Grass Valley NV8500 Series v.3.5 - Manual (Page 66)

50
Inputs and Outputs
I/O Cards
forwards the signal to a connector. The monitor selector forwards the signal, via the mother-
board, to a monitor card. (See
Monitoring on page 89.)
The following diagram shows the flow of a signal through HD or 3Gig standard I/O cards.
Fig. 2-17: Block Diagram of HD or 3Gig I/O Signal Flow
Hybrid (3Gig)
Note: Most hybrid cards require coax connectors. They do not use fiber backplanes. The excep-
tion are the IP gateway cards which use SFP (fiber) backplanes.
With 3Gig hybrid I/O cards, the router can switch embedded audio channels independently.
Hybrid cards in this classification are the disembedder (input) card, the embedder (output) card,
and the disembedder/embedder (output) card. For NV8500 routers other than the NV8140, a
disembedder card has 8 disembedders, one for each video input. For the NV8140, a disem-
bedder card has 16 disembedders, one for each video input.
An embedder output card and a disembedder/embedder output card each have 16 embedders,
one for each output.
A disembedder on an input card extracts the embedded audio from its video stream. The audio
is then forwarded to the TDM audio “matrix” for routing.
Frame sync input card can be considered disembedder cards that have an additional RJ-45 port
for configuring frame sync functions.
IP gateway input cards can be considered disembedder cards that have an additional RJ-45 port
for configuring IP functions. IP gateway output cards can be considered embedder cards that
have an additional RJ-45 port for configuring IP functions. The input cards relay incoming video
streams to the 8 ports of the card. The output cards packetize the 8 video ports of the card into
video streams that are transmitted on the SFP connectors of the card.
Embedders on an output card re-integrate audio signals from up to 16 sources into the
outgoing video stream.
The disembedder/embedder output card has a disembedder and 16 audio multiplexers, in addi-
tion to the embedder, for each output. Router logic can select for each audio channel of each
output one of the following sources: (1) the equivalent audio channel from the video at the
output, (2) generated silence, or (3) audio from other sources, via the TDM audio matrix.
If a disembedder detects a Dolby E pair in its video stream, the disembedder instantly phase-
aligns the channel pair. Long-term phase alignment is provided for all other channels. If the
Note
Cable drivers are not present on fiber optic output cards
9
Monitor
Selector
9 video Cable
Equalizer
TDM
Matrix
to Monitor
Card
Cable
Driver
18
Monitor
Selector
18 video
Reclocker
to Monitor
Card
Crosspoint
Matrix