Casio tv3 Schematic

Basic Information for

INDEX

Casio Pocket Television

Vol.3 CIRCUIT OPERATION

Contents

PAGE

TELEVISION TRANSMISSION SYSTEM ...........................................................

Color System ....................................................................................................

TV System ........................................................................................................

Channel System ................................................................................................

Details of Color System ....................................................................................

Details of TV System ........................................................................................

Details of TV Channel ......................................................................................

World TV Broadcast System ............................................................................

Casio TV Model ................................................................................................

BLOCK DIAGRAM ..............................................................................................

VHF, UHF .........................................................................................................

Rod Antenna ....................................................................................................

PCB Ass'y ........................................................................................................

Display Ass'y ....................................................................................................

AD PCB ............................................................................................................

Back Light ........................................................................................................

Power Supply ...................................................................................................

CIRCUIT OPERATION .......................................................................................

Tuner ................................................................................................................

IC200 ...............................................................................................................

IC300 ................................................................................................................

IC400 ................................................................................................................

IC700 ................................................................................................................

Tuning Operation ..............................................................................................

Adjustment .......................................................................................................

Troubleshooting ...............................................................................................

Trouble example ..............................................................................................

SCHEMATIC DIAGRAM & WAVEFORMS .........................................................

Waveforms ......................................................................................................

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TELEVISION TRANSMISSION SYSTEM

Three Systems

TV transmissionsystemsarenotthesamethroughoutth eworld:Colorsystem, TV system andChannelaredifferent.T he
countriesforwhich aparticular model issuitableareindicatedi n t he salesliteratureandinstructionbookletsupplied, andare
printedonthe box inwhicheach televisionispacked.

Color system

Therearethree colortransmissionsystemsintheworld:NTSC,PALandSECAM.

Ifthe color systemsaredifferent,TV doesnotg etin color.

e.g.

ColorSystem TVSystem ChannelSystem
Brazil PAL M/M US
U.S.A. NTSC M/M US

ColorSystem TVSystem ChannelSystem
SaudiArabia SECAM B/G,H CCIR
German y PAL B/G,H CCIR

T V System

Therearefourteen TVsystemsin the world: From A to N. Eachsystemisdiffer ent fromscanningline, sound

frequencyandmodulation system.
Ifthe TV systems aredifferent, TVdoesnot getapicture andasound.
TVsystemsareindicatedi n the rating plateon the lower case.

e.g.

ColorSystem TVSystem ChannelSystem
Brazil PAL M/M US
Argentina PA L N/N US

Channel System

Ifthe channel(TVfrequency)isdifferent,TVcannotget th e local channel.

e.g.

Japan U.S.A.
ColorSystem NTSC NTSC
TVSystem M/M M/M
Channel Japan US

1ch 91.25MHz ­2ch 97.25MHz 55.25MHz
3ch 103.25MHz 61.25MHz
4ch 171.25MHz 67.25MHz

It is no t possible t o convert it t o work i n a ny country otherthanthe o ne for which it is designed.

-1-

Details of Color System

System NTSC PAL SECAM NTSC: A 525-line 60-field color television system

(Germany) (France) originally developed in the USA.

Scanning lines 525 625 625 The 3.58MHz sub carrier is used to

transmit color information.

Field frequency (MHz) 59.94 50 50

PAL: A 625-line 50-field color television system

Interlacing ration 2 : 1 2 : 1 2 : 1 originally developed in West Germany.

PAL is improved about the phase distortion

Aspect ration 4 : 3 4 : 3 4 : 3 of NTSC. PAL is basically the same as

NTSC. But PAL is different from NTSC in

Line frequency (MHz) 15.734 15.625 15.625 the way of the color signal transmission.

The phase of B-Y signal is fixed 90 degree.

Channel bandwidth(MHz) 6 8 8 The phase of R-Y signal changes at 0 and

180 degree on every horizontal scanning

Luminance signal(MHz) 4.2 5 6 line. The influence of the phase distortion is

denied by this way.

Color signal (MHz) I 1.5 R-Y 1.3 R-Y 1.3 The 4.43MHz sub carrier is used to transmit

Q 0.5 B-Y 1.3 B-Y 1.3 color information.

Sound carrier-frequency +4.5 +5.5 +6.5 SECAM: A 625-line 50-field color television

(MHz) system originally developed in France.

Video Modulation AM negative AM negative AM positive Sub carrier frequency is different from

every lines, R-Y signal:4.40MHz, B-Y

Sound modulation FM FM AM signal 4.25MHz, the phase of sub

carrier changes over beginning of
scanning lines. The merit of SECAM is
strong about phase jitters, and have not
cross talk both of two color signals.

Details of TV System

System CCIR Belgium OIRT(1) France Luxembourg CCIR

(VHF) (VHF)

Broadcast System B C D E F G,H
Scanning line 625 625 625 819 819 625
Channel bandwidth 7 MHz 7 MHz 8 MHz 14 MHz 7 MHz 8 MHz
fs(audio) - fv(video) +5.5MHz +5.5MHz +6.5MHz +11.5MHz +5.5MHz +5.5MHz
Audio modulation F3(+/-50kHz) A3 F3(+/-50kHz) A3 A3 F3(+/-50kHz)

System UK(UHF), OIRT(2) France USA USA 625

Ireland (UHF) (Argentina)

Broadcast System I K,K1 L M N
Scanning line 625 625 625 525 625
Channel bandwidth 8 MHz 8 MHz 8 MHz 6 MHz 6 MHz
fs(audio) - fv(video) +6.0MHz +6.5MHz +6.5MHz +4.5MHz +4.5MHz
Audio modulation F3(+/-50kHz) F3(+/-50kHz) A3 F3(+/-25kHz) F3(+/-25kHz)

A3: AM CCIR: International OIRT Organization
F3: FM Radio International de

Consultative Radio diffusion
Committee Television

- 2 -

Details o f TV Channel

1) TV Channel

In the United States, the low band of television stations occupies the frequency range 54 - 88MHz, with a small gap of
4MHzbetweenchannel 4 and 5. (This band -72 to 76MHz-is usedby otherservices.)Betweenthelow-bandandthe high
band stations there isafrequencyspace (88 - 174MHz)that isoccupied by FM broadcastinga nd government and aircraft
communicationsservices.
Channel 14, thefirst of UHF channels, occupies the band 47 0 - 476MHz, channel 15, 476 - 482MHz, channel 16, 48 2 ­488MHz,and so on,all the wayup to890MHz.Within this band,470 - 890MHz(atotalof 420MHz),70 televisionchannels
areaccommodated. Likethe UHFallocations,eachUHFtelevision channelis6MHzwide.

JapanVHFChannel

CH.NO. VideoFrequency Sound Frequency

IF 58.75MHz 54.25MHz

1 91.25MHz 95.75MHz
2 97.25MHz 101.75MHz
3 103.25MHz 107.75MHz
4 171.25MHz 175.75MHz
5 177.25MHz 181.75MHz
6 183.25MHz 187.75MHz
7 189.25MHz 193.75MHz
8 193.25MHz 197.75MHz

9 199.25MHz 203.75MHz
10 205.25MHz 209.75MHz
11 211.25MHz 215.75MHz
12 217.25MHz 221.75MHz

fs -fv=4.5MHz fs-fv=4.5MHz

CCIR VHF Channel

CH.NO. VideoFrequency Sound Frequency

IF 38.90MHz 33.40MHz

1 41.25MHz 46.75MHz
2 48.25MHz 53.75MHz
3 55.25MHz 60.75MHz
4 62.25MHz 67.75MHz
5 175.25MHz 180.75MHz
6 182.25MHz 187.75MHz
7 189.25MHz 194.75MHz
8 196.25MHz 201.75MHz

9 203.25MHz 208.75MHz
10 210.25MHz 215.75MHz
11 217.25MHz 222.75MHz
12 224.25MHz 229.75MHz

USVHFChannel

CH.NO. VideoFrequency Sound Frequency

IF 45.75MHz 41.25MHz

2 55.25MHz 59.75MHz
3 61.25MHz 65.75MHz
4 67.25Mhz 71.75MHz
5 77.25MHz 81.75MHz
6 83.25MHz 87.75MHz
7 175.25MHz 179.75MHz
8 181.25MHz 185.75MHz

9 187.25MHz 191.75MHz
10 193.25MHz 197.75MHz
11 199.25MHz 203.75MHz
12 205.25Mhz 209.75MHz
13 211.25MHz 215.75MHz

fs -fv=5.5MHz

-3-

2)ChannelSystem and Frequencies

VHF (MHz) UHF (MHz)

C.C.I.R

China

F.O.T.

