About the Sync Routing System
The Sync Routing System allows various sync and video combinations to be made to the Input 01 or 02 on the Video Input Module. You can connect Video signals with Separate sync (R-G-B-H/C-V), Composite sync (R-G-B-H/C) or Sync-On-Green (R-Gs-B).
As well, the routing system allows Composite Video signals to be connected through the Green BNC and routed to the Marquee Decoder as long as the Recall (or Input) memory assigned to the Composite Video source is set for routing as Composite Video. From the PIC menu, select “Signal Routing” (item 9), then select “As Composite” (item 2) in order to force the routing to the Marquee Decoder.
Similarly, the system allows you to connect S-Video (Y/C) signals to the Red (for Y) and Blue (for C) BNCs, where they are routed to the Marquee Decoder if the Recall (or Input) memory assigned to the S-Video source is set for routing as S-Video. From the PIC menu, select “Signal Routing” (item 9). Then select “As S-Video” (item 3) in order to force the routing to the Marquee Decoder.
The IC at the U41 location on the Video Input Module (VIM) determines the priority and routing of incoming and outgoing sync. The VIM also includes Sync-On-Green circuitry which strips sync information from signals connected to the Green BNC. The IC then outputs the appropriate sync from the VIM to the Deflection Processor Board (DPB), which locks the operating frequency of the projector to the sync it receives. Set “Auto Clamp” in one of two ways, as described below.
1)If the routing is set to either “As Composite” or “As S-Video”, setting “Auto Clamp” to “On” routes the sync to the DPB from the Decoder. This setting is required for S-Video to operate properly. It also allows Composite Video to operate. Setting “Auto Clamp” to “Off ” routes the sync to the DPB from the Sync-On-Green circuitry. This is valid for Composite Video operation only, since the Composite Video is connected to the Green BNC. (NOTE: If using a Composite Video source with ASR, “Auto Clamp” must be set to "off. This is required for source change detection which is an integral part of ASR operation. When “Auto Clamp” is set to “Off ”, you must set the “Horiz Position” slidebar to approximately 25. This is due to a phase delay between the sync from the decoder and the sync from the Sync-On-Green circuitry.)
2)In all other cases – that is, when NOT routing the signal to the decoder – setting “Auto Clamp” to “On” results in back-porch clamping. If Sync-Tip clamping is required, set “Auto Clamp” to “Off.”
