Toshiba 57VW9UA, Service Manual

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GENERAL ADJUSTMENTS
SPECIFIC INFORMATIONS
4-3 PART DESCRIPTION
QT01 SAA5665HL/SAA5695HL(P2)
QT01 works as Sub Micro Computer. It contains CPU(80C51), Data Capture and Display Hardware for Teletext. The block
Diagram of SAA5665HL/SAA5695HL(Painter II, P2) is shown in Fig. 4-3-1.
SAA5695HL will support the progressive scan mode (under development).
Fig. 4-3-1 SAA5665HL/SAA5695HL Block Diagram
Problem
No Teletext
Check Point
To check BUS CONT Error, using Self Check Menu of service mode.
To check +5V
To check 12MHz Clock
Table 4-4-1
Group Delay Compensation Filter
The Group Delay Compensation Filter Circuit is shown in Fig. 4-3-2, and improves the acquisition performance of the full
data service slicer for CVBS signals with group delay, but it is dependent on Tuner, IF performance and region. Use or Not
use this filter is set by the Sub data SYS (00h=Use this filter and CVBS0 is valid, 02h=Not use this filter and CVBS1 is valid).
Not use this filter and CVBS1 is valid at factory default setting (SYS=02h). According to signal condition, it is changed to
CVBS0 (SYS=00h) by the Sub data SYS. Sub data (SYS) is able to set for each channel position.
4-4 CIRCUIT CHECKPOINT
The major checkpoint of circuit is shown in Table 4-4-1.
Fig. 4-3-2