O.I.R.T

Italy

Angola

2ch 4ch 5ch 12ch

48.25 62.25

1ch 5ch

49.75 85.25

1ch 5ch 6ch 12ch

49.75 93.25 175.25 223.25

Ach Cch Dch H2ch

53.75 82.75 175.25 224.25

1ch 3ch 4c h 10ch

43.25 60.25 175.25 223.25

175.25 224.25

6ch 12ch

168.25 216.25

4ch 12ch

175.25 215.25

21ch 69ch

471.25 855.25

13ch 24ch 25ch 57ch

471.25 863.25

21ch 69ch

471.25 855.25

21ch 69ch

471.25 855.25

21ch 69ch

471.25 855.25

21ch 69ch

471.25 855.25

Australia

Ireland

Morocco

NewZealand

SouthAfrica

0ch 5ch 5Ach 11ch

46.25 102.25 138.25 216.25

Ach Cch

45.75 61.75 175.25 215.25

1ch 3ch

45.25 62.25 175.25 210.25

Dch Ich

4ch 10ch

163.25 211.15

4ch 9ch

4ch 12ch

175.25 247.25

-4-

28ch 69ch

527.25 814.25

21ch 69ch

471.25 855.25

21ch 69ch

471.25 855.25

21ch 69ch

471.25 855.25

21ch 69ch

471.25 855.25

World TV Broadcast System

EUROPE AFRICA ASIA

COUNTRY Broadcast System Color Casio COUNTRY Broadcast System Color Casio COUNTRY BroadcastSystem Color Casio

VHF UHF System Model VHF UHF System Model VHF UHF System Model
Albania B G PAL I Zaire K1 - SECAM W Vietnam D/M - SECAM F
Austria B G PAL C Zambia B - PAL C NEAR & MIDDLE EAST
Belgium B H PAL C AMERICA Afghanistan B - PAL C
Bulgaria D K SECAM W Argentina N - PAL H Bahrain B - PAL C
Czechoslovakia D K SECAM W Barbados M - NTSC B Cyprus B G SECAM F
Denmark B G PAL C Bermuda M - NTSC B Iran B - SECAM F
Germany B G PAL N Bolivia M - NTSC B Iraq B - SECAM F
Finland B G PAL C Brazil M M PAL G Israel B G PAL C
France E/L L SECAM J Canada M M NTSC K Jordan B G/H PAL C
Gibraltar B G PAL C Chile M - NTSC B Kuwait B - PAL C
Greece B G SECAM F Colombia M - NTSC B Lebanon B - SECAM F
Holland B G PAL C Costa Rica M - NTSC B Oman B G PAL C
Hungary D K SECAM W Cuba M - NTSC B Qatar B - PAL C
Iceland B G PAL C Dominica M - NTSC B Saudi Arabia B G SECAM F
Ireland A/I I PAL Y Ecuador M - NTSC B Syria B - SECAM F
Italy B G PAL I El Salvador M - NTSC B Turkey B - PAL C
Luxembourg B G PAL C Guadeloupe K1 - SECAM W United Arab Emirates B - PAL C
Malta B H PAL C Guatemala M - NTSC B Yemen B - PAL C
Monaco G L/G SECAM/PAL - Guyana K1 - SECAM W OCEANIA
Norway B G PAL C Haiti M - NTSC B American Samoa M - NTSC B
Poland D K SECAM W Hawaiian IS. M - NTSC B Australia B G PAL M
Portugal B G PAL C Honduras M - NTSC B Guam M - NTSC B
Romania D K PAL W Jamaica M - NTSC B New Caledonia K1 - SECAM W
San Marino B G PAL I Mexico M M NTSC B New Zealand B - PAL C
Spain B G PAL C Nicaragua M - NTSC B Tahiti K1 - SECAM W
Sweden B G PAL C Panama M - NTSC B
Switzerland B G PAL C Paraguay N - PAL H
UK - I PAL D Peru M - NTSC B
USSR D K SECAM W Puerto Rico M M NTSC B
Yugoslavia B G PAL C ST. Kitts-Nevis M - NTSC B

AFRICA Surinam M - NTSC B
Algeria B - PAL C Trinidad & Tobago M - NTSC B
Burkina Faso K1 - SECAM W Uruguay N - PAL H
Canary IS. B G PAL C USA M M NTSC B
Congo D - SECAM W Virgin IS. M - NTSC B
Cote D'ivoire K1 - SECAM W Venezuela M - NTSC B
Djibouti K1 - SECAM W ASIA
Egypt B - PAL C Brunei B - PAL C
Ethiopia B - PAL C Cambodia M - NTSC B
Gabon K1 - SECAM W China D D PAL E
Ghana B - PAL C Democratic People's D - PAL E
Kenya B - PAL C Republic of Korea
Liberia B - PAL C Hong Kong - I PAL D
Libya B - SECAM F India B - PAL C
Madagascar K1 - SECAM W Indonesia B G PAL C
Morocco B - SECAM F Japan M M NTSC A
Niger K1 - SECAM W Malaysia B - PAL C
Nigeria B G PAL C Mongolia D - SECAM W
Senegal K1 - SECAM W Pakistan B - PAL C
Sierra Leone B - PAL C Philippines M M NTSC B
Sudan B - PAL C Republic of Korea M M NTSC B
South Africa I I PAL *Y Singapore B - PAL C
Tanzania B/I I PAL C Sri Lanka B - PAL C
Tunisia B - SECAM F Taiwan M M NTSC B
Uganda B PAL F Thailand B - PAL C

-5-

Casio TV Model

Casio Color TV Channel Country Scanning fs(audio)-fv(video) Color burst Notes
Model System System line

A NTSC M/M JPN Japan 525 4.5MHz 3.58MHz
B NTSC M/M US American Samoa / Antigua and Barbuda / Bahamas / Barbados / 525 4.5MHz 3.58MHz

C PAL B/G,H CCIR Afghanistan / Algeria / Austria / Bahrain / Bangladesh / Belgium / 625 5.5MHz 4.43MHz

D PAL -/I UK Hong Kong / UK 625 6 MHz 4.43MHz
E PAL D/I China/UK Democratic People's Republic of Korea / China / Hong Kong 625 6.5 MHz / 6 MHz 4.43MHz
F PAL/SECAM B/G,H CCIR Cyprus / East Germany / Egypt / Greece / Iran / Iraq / Lebanon / 625 5.5 MHz 4.25/4.40MHZ

G PAL M/M US Brazil / Lao People's Democratic Republic 525 4.5 MHz 3.58MHz
H PAL N/N US Argentina / Paraguay / Uruguay 625 5.5 MHz 3.58MHz

I PAL B/G ITALY Italy / Albania / San Marino 626 5.5 MHz 4.43MHz
J SECAM L/L France France 625 6.5 MHz 4.25/4.40MHz

K NTSC M/M US Canada *plus Casio Model BA 525 4.5 MHz 3.58MHz

L PAL B/G,H CCIR Denmark / Finland / Norway / Sweden *plus Casio Model CA 625 5.5 MHz 4.43MHz

M PAL B/B Australia Australia *plus Casio Model CA 625 5.5 MHz 4.43MHz

N PAL B/G,H CCIR West Germany *plus Casio Model CA 625 5.5 MHz 4.43MHz
P PAL B/G,H,I CCIR/UK Casio Model LA plus DA 625 5.5 MHz / 6MHz 4.43MHz

