Hitachi CG2026S, Service Manual

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DO NOT CHANGE ANY MODULE UNLESS THE SET IS SWITCHED OFF
The mains supply part of the switch mode power supply’s transformer is live.
Use an isolating transformer.
The receiver complies with the safety requirements.
SAFETY PRECAUTIONS:
The service of this TV set must be carried out by qualified persons only. Components marked with the warning symbol
on the circuit diagram are critical for safety and must only be replaced with an identical component.
- Power resistor and fused resistors must be mounted in an identical manner to the original component.
- When servicing this TV, check that the EHT does not exceed 26kV.
TV set switched off:
Make short-circuit between HV-CRT clip and CRT ground layer.
Short C809 before changing IC800 and IC801 or other components in primary side of the SMPS part.
Measurements:
Voltage readings and oscilloscope traces are measured under the following conditions:
Antenna signal’s level is 60dB at the color bar pattern from the TV pattern generator. (100% white, 75% color saturation)
Brightness, contrast, and color are adjusted for normal picture performance.
Mains supply, 220VAC, 50Hz.
PERI-TV SOCKET
SCART 1 (SC050) SCART 2 (SC051)
1 Audio right output 0.5Vrms / 1K 1 Audio right output 0.5Vrms / 1K
2 Audio right input 0.5Vrms / 10K 2 Audio right input 0.5Vrms / 10K
3 Audio left output 0.5Vrms / 1K 3 Audio left output 0.5Vrms / 1K
4 Ground AF 4 Ground AF
5 Ground Blue 5 Ground Blue
6 Audio left input 0.5Vrms / 10K 6 Audio left input 0.5Vrms / 10K
7 Blue input 0.7Vpp / 75ohm 7 Blue input 0.7Vpp / 75ohm
8 AV switching input 0-12VDC /10K 8 AV switching input 0-12VDC /10K
9 Ground Green 9 Ground Green
10 -10 -
11 Green input 0.7Vpp / 75ohm 11 -
12 -12 -
13 Ground Red 13 Ground Red
14 Ground Blanking 14 Ground Blanking
15 Red input 0.7Vpp / 75ohm 15 -
16 Blanking input 0-0.4VDC, 1-3VDC / 75ohm 16 -
17 Ground CVBS output 17 Ground CVBS output
18 Ground CVBS input 18 Ground CVBS input
19 CVBS output 1Vpp / 75ohm 19 CVBS output 1Vpp / 75ohm
20 CVBS input 1Vpp / 75ohm 20 CVBS input 1Vpp / 75ohm
21 Ground 21 Ground
1. INTRODUCTION
This
is a 90° chassis capable of driving 20”/21” tubes at the appropriate currents. The chassis is capable of operating
in PAL, SECAM and NTSC standards. The sound system is capable of giving 5 watts RMS output into a load of 8 ohms.
One page, 7 page SIMPLETEXT, TOPTEXT, FASTTEXT and US Closed Caption is also provided. The chassis is equipped
with a double-deck 42 pin Scart connector.