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CIRCUIT DESCRIPTION
Sync Circuit Block Diagram Explanation
I401 - Luminance Audio Selector IC
VOut1 PinP (Sub) Video to I005 Main/Sub Select IC and also to I001 microprocessor for Sub CCD.
V/YOut2 Main Video or S-Video (Y) to I005 Main/Sub Select IC and also to I001 microprocessor for
Main CCD.
VIn4 Component 1 Y in for CCD (480i only) and Auto Link.
VIn5 Component 2 Y in for CCD (480i only) and Auto Link.
Component Inputs (Y)
Component 1 (Y) to I015 Component 1 Sync Separator IC.
Component 2 (Y) to I016 Component 2 Sync Separator IC.
I015 - Component 1 Sync Separator IC
Vertical sync out goes to I001 microprocessor IC Comp 1 VFDet.
Horizontal sync out goes to I005 Main/Sub Select IC.
I016 - Component 2 Sync Separator IC
Vertical sync out goes to I001 microprocessor IC Comp 2 VFDet.
Horizontal sync out goes to I005 Main/Sub Select IC.
I005 - Main/Sub Select IC
Select control from I001 microprocessor SD Sel (Station Detect) Low = Main, High = Sub
Three separate sets of inputs/outputs, (only first two shown in graphic)
pin 3 Sub Video (In)
pin 5 Main Video (In)
pin 4 Sub/Main SD Det (Out)
pin 2 Comp 1 H sync (In)
pin 1 Comp 2 H sync (In)
pin 15 Comp 1/2 HFDet (Out)
pin 12 Sub AFC (In)
pin 13 Main AFC (In)
pin 14 Sub/Main AFC (Out)
I001 - Microprocessor IC
Sub video in on pin 30 for CCD.
Main video in on pin 28 for CCD.
Component 1 vertical frequency detect on pin 10, from I015.
Component 2 vertical frequency detect on pin 11, from I016.
Component 1/2 horizontal frequency detect on pin 22, from I005.
SD Select out on pin 50 to control I005 during Sub picture changes; example PinP CH up or down.
Main/Sub SD detect in on pin 24 from I005.
I406 - Main Component 1 / Component 2 Select IC
Selected Y output on pin 6.