Q PAL B/G,H,I CCIR/UK Casio Model NA plus DA 625 5.5 MHz / 6MHz 4.43MHz

R PAL B/G,H,I Italy/UK Casio Model IA plus CA plus DA 625 5.5 MHz / 6MHz 4.43MHz
S PAL B/G,H Australia *Australia (except VHF CH 0 and 3-5A) 625 5.5MHz 4.43MHz Selector: I

PAL B/G,H CCIR Casio Model CA 625 5.5MHz
PAL B/G,H ITALY Albania, Italy 625 5.5MHz

PAL B/G,H New Zealand New Zealand (except VHF CH 1) 625 5.5MHz
SECAM B/G,H CCIR Casio Model FA 625 5.5MHz 4.25/4.40MHz
SECAM B/G,H Morocco Morocco (except VHF CH 4 ) 625 5.5MHz

PAL I/I Angora Angora (except VHF CH 1) 625 6.0MHz 4.43MHz Selector: II

PAL I/I Ireland Ireland (except VHF CH A) 625 6.0MHz

PAL I/I UK Hong Kong, U.K. 625 6.0MHz

PAL I/I South Africa South Africa (except CH 11 and 12) 625 6.0MHz

PAL D/D China China (except UHF CH 57) 625 6.5MHz 4.43MHz Selector: III

PAL D/K O.I.R.T North Korea, Romania 625 6.5MHz
SECAM K1/- F.O.T. Benin, Burkina Faso, Brundi, Chad, Congo, Cote D'ivoire, Djibouti, 625 6.5MHz 4.25/4.40MHz

SECAM D/K O.I.R.T Bulgaria Czechoslovakia, Hungary, Mongolia, Poland, U.S.S.R., 625 6.5MHz 4.25/4.40MHz

V PAL M/M US System Selector M: BRAZIL, LAOS 525 4.5MHz 3.58MHz Selector: M

PAL N/N US System Selector N: Argentina, Paraguay, Uruguay 625 4.5MHz 3.58MHz Selector: N

W SECAM K1/- F.O.T. Benin, Burkina Faso, Brundi, Chad, Congo, Cote D'ivoire, Djibouti, 625 6.5MHz 4.25/4.40MHz

SECAM D/K O.I.R.T Bulgaria Czechoslovakia, Hungary, Mongolia, Poland, U.S.S.R., 625 6.5MHz 4.25/4.40MHz

Y PAL B/G,H Australia *Australia (except VHF CH 3-5A) 625 5.5MHz 4.43MHz Selector: I

PAL B/G,H CCIR Casio Model CA 625 5.5MHz

PAL B/G,H Italy Albania, Italy 625 5.5MHz

PAL B/G,H New Zealand New Zea land (except VHF CH 1) 625 5.5MHz
SECAM B/G,H CCIR Casio Model FA 625 5.5MHz 4.25/4.40MHz
SECAM B/G,H Morocco Morocco (except VHF CH 4 and 5 ) 625 5.5MHz

PAL I/I Angora Angora (except VHF CH 1) 625 6.0MHz 4.43MHz Selector: II

PAL I/I Ireland Ireland 625 6.0MHz

PAL I/I UK Hong Kong, U.K. 625 6.0MHz

PAL I/I South Africa South Africa (except CH 11 and 13) 625 6.0MHz
SECAM L/L France France (except CH A) 625 6.5MHz 4.25/4.40MHz Selector: III

Belize / Bermuda / Bolivia /Cambodia / Chile / Colombia /
Costa Rica / Cuba / Dominican Republic / Ecuador / El Salvador /
Guatemala / Haiti / Honduras / Jamaica / Mexico / Micronesia /
Netherlands Antilles / Nicaragua / Panama / Peru / Philippines /
Puerto Rico / Saint Christopher & Nevis / Saint Lucia /
South Korea / Surinam / Taiwan / Trinidad and Tobago /
Union of Myanmar / U.S.A. / Venezuela

Brunei / Central African Republic / Equatorial Guinea / Ethiopia /
Ghana /Greenland / Holland / Iceland / India / Indonesia /
Jordan / Kenya / Kuwait / Liberia / Luxembourg / Malaysia /
Maldives / Malta / Mozambique / New Zealand / Nigeria / Oman /
Pakistan / Portugal / Qatar / Seychelles / Sierra Leone /
Singapore / Spain / Pakistan / Portugal / Qatar / Seychelles /
Sierra Leone / Singapore / Spain / Sri Lanka / Sudan / Swaziland /
Switzerland / Tanzania / Thailand / The Yemen Arab Republic /
Turkey / United Arab Emirates / Yugoslavia / Zambia
*Australia (except VHF CH 3-5A)

Libya / Mauritania / Mauritius / Morocco / Saudi Arabia / Syria /
Tunisia / Uganda / Vietnam / Zimbabwe
* plus Casio Model CA

Gabon, Guadeloupe, Guiana, Guinea, Guyana, Ivory Coast,
Madagascar, Mali, Martinique, New Caledonia, Niger, Polynesia,
Reunion, ST. Pierre et Miquelon, Senegal, Tahiti, Togo, Zaire,

Vietnam

Gabon, Guadeloupe, Guiana, Guinea, Guyana, Ivory Coast,
Madagascar, Mali, Martinique, New Caledonia, Niger, Polynesia,
Reunion, ST. Pierre et Miquelon, Senegal, Tahiti, Togo, Zaire,

Vietnam

-6-

BLOCK DIAGRAM

VHF, UHF

VHF:Abbreviation for VeryHighFrequency.

Thesendingou t ofradiowavesatthe rateof 30 to 300MHz,Producinggoodsoundquality.

UHF:AbbreviationforUltra High Frequency.

Thesendingou t ofradiowavesatthe rateof 300 to3000MHz, Producingexcellentsoundquality.

Antenna

VHF, UHF

Power
Supply

LinearPCB

TU200 Q200

Tuner IF Amp.

Tuning
Voltage
Generator

Display ass'y

IC200

Video Det.
Sound Det.
FMDet.
AFTCircuit
AGCCircuit

Chroma
Circuit

IC700

OSC.
Display Control
A-DConverter
Auto-tuning

Control

VR IC600

Volume
Control

Common
Drive

Audio
Amp.

LCD

Speaker

VR

Brightness
Control

IC800

Display
Voltage
Generator

Segment Drive

Rod Antenna

Whentherodantennaisnotproperlyadjustment, TVreceptio n isnot getaclear picture( picturemovesup ordown,
disappearsperiodically,becomesfuzzy orblurred,isdoubled,etc.). Inthis case, adjustangleanddirection forbest

reception.
LocationswhereTV receptionisbad.

• Far away from broadcastingstations,amongferro-concrete structuresornearmountains.

• Underground,intunnels orinferro-concrete buildings.

• Near high-tension wires, neonsigns, orradiostationswhose frequenciesinterfere.

• Near railroads, highways or airport.

• In trains or cars.

-7-

Under poor reception conditions,the tuning indicator may continue to move without stoppingbecause the auto tuner
cannot detect weak broadcasts.In this case, usea commercially available externalantenna or relocate the TV to a
place where reception is better.
The user usually damaged the rod antenna. We suggest that you stock this parts.
Model CV-1 is used both as a earphone and an antenna.

PCB Ass'y

Linear PCB

1) Colortuner: TU200
Selects a desired radio wave and changes it to the videoIF signal.

2) Video IF Amp.:Q200
Amplifies the video IF signal output from the tuner by 10 times.

3) Video Det./ SoundDet./ FM Det./ AFT/ AGC: IC200
Eliminates the carrier wave in the video IFsignal, andpick up the video signal and thesound signal.
Also, the sound signal is pickedup from the sound IF signal by FM detection. Automatic fine tuning circuit for
keeping thefrequency of the oscillator in thetuner correct for bestcolor picture bycompensating for drift and
incorrect tuning. Automatic gain control circuitfor avoiding influence of receiving deterioration by wave
strength.

