GRASS VALLEY 7500NB, Instruction Manual

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2-18 7500 Series Instruction Manual
Section 2 — Installation
The 7500WB Global Serial Channel connection has the same requirements
as the 7500NB. See
Figure 2-15 .
Figure 2-15. WB Global Serial Channel Connectors
References
7500NB AES Reference
7500NB systems have dual AES reference inputs. Two AES sync reference
loop-thru inputs provide a 48 kHz AES formatted signal upon which the
router bases its re-synchronization to frame and block boundaries. This
signal is assumed to be present for the router to be called synchronous. Two
inputs are provided for redundancy. In the event of loss of one AES refer-
ence the router will default to the second reference if one is present, other-
wise, it will default to asynchronous operation.
In systems with mixed module types (async and sync input and output
modules) the reference signal is required for the synchronous modules to
function properly. In systems that contain only asynchronous input and
output modules the reference signal is not required.
Figure 2-16 shows the flow of the AES reference signal. All signals have to
be terminated at the end of the flow. Cables must be as short as possible and
each cable pair must be the same length. Input Signal 1 and Input Signal 2
is one cable pair. Output Signal 1 and Output Signal 2 is another cable pair.
7500WB 128X128
7000 Control Frame
Global Serial Channel
(node bus)
193-224 129-160 193-224 129-160 65-96 1-32 65-96 1-32
INPUTS INPUTS OUTPUTS OUTPUTS
IN
1 2 1 2
1 2 3 4
GSC
MC1
MC2
OUT
MONITOR VIDEO REF
DIGITAL VIDEO REF
1 2 +
_
75 Ohm Terminator
0723_00_8_r0