Casio JY-70B Troubleshooting guide

R
JY-70B (NTSC M / M)
JY-70C (PAL B / G,H)
JY-70I (PAL B / G)
JY-70N (PAL B / G,H)
(KX-516)
(without price)
JUL. 1998
INDEX

CONTENTS
Page
SPECIFICATIONS.....................................................................................1
BLOCK DIAGRAM.................................................................................... 2
PRINTED CIRCUIT BOARDS...................................................................3
PARTS LIST..............................................................................................7
EXPLODED VIEW...................................................................................11
SCHEMATIC DIAGRAMS.......................................................................12
WAVEFORMS.........................................................................................16

— 1 —
Item Specification
1. Power voltage DC 6.0 V
JY-70B Approx. 3.6 W
2. Power consumption JY-70C/N/I Approx. 3.3 W
JY-70B Approx. 600 mA
3. Current consumption JY-70C/N/I Approx. 550 mA
JY-70B Approx. 3.5 hours
4. Battery life (with alkaline batteries) JY-70C/N/I Approx. 4.0 hours
Batteries : 4 ×LR6 (D) size batteries
5. Power supply Car adaptor : CA-K65
AC adaptor : AD-K64
Earphone jack : 3.5 ø mini
External power jack : 6.0 V DC IN
6. Connection terminal External antenna jack : 3.5 ø mini
(only JY-70C)
Audio / Video jack : 3.5 ø mini
7. Screen size 2.3 inches
8. Number of picture elements 39,600 (360 ×110) dots
9. Dimension 126 mm (W) ×39 mm (D) ×78 mm (H)
10. Weight Approx. 220 g without batteries
SPECIFICATIONS
Model Color System TV System Channel
JY-70B NTSC M/M US VHF: 2 ~ 13 ch UHF: 14 ~ 69 ch
JY-70C/N PAL B/G,H CCIR VHF: 2 ~ 12 ch UHF: 21 ~ 69 ch
JY-70I PAL B/G ITALY VHF: A ~ H2 ch UHF: 21 ~ 69 ch

— 2 —
Antenna
1 TU200 2 Q200 3 IC200
7
Tuning
Voltage
Generator
VR600
Volume
Control
4 IC600 Speaker
IC300
IC700
Common
Driver LCD
Segment
Driver
Chroma
Circuit
Osc.
Display
Control
A-D Converter
Auto-Tuning
Control
5
6
8 Q800 ~ Q803, Q805, Q806
VR800 Display
Voltage
Generator
Brightness
Control
VCC2 (3.95 ±0.02 V)
VCC7 (34.2 ~ 41.8 V)
VEE1 (– 6.03 ~ – 7.37 V)
IC500
Power
Supply
Audio
Amp.
IF Amp.Tuner
Video
Sound Det.
FM
AFT Circuit
AGC Circuit
1— Color Tuner: TU200 TEAA1(JY-70B) / TEPE5-01(JY-70C/N/I)
Selects a desired radio wave and changes it to the video IF signal.
2— Video IF Amp.: Q200 2SC3082
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
EliminatesthecarrierwaveinthevideoIFsignal,andpicksupthevideosignalandthesoundIFsignal.
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 M52042FP
Generates the tricolor (red, green, and blue) from the video signal.
6— Osc./A-D Converter/Display Control/ Auto-Tuning Control : IC700 ML9661GA-6006
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 BA10358F
Generates the tuning voltage with the tuning pulse (TU) output from 6.
8— Display Voltage Generator: Q800 ~ Q803 Q805 Q806 2SD1819A, 2SB1218A, 2SD1149S
Generates the display voltages V0 ~ V4 with VEE1 and VCC7 outputs from the power supply.
BLOCK DIAGRAM

