Mitsubishi Electric WS-48513, Руководство по устранению неисправностей

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6-3
Figure 6-2 illustrates the Sub Sync Signal Path for
the Sub-Picture signals on the PCB-Terminal. It
functions the same as the Main Sync Signal Path
using different pin sets on the same ICs. The sub
sync signals are used by Doubler circuitry for POP/
PIP signal processing.
Figure 6-3 shows the sync signal functions per-
formed by the PCN-Signal. It serves to interface the
sync signals as follows:
• DVI and DM inputs to the PCB-Terminal
• Selected Main and Sub sync signals from the
Terminal to the Doubler PCBs.
• Sync from the doubler to the VCJ
The selected sync is directed to the Doubler circuitry.
If the selected source is 480i, the number of hori-
zontal lines are doubled. When the selected source
is 480p or 1080i, no line doubling is required. How-
ever, since all sync signals, 480i, 480p and 1080i
pass through the PCB-DOUBLER, the TV cannot
be operated with the PCB-DOUBLER unplugged.
IC2X10 and IC2X11 are flip-flops serving as schmitt
triggers. They effectively remove any spikes or noise
that may be riding on the sync, preventing false trig-
gering.