Casio TV1800X Service Manual

R

(without price)

TV-1800C(PAL B / G,H)
TV-1800D(PAL I)
TV-1800I (PAL B / G)
TV-1800N(PAL B / G,H)

(KX-523)

DEC. 1996

<

TUNING

>

CONTENTS

Page

SPECIFICATIONS.....................................................................................1

BLOCK DIAGRAM.................................................................................... 2

CIRCUIT OPERATIONS ...........................................................................3

PRINTED CIRCUIT BOARDS...................................................................4

PARTS LIST.............................................................................................. 6

EXPLODED VIEW.....................................................................................9

SCHEMATIC DIAGRAMS.......................................................................11

WAVEFORMS ......................................................................................... 14

SPECIFICATIONS

Item Specification

1. Power voltage DC 6.0 V

2. Power consumption Approx. 3.6 W

3. Current consumption Approx. 600 mA

4. Battery life (with alkaline batteries) Approx. 2.5 hours

Batteries : 4 × LR6 (D) size batteries

5. Power supply Car adaptor : CA-K65
AC adaptor : AD-K65

Earphone jack : 3.5 ø mini

6. Connection terminals External power jack : 6.0 V DC IN
External antenna jack : 3.5 ø mini

7. Screen size 2.5 inches

8. No. of picture element 115,020 (540 × 213) dots

9. Dimensions 135 mm (H) × 91 mm (W) × 38 mm (D)

10. Weight 240 g without batteries

AC adaptor : AD-K65

11. Options Car adaptor : CA-K65
Antenna matching device : AS-35S

Model Color System TV System Channel

TV-1800C/N PAL B/G, H CCIR VHF: 2 ~ 12 ch UHF: 21 ~ 69 ch

TV-1800D PAL –/I UK — UHF: 21 ~ 68 ch

TV-1800I PAL B/G ITALY VHF: A ~ H2 ch UHF: 21 ~ 69 ch

— 1 —

Antenna

BLOCK DIAGRAM

Power
Supply

1 TU200 2 Q200

IF Amp.Tuner

7

IC500

Tuning
Voltage
Generator

VCC2 (3.95V)
VCC7 (41.6~51.6V)
VEE1 (-6.5~-8.0V)

VR800

Brightness
Control

3 IC200

Video
Sound Det. 
FM
AFT Circuit
AGC Circuit

5

6

Osc.
Display
Control
A-D Converter
Auto-Tuning
Control

8 Q800~Q806

Det

IC300

Chroma
Circuit

IC700

Display
Voltage
Generator

VR600

Volume
Control

4 IC600 Speaker

Audio
Amp.

Common
Driver

LCD

Segment
Driver

1 — Color Tuner: TU200 TEPE5-01(TV-1800C/I/N) TU200 TEPB5-05(TV-1800D)

Selects a desired radio wave and changes it to the video IF signal.

2 — Video IF Amp.: Q200 2SC4238

Amplifies the video IF signal output from the tuner TU by 10 times (20 dB).

3 — Video Det./Sound Det./FM Det./AFT/AGC: IC200 M51348FP

Eliminates the carrier wave in the video IF signal, and picks up the video signal and the sound IF signal.
Also, the sound signal is picked up from the sound IF signal by FM detection.

4 — Audio Amp.: IC600 NJM2070M

Sound amplification.

5 — Chroma Circuit: IC300 M52045FP

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

6 — OSC/A-D Converter/Display Control/ Auto-Tuning Control : IC700 MSM662501 GSK-640E

Converts the color signal into a digital signal.
Also, generates the clock pulse for the display and controls the display.

7 — Tuning Voltage Generator: IC500 MSC1169MS-K

Generates the tuning voltage with the tuning pulse (TU) output from 6.

8 — Display Voltage Generator: IC800 BA10358F, Q800 ~ Q806 Q810 Q811 2SD1149S,

2SD601A-R×3, 2SB709A-R
Generates the display voltages V0 ~ V4 with VEE1 and VCC7 outputs from the power supply.

— 2 —

CIRCUIT OPERATIONS

AD2
AD1

RLL

VDD2

RHH

M7
M8
M9

M10

PSi

VSS1

IC700

B
G
R

VSS2 TE1

A/D

Mode

Control

Data Output

TE2

TE4

TE5

TE6

M6 M5 M4 M3 M2 M1 AFT

Frequency

Divider

Channel
bar
Control

Vertical

positioning

Control

TE3

Test Control Mode Control

Test

Circuit

Display
Control

Sweep

Control

Tuning Control

Tuning Voltage
UP/DOWN Counter

Pulse Width
Modulation D/A

Horizontal

positioning

Control

AFT

Control

Phase

Comparator

Frequency

Divider

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 CDB CFB CNB ECB

Signal Name

Function

SCB STB HDB CK1 CK2

SNB

Signal Name

Function

D1 ~ D6 Display data output terminal MTB Mute control terminal

SNB Data latch signal TU Tuning control pulse output terminal

CDB Scanning start signal VLB VHF High/Low channel select signal

output terminal
CFB Output voltage changeover signal UHF VHF/UHF select signal
CNB Scanning signal shift lock signal AVB

KCB Key input terminal
KDB

SCB Brightness modulation pulse control AFT AFT voltage input terminal

STB Sampling start signal M1 ~ M10 Mode select signal input terminal

ECB Signal input terminal controlling the

TE1 ~ TE6

Test terminal

segment drive terminal to "H" during
no display

CK1, CK2 Clock pulse output terminal R, G, B Original color

OSC1 Oscillator frequency control terminal RLL "L" level voltage input terminal of
OSC2 video signal

PD Clock pulse adjustment terminal RHH "H" level voltage input terminal of

video signal

C-S Synchronizing pulse input terminal PS1 Mode control signal

HDB Horizontal synchronizing signal input VSS1 Power supply voltage input terminal

terminal

VDD1 VDD voltage input terminal

— 3 —