Grass Valley MRC v.1.2 - Manual (Page 159)

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Miranda Router Configurator
User’s Guide
• 1080p/23.97 Tri-Level Reference (no software configuration)
All SD formats will switch, but not at the correct time.
There are no SD formats that frame-align with a 23.97Hz frame reference, so it is impossible
to guarantee an SD signal will switch at the correct point in time.
HD 1080p/23.97 will switch correctly.
All other HD standards will switch, but not at the correct time.
Redundant and Dual Video References
Each router has two video reference connectors. The same reference can be used at both
connectors or a different reference can be applied at each connector. When you are using the
same (or “redundant”) reference, if one reference fails, the control card automatically fails over
to the redundant reference.
You can select “redundant” or “dual” reference, globally, in the ‘Output Attributes’ page. (See
Output Attributes Page on page 50.)
Switching “Rules”
There are presently 5 aspects involved in what are called “switching rules.”
• Embedded group control (and “null” audio).
• Pass-through audio.
• Obsolete ‘AFV’ partition.
• Input attribute — force embedder on.
• Tally — effective status versus actual status.
Null Audio
By the creation and use of “null” audio sources, operators can control whether embedded audio
channels are null. Individually, null channels carry silence. When all 4 channels in an audio group
are null, the output embedder does not emit the group in the output.
See Embedded Group Control on page 151 for more information.
Pass-Through Audio
By the creation and use of a “pass-through” source, operators can route the embedded audio
from a standard video input to a hybrid (disembedder/embedder) output directly and with little
effort.
 This capability has existed, but with limitations. “Pass-through” eliminates the limitations.
See Pass-Through Sources on page 152 for more information.
AFV Partition
The routers’ switching rules accommodate ‘AFV’ partitions, but AFV partitions are not supported
by recent releases of MRC.
 If your router has an AFV partition and you want to continue to use it, do not delete it. You
cannot recreate it in the newer versions of MRC.