4) Audio Amp.: IC600

Soundamplification.

5) Chroma Circuit: IC300

Generates the tricolor (red,green and blue) from the video signal.

6) Tuning voltage generator: IC500
Generates the tuning voltage from thetuning pulse(TU).

PW PCB: Generates the power supply voltage.

SUB PCB: Generates thepower supply voltage.

RD PCB: Selects adesired radio wave.

Display Ass'y

LCD

Casio LCD television is used two type of LCD drivesystems: HQM and Active matrix.

1) HQM ( SimpleMatrix )
Scanning and segment transparent electrodes are arranged in closed way. To the scanning electrodes,the gate
pulse is applied timesharing. The TVsignal is changed into 4-bit or 3-bit data through A/D conversion (IC700), so
that the TV signalcan be handed with the LSI, and applied to thesegment electrodes.
Structure is simple and price is low, but contrast ratio is low.

2)Active Matrix

Each picture element electrode is controlled by a transistor. To the gate electrodes, thegate pulse is applied
timesharing, like the HQM. I f the gate pulse is applied, the transistors are in operation and voltage is applied
between thepicture electrodes and common electrodes and the liquid crystal reacts allowing the light to transmit.

Structure is complicated and price is high,but contrastratio is high.

-8-

(1) High Quality Matrix

Y1 Y2Y3 Y4 Xn

X1
X2
X3
X4
X5

(2) Active Matrix

Y1 Y2 Y3 Y4

X1

X2

X3

X
n

X4

Back Light: It produceslight and allows the LCD to be seen.

A fluorescent lamp is used this back light, and the life of this unit is to be 1,500 hours.

Power Supply: 3-way power supply system.

Batteries - AA-size or AAA-size (CV-1) dry batteries.

Battery Life:

Type Life
AlkalineLR6 (AM-3) Approx.2 ~3hours
ManganeseR6(UM-3) Approx.15 ~30minutes

AD PCB

1) OSC/ A-D Converter/Display Control/ Auto-Tuning Control: IC700
Converts the color signal into a digital signal. Also, generates the clock pulse for the display and controls the display.

2) Displayvoltage generator: IC800
Generates thedisplay voltage.

Back Light

Placed it under the LCD unitand producing light that TV screen can be seen. A fluorescent lamp is used this back light.
The life is to be 1,500 hours. Newtype of fluorescent lampis to be 3,000 hours. The back light is consumption items,
so even under guarantee replace it under charge basis.

Power Supply

There are 3-way power supply systems.

1) Batteries: AAA-size and AA-size (CV-1)
We recommendto use alkaline batteries.The battery life is approx. 2 to 3 hours with alkaline battery, 15 to30 minutes
with manganese battery.
The battery supplied with TV are test battery which have a shorter life span.
Low battery power generates heat. Heatdoes not mean malfunction.

2)AC adaptor
There are three typeof AC adaptors: 6V, 9V and 12V. The optional AC adaptoris supplied from our sales department.

3)Car adaptor
There are three typeof Car adaptors: 6V, 9V and 12V. The optional car adaptor is supplied from our sales department.

-9-

DC IN: External power source jack. Insert the plug of the AC adaptor or the car adaptorinto this jack.

EXT/ANT.: External antenna jack.Insert the plug of theoptional car antenna intothis jack. Connect the optional antenna

adaptorAS-35S to your outdoor antenna or the optional RF cord CF-13 to your VCR.

AUDIO/VIDEO: Audio video jack. Connect the optional Audiovideo cable cord AV-C1 to your VCR.

-10-

Tuner

CIRCUIT OPERATION

Thetunerselects andamplifies t heincomingAMvideo-modulated andFMsound-modulatedsignalsand
concertsthemtothe intermediate-frequencysignals required by th e IFamplifiers.

Picturecarrier

Antenna

fv

Amplifythechannel
frequencies

Convertthe channelfrequenciestointermediatefrequencies

PictureIF= fosc -fv = 45.75MHz(USchannel)

Sound IF=

fosc-fs =41.25MHz(USchannel)

Input
Circuit

RFAmp.

Selectspecificchannel

Powersupply
voltage

fs

Soundcarrier

BV
BU
BM

AGC

The Automatic Gain Control system
maintainsasubstantially constant
videodetectorpicture outputby
applyinganautomatically varying dc
biasvoltagetothe RF.Inbasic
principle,the AGCsystem in aTV
receiverissimilar toAVC systems
in radioreceivers-itprovidesa
constant-amplitudesignal.

Field-strength is weak

Tuning
Circuit

Local
oscillator

BS

VHFlow andhigh
channelsselecting
voltage.
VHF(L):

Approx.20V
VHF(H):
Approx.0V

Mixing
Circuit

VIF

SIF

fosc

Localoscillatorfrequency

Tuningvoltageinput terminal.A channel

BT

corresponding to the direct voltage to this
terminalisselected,andfrequency
conversionisperformed.

TV-100B TV-100C
VHF(L) 2CH 1.0-2.8(V) 2CH 1.3-3.3(V)
VHF(L) 6CH 17.2-18.8(V) 4CH 6.5-8.5(V)

VHF(H) 7CH 6.4-8.4(V) 5CH 6.1-8.1(V)
VHF(H) 13CH 17.2-18.8(V) 12CH 17.2-18.8(V)

UHF 14CH 1.0-3.4(V) 21CH 0.9-2.3(V)
UHF 69CH 22.4-23.6(V) 69CH 24.4-25.6(V)

Field-strengthis strong

Tuner

AGC for
Tuner

AGC voltage

Video IF
Amp.

AGC for
IF

AGC
Amp.

AGC voltage

Video
DET

AGC DET

Video
Amp.

Noise
elimination

TunerVoltage

BV: Powervoltageforinner VHFcircuit.
BU:Powervoltage for innerUHFcircuit.
BM:Powersupply forinternalmixer.

VHF(L) VHF(H) UHF
BV Approx. 4V Approx. 4V 0V
BU 0V 0V Approx. 4V

BM Approx. 4V Approx.4V Approx.4V

BT 0 - 25V 0 - 25V 0 - 25V
BS Approx.20V 0V 0V

AGC 1.0 - 3.0V 1.0 - 3.0V 1. 0 - 3.0V

-11-

IC200 Video DET., Sound DET., FM DET., AGC, MUTE.

Eliminatesthecarrierwavein the video IF signal, and picks up the videosignalandthe soundIF signal.
Alsothe soundsignalis pickedup fromthesoundIF signal byF Mdetection andcontrolled itsvolumeb y
MUTEvoltage.

Video signal+Sound IF

SIFtrap

ToIC300

SIFtrapremoves
the soundIF.

Discriminator
Picksupthesoundsignal.

SYNC.
SEP

Picksup the synchronizing
pulsefromthevideoIFsignal.

IFAGC
DET.

RF AGC

AGC

The Automatic Gain Control system
maintainsasubstantially constant
videodetectorpicture outputby
applyinganautomatically varying dc
biasvoltagetothe RF.Inbasic
principle,the AGCsystem in aTV
receiverissimilar toAVC systems
in radioreceivers-itprovidesa
constant-amplitudesignal.

Automatic fi n e tuning

AFTblockgenerates th e AFTvoltage

(directvoltage)withadifference of
frequencybetweenth eIFandinput
signalfromthetuner.

Audio Signal

Video Amplifier

Sound Takeoff

Video
DET.

1stand
2nd AMP.

IF signal input

VIF

SIF

Model AFTvoltage
TV-100 2.5+/-0.2V
TV-480 1.7+/-0.2V

SIFfilter

AFT

FM
DET.

Sound
signal

Video

ATT

AMP.

Limiter

SIF

SIFfilter picksupthe
SIF fromvideosignal.

