Mitsubishi V19-V21, Техническое руководство

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7-2
NTSC Signal Selection
Figure 7-1 illustrates the NTSC Signal Selection cir-
cuitry. The circuitry is basically the same as in the V17
chassis. However, some pin numbers and nomencla-
ture are different, due mainly to the addition of another
NTSC External Input.
IC2L00 selects main and sub picture NTSC signal from
the External 1, 3, 4 and 5 Inputs. External 5 inputs are
the front panel inputs.
IC2K00 selects main and sub picture signals from
IC2L00, or from the External 2 input, Main Tuner or
Sub Tuner. The selected main picture signals are di-
rected to 3DYC Comb Filter circuitry, and sub picture
video is directed to the Sub Decoder.
The COMP-1, COMP-2, DTV and VGA inputs are
directed to YCbCr Select circuitry on the PCB-SIG-
NAL. Since a Set Top Box is not required to receive
HD broadcasts, the DTV inputs are mainly used for
connection to a Digital Broadcast Satellite (DBS).