Madrigal Imaging MP-9 - Manual (Page 65)

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.”
OPERATION
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