Video detection

Demodulation

Coil connectedt o pinn o.
1 9 and 20 determines
the tuning point of the
LLD detection, and must
b e matched with the
intermediatefrequency.

SIFfilter removesthefs-fvMHzsound
componentfromsound IFsignal.

Buffer

Carrier wave

Videosignal

SoundIF

Limiter-Amplifier

Picksup the soundsignal
fromFMmodulated signal.

U.S.A CCIR U.K. China
SIFfilter 4.5MHz 5.5MHz 6.0MHz 6.5MHz
Discriminator 4.5MHz 5.5MHz 6.0MHz 6.5MHz
SIFtrap 4.5MHz 5.5MHz 6.0MHz 6.5MHz

FMdetection
(Discriminator)

-12-

Limitstheamplitudeof itsoutputsignal to
somepredeterminedthre shol d level.

Thesound iscutoffduring
tuning.Audiosignal iscut
whenpinno. 14 receives
GNDlevel.

ATT

Audio Amplifier

IC300 Chroma Circuit (NTSC)

Generatesthetricolorof red,greenandbluefrom the videosignal.

Y/CSeparator

Color

Videosignal

Band pass Amp.

sub carrier
Trap

isthe amplified
compositecolor
videosignal.

Band pass
filter

Color
adjust

Colorsignal

BurstAmp.separates the color
syncfrom the compositevideo
signal.

Color

adjust
Band
Amp.

Burst
Amp.

Luminancesignal

Hueadjust

Contrastadjust

Contrast
Adjust

B-Ydem­odulation

Ymixer
BAmp.

Blue

Sync
signal

Burst

Hue
adjust

G-Y
Matrix

Ymixer
GAmp.

Generator

Automatic
Chroma
Control

Color
Killer

Automatic
Phase
Control

R-Y dem­odulation

Subcarrier
OSC

Ymixer
RAmp.

Automatic Chroma Control

ACCistoprovideautomatic gain control
for the chroma amplifies.This circuitis
keepingthechromaand burstsignalsa ta
constantlevel.

Color Killer

The color killer keepsthe
band pass amplifiercutoffin

APC

Reinsertsasubcarriersignalwith
exactlythecorrectphaseand
frequencybysynchronizingwith
thetransmittedcolor-burstsignal.

the absenceof acolor signal.

DEMODULATION

The B-YandR-Ydemodulators areeach synchronized essentiallyto sampleth e resultant chrominance
signalECand producetherespectiveB-Yand R-Yvoltage.Afterdemodulation, theB-Yand R-Y signals
enterthematrixstage.The twocolorsignalscombinein the G-Ymatrixwhichproduces th e resultantG-Y
colorsignal,andoutput signals (B-Y, R-Yand G-Y) combinewiththe luminancesignalatthe mixer , then
outputsproportionalvalues ofred,blue, andgreen.

Green

Red

-13-

IC300 Chroma Circuit (PAL)

Generatesthetricolorof red,greenandbluefrom the videosignal.

Y/CSeparator

Videosignal
Colorsignal

Chroma
Trap

4.43MHz

Band pass
filter

SYNC
SEP.

Luminancesignal

Contrastadjust

Sync
signal

ACC

ACC
DET

Burst
GP

Killer

Chroma
OUT

0° and
180°

PAL-SW

PIX
CTR

F/F

PIX CLAMP

PAL/SE­CAMSW

90°

Y-OUT

Contrast
adjust

B Matrix

GMatrix

RMatrix

Blue

B-OUT

Green

G-OUT

Red

R-OUT

R-Y
DEM

B-Y
DEM

Subcarrier
OSC

Phase
Control

Thepointthat NTSC isdifferent from PAL in apart
offrameof bold lines

PAL is basically the same asNTSC.PAL is different from NTSC in the wayof the color signaltransmission.
The phaseofB-Ysignal is fixed90degree.The phaseofR-Ysignalchangesat0and180degreeonevery
horizontalscanningline. Th e 4.43MHz sub carrier is usedtotransmit color information.

-14-

Automatic

IC300 Chroma Circuit (PAL/SECAM)

Generatesthetricolorof red,greenandbluefrom the videosignal.

Video
signal

Y/CSeparator

Chroma
Trap

4.43MHz

Band pass
filter

Sync
SEP.

Luminance
signal

Contrast
adjust

Sync
signal

PAL

Bell filter

4.28MHz

ACC

ACC
DET

Burst
GP

Killer

Color
signal

Chroma
OUT

0° and 180°

R-Y
DEM

Horizontalsync

PIX
CTR

PIX CLAMP

F/F

PAL/SE­CAM SW

90°PAL-SW

B-Y
DEM

Y-OUT

Subcarrier
OSC

Contrast
adjust

BMatrix

GMatrix

RMatrix

Blankingsignal

B-OUT

G-OUT

R-OUT

Automatic
Phase
Control

B-Ysignal
4250000Hz

Blue

Green

Red

R-Y

B-Y

Quadrature
coil4.25MHz

SECAM

Limiter

Gate SW

Onedelay
line

limitsthe
amplitude

direct t o switch(non-delayed signal)

through onedelay line(delayed signal)

line identify

line changeover
interlockswitch

ID

F/F

SECAM
SW

Cleaning

PicksuptheSECAM
colorsignals(B-Y,
R-Y) by FM detectors

Subcarrierfrequency
R-Y signal4406350Hz

4.25MHz
B-Y DEM

R-Y DEM

4.406MHz

Quadrature
coil4.4MHz

ItisdifferenceofSECAM,NTSCand PAL that thefrequencyofR-Y andB-Ysignal aredemodulatedand
transmitted reciprocallyinorderon everyline.

The demodulationofsignalSECAMis separatedfromtwosystems. One system isleddirecttothe linechange
over interlockswitchcircuit, anothersystemisled to the switch circuit throughonedelayline.
Theswitch circuitchangesovert hedelayedsignalof atermscanning lineandnon-delayedsignal, takes out two
colordifferentsignal. Bydetectingin eachFM,R-YandB-Ysignal aregotten.

-15-

IC400 Tuning Voltage Generators

IC400 has 3circuits for converting pulses to voltages, selects one of VHF-L, VHF-H or UHF, and causes the tuning

voltage to be output from OUT terminal.

OUT IN

U/V H/L SWon

L L S2,S5
L H S3,S6
H L S1,S4
H H S1,S4

S3

S2
S1

S6
S5
S4

TU SWon

L S7
H S8

BT

S8

S7

Current
Source

UHF

VCC

U/V
UHF / VHF channels
switching signal.
Input 4V with setting
the select switch to
UHF.

BS

GEN.
CODE
CONV.

U/V H/L BS TU Vref

BS
VHF low / high
channels switching
signal.
Approx. 20V when
the indicatoris at
VHF low channel.

TU

H/L
VHF low / high channels switching

Tuning pulse being
output fromIC700.

signal.
GND level when the indicator is VHF

TU pulse BT voltage

low channel.
Approx. 4V when the indicator is
VHF highand UHFchannel

Vref
GEN.

BT
Tuning voltage.
Tuning pulse is converted into a
DC voltage by theIC400, and
applied to the tuning voltage to
the tuner.

U/V H/L BS BT
VHFL GND GND Approx.20V Approx.0 ~20V
VHFH GND Approx.4V GND Approx.0~ 20V
UHF Approx.4V Approx.4V GND Approx.0~20V

When the Up or Down buttons is pressed, TU pulse becomes
gradually narrower, and thetuning voltage BT is also gradually
decreases.

