SLEEP Turns the TV off automatically in

MTS/SAP Cycles through the Multi-

DISPLAY Press once to show current time,

connected equipment on and off.

connected equipment with your remote control.

Press again or press to restore sound.

once.

inputs.

Moves the cursor in the onscreen menus. Press the arrow buttons to move the cursor, press the center button to select or access an option.

VIDEO MODE settings.

approximately 30, 60 or 90 minutes. Cancel by pressing until SLEEP OFF appears.

channel TV Sound (MTS) options: STEREO, SAP (Second Audio Programming), MONO.

(if set) and channel number. Press again to activate CAPTION VISION settings, if available. To cancel, press again until DISPLAY OFF appears.

Troubleshooting

If, after reading these operating instructions, you have additional questions related to the use of your Sony television, please call our Direct Response Center at 1-800-222-SONY (7669) (U.S. residents only). (416) 499-SONY (7669) (Canadian residents only).

Cable stations don’t seem to work

❏ Make sure CABLE is set to ON in the SET UP menu

(page 20).

❏ Use AUTO PROGRAM to add channels that are not

presently in the memory (page 20).

Remote Control does not operate

❏ Batteries could be weak. Replace them (page 2). ❏ Move the TV 3-4 feet away from fluorescent lights.

The TV needs to be cleaned

❏ Clean the TV with a soft dry cloth. Never use strong

solvents such as thinner or benzine, which might damage the finish of the cabinet.

Lost password for PARENTAL CONTROL

❏ In the password screen, enter the following master

password: 4357. After using the master password, you must create a new password.

If you are having a problem with your TV, try the suggestions below. If the problem persists, contact your nearest Sony dealer.

No picture, no sound

— 13 —

Poor or no picture, good sound

Good picture, no sound

No color ❏ Adjust COLOR in the VIDEO menu (page 15). Only snow

appears on the screen

Dotted lines or stripes

Double images or ghosts

Cannot receive higher number channels (UHF) when using an antenna

❏ Make sure the power cord is plugged in. ❏ If a red light is flashing on the front of your TV for

more than a few minutes, call your local service center.

❏ Check your PARENTAL CONTROL settings, (pages

25-26).

❏ Check the TV/VIDEO settings: when watching TV, set

to TV; when watching video equipment, set to VIDEO (page 15).

❏ Make sure the batteries have been inserted correctly

into the remote control.

❏ Try another channel, it could be station trouble. ❏ Adjust PICTURE in the VIDEO menu (page 15). ❏ Adjust BRIGHTNESS in the VIDEO menu (page 15). ❏ Check the antenna and/or cable connections (page 3). ❏ Press so that MUTING disappears from the

screen (page 11).

❏ Check your AUDIO settings. Your TV may be set to

SAP (page 16).

❏ Check the CABLE setting in the SET UP menu

(page 20).

❏ Check the antenna and/or cable connections (page 3). ❏ Make sure the channel selected is currently

broadcasting.

❏ Adjust the antenna. ❏ Move the TV away from other electronic equipment.

Some electronic equipment can create electrical noise, which can interfere with TV reception.

❏ Check your outdoor antenna or call your cable service.

❏ Make sure CABLE is set to OFF in the SET UP menu

(page 20).

❏ Use AUTO PROGRAM to add channels that are not

presently in the memory (page 20).

KV-20FV10/21FV10/21FV10C/25FV10A

2-1. REAR COVER REMOVAL

SECTION 2

DISASSEMBLY

KV -25FV10A

Rear Cover

Six Screws

(+BVTP 4x16)

Two Screws

(+BVTP 3x10)

KV-20FV10/21FV10/21FV10C

Rear Cover

Four Screws

(+BVTP 4x16)

Two Screws

(+BVTP 3x10)

2-2. A BOARD REMOVAL 2-3. SERVICE POSITION

C Board

G Board

A Board

G Board

V Board

HZ Board

(KV-25FV10A ONLY)

A Board

C Board

V Board

HZ Board

(KV-25FV10A ONLY)

— 14 —

2-4. PICTURE TUBE REMOVAL

G Board

A Board

Cushion

Degaussing Coil

Neck Assy.

Deflection Yoke

Anode Cap

C Board

Picture Tube

Tension Spring (B)

Tuner

V Board

Speaker

Tapping Screw

WARNING:

BEFORE REMOVING

THE ANODE CAP

High voltage remains in the CRT even after the power is disconnected. T o avoid electric shock, discharge CR T before attempting to remove the anode cap. Short between anode and CRT coated earth ground strap.

Coated

Earth

Ground

Strap

KV-20FV10/21FV10/21FV10C/25FV10A

ANODE CAP REMOVAL

WARNING: High voltage remains in the CRT even after the power is disconnected. To avoid electrical shock, discharge the CRT before

NOTE: After removing the anode, short circuit the anode of the picture tube and the anode cap to either the metal chassis, CRT shield,

attempting to remove the anode cap. Short between anode and coated earth ground strap of CRT.

or carbon painted on the CRT.

REMOVAL PROCEDURES

Anode Button

Turn up one side of the rubber cap in the direction indicated by arrow

Use your thumb to pull the rubber

cap firmly in the direction indicated by arrow

When one side of the rubber cap separates from the anode button, the anode cap can be removed by turning the rubber cap and pulling it in the direction of arrow

HOW TO HANDLE AN ANODE CAP

Do not use sharp objects which may cause damage to the surface of the anode cap.

To avoid damaging the anode cap, do not squeeze the rubber covering too hard. A material fitting called a shatter-hook terminal is built into the rubber.

Do not force turn the foot of the rubber cover. This may cause the shatter-hook terminal to protrude and damage the rubber.

— 15 —

KV-20FV10/21FV10/21FV10C/25FV10A

SET-UP ADJUSTMENTS

SECTION 3

The following adjustments should be made when a complete realignment is required or when a new picture tube is installed.

These adjustments should be performed with rated power supply voltage unless otherwise noted.

Set the controls as follows unless otherwise noted: VIDEO MODE: ST ANDARD

PICTURE control ................. Normal

BRIGHTNESS control ......... Normal

3-1. BEAM LANDING

Before beginning adjustment procedure:

1. Degauss the entire screen.

2. Feed in the white pattern signal.

Adjustment Procedure

1. Input a raster signal with the pattern generator.

2. Loosen the deflection yoke mounting screw and set the purity control to the center as shown below.

Perform the adjustments in order as follows:

1. Beam Landing

2. Convergence

3. Focus

4. Screen (G2)

5. White Balance

Note: T est equipment required:

• Color bar pattern generator

• Degausser

• DC power supply

• Digital multimeter

5. Move the deflection yoke forward and adjust so that the entire screen becomes green.

Purity Control

3. Turn the raster signal of the pattern generator to green.

4. Move the deflection yoke backward and adjust the purity control so that green is in the center and red and blue are at the sides evenly.

Blue Red

Green

6. Switch over the raster signal to red and blue and confirm the condition.

7. When the position of the deflection yoke is determined, tighten it with the deflection yoke mounting screw.

8. If landing at the corner is not right, adjust by using the disk magnets.

Purity control

corrects this area

Disk magnets

or rotatable disk

Deflection yoke positioning

corrects these areas

magnets correct

these areas (a-d)

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