Belden Grass Valley NV8900, Руководство пользователя

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8
NV8900
MADI to Analog Audio Interface
This is a front view of the MADI-to-analog-audio interface:
This is a rear view of the MADI-analog-audio interface:
Function
The MADI-to-AA interface accepts one or two MADI input streams. If it receives two MADI
signals, they should be identical. Only one of the MADI streams is active. The other if it is
present, is stand-by. The stand-by input becomes active if the active input fails.
 A failure occurs when the active input has 1 or more bit errors per second for 3 seconds
or more and the stand-by input has no bit errors.
The unit extracts 64 audio channels From the active MADI stream.
The 64 outputs are paired internally and are represented by 32 LEDs at the front of the
panel, one for each pair. Each of these LEDs acts as a primitive level meter for the pair,
according to the following scale:
LED state Audio Level Range
Off < –50 dBfs
Green –50 to -4 dBfs
Red > –4 dBfs to 0 dBfs
The unit accepts video reference. It derives its internal clocks from the video reference. It
can free-run, but it is advisable to use an external reference, especially when used with an
NV8500 hybrid router.
Other LEDs
Each MADI input is represented by an LED at the front of the unit. The color of the LED
represents the state of the MADI input:
• Green — the MADI input is good and active.
• Amber (or orange) — the MADI input is good and stand-by (inactive).
• Red — the MADI input is bad.
Alarm LED
Ref. LED
Rotary Switch
Channel LEDs
Power Supply LEDs
MAD I LEDs
Video Reference
(Loop-Through)
Ethernet
Serial
Analog Audio Outputs (DB25)
Fan
MADI Output (2)
DIP Switches
Power (2)