-16-

IC700

VSS2 TE1 TE2 TE3 TE4 TE5TE6 M6 M5 M4 M3 M2 M1 AFT

AD2
AD1

B
G

R
RLL
VDD2
RHH

M7
M8
M9
M10
PSi

VSS1

A/D

Mode
Control

Data Output

Test Control Mode Control

Channel
Bar
Control

Vertical
Positioning
Control

Frequency
Divider

Tuning Voltage
UP/DOWN Counter

Pulse Width
Modulation D/A

Horizontal
Positioning
Control

Sweep
Control

Phase
Comparator

Frequency
Divider

AFT
Control

Key
Switch
Control

Mute
Control

Synchronism
Judgment

Frequency
Separator

Oscillator

KDB
KCB
AVB
UHF

MTB

VLB

TU

VDD1
C-S

PD

OSC1
OSC2

D1 D2 D3 D4 D5 D6 CDBCFB CNB ECB SNB SCB STB HDB

SignalName Function SignalName Function

D1~ D6 Displaydata output terminal. VLB VHFHigh/Lowchannel selectsignal

SNB Data latch signal. output.
CDB Scanning startsignal. UHF VHF/UHFselectsignal.
CFB Voltage changeover signal. AVB Keyinput.
CNB Scanning Signal shiftlock signal. KCB Key input.
SCB Brightnessmodulationpulse control. KDB Keyinput.
STB Sampling startsignal. AFT AFT voltage input terminal.
ECB

CK1,CK2

OSC1,OSC2 Oscillatorcontrolterminal. RLL Low levelvoltageinput terminalof

PD

C-S Sync pulseinput. RHH High levelvoltageinput terminalof

HDB

VDD1 VDD voltage input. PS1 Mode controlsignal.

MTB

TU Tuning controlpulse output.

Controlthe segment drive terminal. M1~M10 Mode select signalinput terminal.
"H" levelduring no display. TE1~ TE6 Test terminal.
Clockpulse output terminal. R,G, B Colorsignal.

Clockpulse adjustmentterminal. video signal.

HorizontalSync signalinput. video signal.

Mute controlterminal. VSS1 Power supplyvoltageinput.

CK1 CK2

-17-

Tuning Operation
(NTSC)

UP orDown

button

PD

Oscillator

OSC1,OSC2

Frequency
Divider

Horizontal
Positioning
Control

TO
LCD

Vertical

PositioningControl

IC700

AFT Control

PulseWidth
Modulation

BU

BTGenerator

UHF Tuning
Circuit

UHF Mixing
Circuit

Synchronism

Key Switch
Control

Sweep
Control

Tuning voltage
control

TU

H/L

BSGenerator

Local
Oscillator

VHF Mixing
Circuit

VLB

H/L

IC400

VHFTuning
Circuit

A/D

Convertor

Channel Bar
Control

Mute
Control

IF AMP. SAW Filter

MTB

Data Output

Local
Oscillator

Power Switch

UHF

VHF/UHF
RF AMP.

IF AGC

Judgment

VCC1 Back Light

UHF or
VHF

VHF

BackLight
Circuit

VHF/UHF
InputCircuit

TUNER

IC200

Frequency
Separator

Phase
Comparator

Power Supply
Circuit

Batteriesor AC Adaptor

Antenna

Video DET.AFT

Video AMP. SIF Filter Limiter FM DET ATT

Burst
Generator

3.58MHz Trap

Band pass
Filter

Contrast

Adjust

Band AMP. Burst AMP.

ACC

Color Killer

1stAMP.2nd AMP.

IC300

Color Adjust

HueAdjust

Automatic
PhaseControl

3.58MHzOSC

Buffer AMP.SIF Trap SYNC. SEP

B-Y Demo­dulator

G-YMatrix

R-Y Demo­dulator

Y Mixer
Blue AMP.

Y Mixer
Green AMP.

Y Mixer
RedAMP.

B

G

R

-18-

Adjustment

Casio gives another through adjustment before TVs are put on the market. There's usually no
need for you to adjust the TVs except VCC voltage setting when repaired the power supply
circuit and VCOM adjustment whenever replaced the TFT LCD.
The other adjustments, it is necessary to have the expensive equipment's. When appropriate
equipment's are not available, we recommend to replace the Linear PCB ass'y.

The full details of adjustments, refer to each of service manuals.

Main Adjustment Points Outline Equipment

VCC Voltage Setting Set the voltage VCC. If set value is wrong, Power supply

malfunction or increasing consumed current. Voltmeter
Be sure to adjust it.

Video Detection Coil Adjustment No reception is possible at all or the sensitivity is Power supply

extremely bad when replaced IC200 or video det- Pattern generator
ection coil, be sure to adjust the video detection Signal generator
coil. Oscilloscope

Low-pass filter

AFT Coil Adjustment No reception is possible at all or the sensitivity is Power supply

extremely bad when replaced IC200 or AFT coil, Pattern generator
be sure to adjust the AFT coil. Signal generator

Oscilloscope
Voltmeter

PD Voltage Adjustment No synchronization is gained. Power supply

Pattern generator
Signal generator
Voltmeter
IF levelmeter

Contrast Adjustment Make this adjustment when contrast is not good. Power supply

Pattern generator
Signal generator
Oscilloscope

Tint Volume Adjustment When replacing IC300 or tint volume, be sure Power supply

to adjust the tint volume. Pattern generator

Signal generator
Oscilloscope

AGC Adjustment No reception is possible at all or the sensitivity is Power supply

extremely bad when replaced T200 or IC200, be Pattern generator
sure to adjust the video detection coil. Signal generator

Oscilloscope

IF levelmeter
Free-Running Frequency No synchronization is gained. Power supply
Adjustment Frequency Counter
VCOM Adjustment Make this adjustment whenever replacing the Power supply
(TFT LCD only) LCD or when the LCD is flickered. Pattern generator

Signal generator

Oscilloscope

Photo diode

-19-

1. No power

Check fuse.

Is fuseblown up?

NO

TROUBLESHOOTING

YES

Replace fuse.

Measure output

voltage of DC-DC

convertor.

Is voltage

VCC2 +4V

DC?

NO

YES

• Replace LCD unit.

• Replace inverter transformer or
transistor(s) on power supply for
back light.

• Replace coil and capacitor on
power supply for back light.

A

• Check power switch.

• Check poorsoldering on
power supply block.

Is itOK?

NO

YES

• Replace all of transistor Q100,
Q101 andQ102 on power
supply block.

• Replace DC-DC convertor.

Replace power
switch or resolder.

-20-

2. Sound heard, but no picture

Check temperature fuse.

Is fuse

blown up?

NO

YES

Replace

fluorescent

lamp.

Is apicture

OK?

YES

NO

• Check poorsoldering on
power supply for back light.

• Replace Inverter transformer
or transistor(s) on power
supply for back light

Replace fuse.

END

3. Picture all green

Replace LCD

unit.

Is apicture

OK?

NO

A

YES

END

-21-

4. No picture and high current consumption.
Burning a transistor(s) on power supply.

Replace DC-DC

convertor

Are pictureand

current

consumption

OK?

YES

NO

Replace allof transistor
on power supply block.

5. Picture all green and high current consumption.
Burning a transistor(s) on power supply for back light.

Replace inverter

transformer.

END

Are pictureand

current

consumption

OK?

NO

• Replace all of transistor
on power supply for back
light.

• Replace Coil and capacitor
on power supply for back
light.

YES

END

-22-

6. No sound

Measure the
audio signal.

Does the audio

signal output of

audio amp.?

NO

YES

Check the wire of

•

speaker.
Replace speaker.

•

Does the audio

signal appear at
IC200(AUDIO)?

• Check the soldering around IC200.

• Replace IC200.

7. A certain button does not function

Check the switch.

pin 13of

NO

YES

• Check the soldering

around audio amp.

• Replace audio amp.

Is switch

defective?

NO

• Check the soldering around
switch.

• Check the circuit between

IC700 and switch.

• Replace IC700.

-23-

YES

Replace the

switch.

8. Automatic tuning doesn't stop.

collector waveform

20µs

Varies between

20 to 50mV

Measure the

of IF amp.

120mV

Figure 1

Is the

waveform like

that shownin

Fig. 1?

NO

Are BM,BV

and BU of

tuner voltage

4V?

YES

Check BS of tuner
voltage ina channel of
L andH of VHF.

YES

NO

B

• Check the circuit between

switch and tuner.

• Replace switch.