— 3 —
PRINTED CIRCUIT BOARDS
AD-PCB(JY-70B/C/N/I)
Top View
Bottom View

— 4 —
L-PCB(JY-70B)
Top View
Bottom View

— 5 —
L-PCB(JY-70C/N/I)
Top View
Bottom View

— 6 —
BL-PCB(JY-70B/C/N/I)
Top View
Bottom View

PARTS LIST JY-70B: NTSC (USA,Others)
JY-70C: PAL (Others)
JY-70I: PAL (Itary)
AD
PCB
ASS'Y
JY-70N: PAL (Europe,Germany)
Item Code No. Parts Name Specification Applicable Q R
Connector
3502 2214 CONNECTOR 52435-2291 JY-70 common 1 X
3502 2425 CONNECTOR 52271-1490 JY-70 common 1 X
3502 2426 CONNECTOR 52288-0211 JY-70 common 1 X
ICs
2012 6038 LSI ML9661GA-6006 JY-70 common 1 C
2114 2464 IC / LINEAR NJM2070M-T1 JY-70 common 1 C
2114 3311 IC / LINEAR M52045FP-T1 JY-70C/I/N common 1 C
2114 3458 IC S-81230SG-QB-T1 JY-70 common 1 C
2114 5853 IC TK11239BMCL JY-70B common 1 C
2116 0119 IC BA10358F-T1 JY-70 common 1 C
Jacks
3501 3773 JACK HSJ6063-01-410 JY-70 common 1 C
3501 5439 JACK HSJ1456-01-210 JY-70 common 1 C
Transistors
2251 0189 TRANSISTOR / CHIP 2SB1218A-R(TX) JY-70 common 2 B
2253 0133 TRANSISTOR / CHIP 2SD1819A-R(TX) JY-70 common 2 B
2253 0476 TRANSISTOR / CHIP 2SD1149-S(TX) JY-70 common 1 B
Switch
3412 1848 SWITCH / TACT SKQGAA JY-70 common 1 C
Variable Resistors
2765 0616 VOLUME RK09H11T-10KB JY-70 common 1 C
2765 0623 VOLUME RK09H11T-20KB JY-70 common 1 C
Oscillator
2590 2717 OSCILLATOR HD-49-4.43M JY-70C/I/N common 1 C
2590 2731 OSCILLATOR HD-49-3.58M JY-70B common 1 C
Notes : Q - Quantity used per unit
R - Rank — 7 —

LINEAR PCB
Item Code No. Parts Name Specification Applicable Q R
Diodes
2390 1183 DIODE / CHIP MA143A-(TX) JY-70B common 1 C
2390 1190 DIODE ERA15-01Y JY-70 common 1 C
2390 1470 DIODE / CHIP MA142WK-(TX) JY-70 common 1 C
7101 1194 DIODE / CHIP MA111(TX) JY-70B common 3 C
7101 1194 DIODE / CHIP MA111(TX) JY-70C/I/N common 2 C
Fuse
2797 5598 FUSE / CHIP PI-R429.750 JY-70 common 1 B
ICs
2114 1827 IC / LINEAR M51348FP-T1 JY-70 common 1 C
2114 3150 IC MB3776APNF-EF JY-70 common 1 C
2114 5853 IC TK112939BMCL JY-70B common 1 C
Jacks
3501 5439 JACK HSJ1456-01-210 JY-70 common 1 C
3501 8281 JACK HEC0811-010010 JY-70 common 1 C
Transistors
2251 0189 TRANSISTOR / CHIP 2SB1218A-R(TX) JY-70B common 2 B
2252 1050 TRANSISTOR / CHIP 2SC3082K-T146Q JY-70 common 1 B
2253 0133 TRANSISTOR / CHIP 2SD1819A-R(TX) JY-70B common 4 B
2253 0133 TRANSISTOR / CHIP 2SD1819A-R(TX) JY-70C/I/N common 1 B
2253 0308 TRANSISTOR / CHIP 2SD1119-R(TX) JY-70 common 1 B
Switch
3412 0938 SWITCH / SLIDE ESD11V231 JY-70 common 1 C
Converter
3065 0715 CONVERTER / DC-DC LC128-16 JY-70B common 1 B
3065 0672 CONVERTER / DC-DC LC12U-40 JY-70C/I/N common 1 B
Tuner
1014 9890 TUNER TEAA1-001A JY-70B common 1 C
1013 5315 TUNER TEPE5-01 JY-70C/I/N common 1 C
BL PCB ASS'Y
Item Code No. Parts Name Specification Applicable Q R
Transistors
2253 0287 TRANSISTOR 2SD965-R JY-70 common 1 B
Transformer
3012 1588 INVERTER TRANS C-8123 JY-70 common 1 B
Notes : Q - Quantity used per unit
R - Rank — 8 —