Is BSvoltage

21V at VHF L

channel?

YES

Is BSvoltage

GND level at

VHF H

channel?

YES

-24-

NO

NO

Check the voltage at pin
no. 10 (H/L) of MSC1169.

DC

B

Replace IC200.

YES

Is the waveform at

pin no. 18 of IC200

like that shown in

Fig. 2 when the

indicator passes

the receiving

YES

Is AFT(at pin no.

17 of IC200)
voltage 0to 4V
While Indicator

moves?

YES

20µs

0.5V

NO

Figure 2

NO

20µs

2V

Figure 4

Is the waveform
at pin 19 and 20

of IC200 like that

shown Fig.3?

Replace IC200.

20µs

10mV

NO

Figure 3

• Check the poor

soldering on all
line of IC200 and
MSC1169.

• Replace IC200.

Varies between

20 to 50mV

Is SyOUT(at pin

no. 23 of IC200)

like that shown

Fig. 4?

YES

Is the waveform of R,

G andB like that

Fig. 5 when the

indicator passes the

receiving channel ?

0.1µs

YES

E

0.2V

NO

20µs

0.5V

NO

Figure 6

Figure 5

Replace IC200.

Is anAV jack

OK?

NO

Replace AVjack.

-25-

YES

Replace H300.

NO

Is the

waveform

of H300 like

that shown

Fig. 6?

YES

• Check the circuit between
IC200 andIC300.

• ReplaceIC300.

C

Check BT of tuner
voltage ina
channel of VHF.

Is BT voltage

0 to 21V at

VHF channel?

YES

Is the tuner

voltage AGC

1.0 to 1.2V?

NO

NO

5µs

1V

Replace IC200.

Figure 7

Is the waveform

at pin no. 11(TU)
of MSC1169 like

that shownin Fig.7?

NO

YES

Replace MSC1169.

YES

Does 4Vappear

at pin no. 9(H/L) of

MSC1169 at

UHF?

NO

YES

Replace tuner.

• Check the circuit

between MSC1169

and IC700.

• Replace IC700.

.• Check the circuit between

switch andMSC1169.

• Replace Switch.

-26-

D

IS H/L 4V

at VHF L channel?

NO

IS H/L voltage

GND level at

VHF H channel?

NO

• Check the circuit between

MSC1169 andIC700.

• Replace IC700.

YES

YES

Replace MSC1169.

Check the circuit
between IC300and
IC700.

NO

E

YES

Do C-S,AFT

and R-G-B

pulse appear

on IC700?

YES

50ns

5V

Figure 8

Check the poor

•

soldering on
OSC b lock.

Replace IC700.

•

-27-

NO

Is the waveform

at pin no. 17of

IC700 (OSC)like

that shownin

Fig. 8?

YES

Replace LCDunit.

Trouble example

TV-7

No picture FL replaced

No sound Battery replaced
No tuning Battery replaced

TV-100

No picture FL replaced

No sound Battery replaced

Bright volume doesn't work Defective R825
Picture all green Short circuit joint on lead of capacitor C105
Indicator does not stop Poor soldering joint on lead of capacitor C303

No tuning when the RF signal is Defective IC200
under 55dBµ
Tuning is OK, but erratic display Defective capacitor C205 & C808
Indicator does not stop Defective capacitor C205 & C808
when the RF signal is strong

Symptoms Causes

Temperature fuse replaced
Power switch replaced
Fuse replaced
Battery replaced

Defective speaker

Symptoms Causes

LCD replaced
DC jack replaced
Fuse replaced
Poor soldering

Speaker replaced
Poor soldering on IC

Poor soldering joint on terminal pin 17 of IC700
Broken resistor R703
Defective capacitor C205 & C808
Defective F200

TV-160

Symptoms Causes

No picture Fuse replaced

Battery replaced

LCD replaced
No sound Speaker replaced
Indicator does not stop Battery replaced

LCD replaced
Specific channel does Speaker replaced
not receive LCD replaced

Speaker replaced
Poor reception or LCD replaced

picture dark FL replaced

-28-

SCHEMATIC DIAGRAM & WAVEFORMS

AV Jack

Power
Jack

Batteries

NTSC

EXT
Jack

Power supply
circuit

Fuse

Antenna

TUNER

BU

UHF input
circuit

ANT

VHF input
circuit

Power
switch

BU(4V)

BV(4V)

U/V

IC300
Croma circuit

FSC APC ACC TINT

APC

VCO

VXOUT

7

VXOF Killer F KO YIN PIX

X'tal

UHF RF
Amp.

VHF RF
Amp.

BV

UHF tuning
circuit

VHF tuning
circuit

VHF local
oscillator

AGC 1.0‘ 3.0V

IC400

Tuning voltage generator

AMP.

S3
S2
S1
S6
S5
S4

CODE
CONV.

TINT

AMP.

U/V H/L SW ON
L L S2, S5
L H S3, S6
H L S1, S4
H H S1, S4

H/L

CIN G

ACC
Color

BURST
GATE

KILLER

BS
GEN.

S7

BS

12

11

OUT

S8

TU

R-Y
DET.

PIX

8

UHF local
oscillator

UHF mixing
circuit

VHF mixing
circuit

IN

TU SW ON
L S7
H S8

Vref
GEN.

Vref

R

MATRIX
(CONTRAST)

G-Y
DET.

Cont

VCC2

Current
Source

CLAMP

Cont OUT

10

B

B-Y
DET.

IF output

BS(0/20V)
BT(0‘ 21V)

BT

C-SY

GATE
GEN.

BGPW

9

1

IF Amp.

IC200
Video DET., Sound DET., FM DET., AGC, AFT and Mute

4

5

SYNC.

SAW filter

1

F200

2

IC700 OSC, A-D converter, Display control Auto-Tuning control

VSS2 TE1

A/D

Mode
control

Data Output

D1D2 D3

D4D5D6

TE4 TE6

TE2

TE3

Test control

Channel bar
control

TE5

SEP

IF AGC
DET.

RF AGC
(Forward)

M6 M5 M4 M3 M2 M1 AFT

Mode control

Frequency
divider

Vertical
positioning
control

CDB

CFB

LLDAFT

VIDEO
DET.

Sweep
control

Tuning voltage
Up/Down counter

Pulse width
modulation D/A

Horizontal
positioning
control

CNB

SNB

3

2

SCB

4.5MHz

2nd
AMP.

1st
AMP.

AFT
control

STB

AFT

4.5MHz

VIDEO
AMP.

Phase
comparator

Frequency
divider

FM
DET.

Mute
control

Synchronism
judgment

CK2CK1HDB

4V

FM detection

ATT

LIMITER

Key
switch
control

Frequency
separator

Oscillator

VC

BUFFER

KDB

KCB
AVB
UHF

MTB

VLB

TU

C-S

PD
VDD1

OSC1

OSC2

CDB
CFB

CNB

IC703

6

Amp.

Earphoen
Jack

SIF filter

4.5MHz

STB

CK2CK1

S1 S359

C1

C110

S2 S360

CK1

CK2

STB

Speaker

SNB

LCD

SNB

3V

IC702

D1~D3

D4~D6

IC701

-29-

AV Jack

PAL

4.5, 5.5, 6.0 or 6.5MHz

Ceramic discriminator

FM
DET.

VIDEO
AMP.

SIF IN

FM detection

FMD

ATT

LIMITER

6

AUDIOATTSIF OUT

Speaker

Amp.

Earphoen
Jack

BUFFER

SIF filter

4.5, 5.5, 6.0 or 6.5MHz

EXT
Jack

Antenna

BU

ANT

Power
switch

TUNER

UHF input
circuit

VHF input
circuit

BU(4V)
BV(4V)

UHF RF
Amp.

VHF RF
Amp.

BV

UHF tuning
circuit

VHF tuning
circuit

VHF local
oscillator

AGC 1.0‘ 3.0V

UHF local
oscillator

UHF mixing
circuit

VHF mixing
circuit

VCC2

IF output

BS(0/20V)
BT(0‘ 21V)

1

IF Amp.

VHF L 20V
VHF H, UHF 0V

SAW filter

1
2

F200

IC200

4

SYIN

IF AGC

5

SYOUT

4.5, 5.5, 6.0 or 6.5MHz

LLDAFT
LLD

3

2

AFTC

SIF trap

AFT

VIDEO

ADJ

SYNC.
SEP

AFT

VIDEO
DET.

IF AGC
DET.

2nd
AMP.

IF AGC
OUT

IF AGC
IN

RF AGC
(Forward)

RF AGC

IF IN

1st
AMP.

IF IN

Power
Jack

Batteries

Power supply
circuit

Fuse

4.43MHz

IC300

IDF KIL.O

IDENT

PAL/
SECAM SW

B-Y
(S)

CODE
CONV.

Chroma
trap

YIN

KIL.F

KILLER

CW
INV.

PAL-SW 90

C

R-Y

(R-Y)

(S)

IC400

S3
S2
S1
S6
S5
S4

H/LU/V

VHF L 0V
VHF H, UHF 20V

8

PIX

PIX
CTRL

PIX

R-Y
DEM

C­OUT

AMP.

AMP.

U/V H/L SW ON
L L S2, S5
L H S3, S6
H L S1, S4
H H S1, S4

BS
GEN.

11

CIN

COLOR

Y-OUT

CLAMP

B-Y
DEM

C

VXOF X'TAL VXO

(B-Y)

S8

S7

BS

12

SYNC
SEP.

G-OUT R-OUT

G MATRIX

CHROMA
OUT

VCO

7

INOUT

TU SW ON
L S7
H S8

Current

Source
Vref
GEN.

Vref

TU

G

R

R MATRIX

ACC

APC

FSC APC ACC BCC

OUT

10

CONT

B

OUT

B-OUT

B MATRIX

ACC
DET.

BT

HD CONT

C-SY

F/F

CONT
RASR
CTRL

BGP

9

BGPW

IC700

VSS2 TE1

Mode
control

A/D

D1D2 D3

TE2

Test control

Data Output

D4D5D6

TE4

TE3

Channel bar
control

TE6

M6 M5 M4 M3 M2 M1 AFT

TE5

Mode control

Frequency
divider

Sweep
control

Tuning voltage
Up/Down counter

Pulse width
modulation D/A

Horizontal
positioning
control

CDB

Vertical
positioning
control

CNB

SNB

CFB

SCB

STB

AFT
control

HDB

Phase
comparator

Frequency
divider

Mute
control

Synchronism
judgment

CK2CK1

4V

Key
switch
control

Frequency
separator

Oscillator

VC

KDB

KCB
AVB
UHF

MTB

VLB

TU

C-S

PD

VDD1

OSC1
OSC2

CDB
CFB

CNB

IC703

STB

CK2CK1

S1 S359

C1

C110

S2 S360

CK1

CK2

STB

SNB

LCD

SNB

3V

IC702

D1~D3

D4~D6

IC701

-30-

SECAM

Power
Jack

Batteries

EXT
Jack

Power supply
circuit

Fuse

Antenna

BU

ANT

Power
switch

BU(4V)

BV(4V)

4.43MHz



IC300 (PAL)

IDF KIL.O KIL.F

PAL/
SECAM SW

B-Y
(S)

TUNER

UHF input
circuit

VHF input
circuit

Chroma
trap

KILLER

IDENT

CW
INV.

R-Y
(S)

UHF RF
Amp.

VHF RF
Amp.

IC500

AMP.

S3
S2
S1
S6
S5
S4

CODE
CONV.

H/LU/V

VHF L 0V
VHF H, UHF 20V

8

YIN

PIX

PIX
CTRL

PIX

PAL-SW 90

R-Y
DEM

C-

C

OUT

(R-Y)

BV

AGC 1.0‘ 3.0V

AMP.

U/V H/L SW ON
L L S2, S5
L H S3, S6
H L S1, S4
H H S1, S4

BS
GEN.

11

CIN

COLOR

Y-OUT

CLAMP

B-Y
DEM

C

VXOF X'TAL VXO

(B-Y)

UHF tuning
circuit

VHF tuning
circuit

VHF local
oscillator

S8

S7

BS

12

SYNC
SEP.

G-OUT R-OUT

G MATRIX

CHROMA
OUT

VCO

7

UHF local
oscillator

UHF mixing
circuit

VHF mixing
circuit

VCC2

INOUT

TU SW ON
L S7
H S8

Current

Vref
GEN.

TU

G

OUT

Source

Vref

R

R MATRIX

ACC

APC

FSC APC ACC BCC

10

CONT

B

OUT

B-OUT

B MATRIX

ACC
DET.

IF output

BS(0/20V)
BT(0‘ 21V)

BT

HD

F/F

1

IF Amp.

C-SY

CONT
RASR
CTRL

BGP

9

SAW filter

1
2

VHF L 20V
VHF H, UHF 0V

CONT

BGPW

F200

5.5 or 6.5MHz

Ceramic discriminator

FM
DET.

VIDEO
AMP.

FM detection

FMD

ATT

AV Jack

AUDIOATTSIF OUT

Amp.

6

Speaker

BUFFER

LLDAFT
LLD

5.5 or 6.5MHz

3

2

VIDEO

2nd
AMP.

SIF trap

AFT

AFT

4

IC200

IF AGC
ADJ

SYOUT

IF AGC
DET.

5

SYIN

SYNC.
SEP

AFTC

VIDEO
DET.

Earphoen

IF AGC
OUT

RF AGC
(Forward)

IF AGC
IN

Quadrature
coil 4.25MHz

RF AGC

IF IN

IC700

1st
AMP.

IF IN

VSS2 TE1

A/D

Mode
control

Data Output

D1D2 D3

TE2

TE3

Test control

D4D5D6

SIF IN

TE4

TE6

TE5

Channel bar
control

CDB

LIMITER

M6 M5 M4 M3 M2 M1 AFT

Mode control

Frequency
divider

Tuning voltage
Up/Down counter

Pulse width
modulation D/A

Vertical
positioning
control

CNB

SNB

CFB

AFT
control

Sweep
control

Horizontal
positioning
control

SCB

STB

Frequency
divider

HDB

Jack

SIF filter

5.5 or 6.5MHz

Mute
control

Phase
comparator

CK2CK1

4V

Key
switch
control

Synchronism
judgment

Frequency
separator

Oscillator

VC

KDB

KCB
AVB
UHF

MTB

VLB

TU

C-S

PD
VDD1

OSC1

OSC2

CDB
CFB

CNB

IC703

STB

CK2CK1

S1 S359

C1

C110

S2 S360

CK1

CK2

STB

SNB

LCD

SNB

3V

IC702

D1~D3

D4~D6

IC701

Bell filter

4.28MHz

IC400(SECAM)

One delay
line

B.G.P.

Delay

BGPW C-OUT

SW

BP2

SECAM
CIN

Gate

C-SY

ID

BP1

Limiter ID

Killer

DL CIN

DL CIN

DF4BLKPAL CIN HD

4.25MHz

FF

SECAM
SW

-

+

COLOR

Cleaning

DF1

4.406MHz

Quadrature
coil 4.4MHz

B-Y Det

R-Y Det

DF2 R-Y KIL.F

KIL.OB-YDF3

-31-

Waveforms

1

20µs20µs

2

120mV

3 4

10mV

5 6

20µs

20µs20µs

0.5V

20µs

0.2V

2V

7 8

0.2V

0.1µs

-32-

0.5V

20µs

0.1V

Waveforms

9 10

2V

20µs20µs

20µs

1211

0.5V

5µs

50mV

1V

-33-

CASIO COMPUTER CO., LTD.

SERVICE DIVISION

8-11-10, Nishi-Shinjuku

Shinjuku-ku, Tokyo 160, Japan

Telephone: [phone]

Printer in Japan