Model 458-SM-2-16 Transparent Switching Module
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To minimize input signal reflections and source noise, all unselected input signal lines are terminated with a 100-ohm
0.25 watt resistor, and all unselected channel output lines are source terminated with a 100-ohm 0.25 watt resistor.
2.3
Operation as a Demultiplexer
Model 458-SM-2-16 Transparent Switching Module may also be used as a demultiplexer. The paths between the input
and output connectors are bi-directional, which allow signals to flow in either direction without a change in the signal
characteristics. Therefore, two input signals may be connected to the RJ-45 rear connectors, and provide the selection of
up to sixteen outputs at the front 16 RJ-45 connector lines. The selection of the paths and the firmware control logic in the
demultiplexer configuration is identical to the control logic and selection when used as a multiplexer. The paths are:
Mode 1: The upper RJ-45 rear connector input signal may connect to any one of the front 16 RJ-45
differential lines when the lower-rear RJ-45 is not selected.
Mode 2: The lower RJ-45 rear connector input signal may connect to any one of the front 16 RJ-45
differential lines when the upper-rear RJ-45 is not selected.
Mode 3: The upper RJ-45 rear connector input signal may connect to any one of the front RJ-45 connectors 1
though 8 differential lines and the lower RJ-45 rear connector input signal may connect to any one of the front
RJ-45 connectors 9 through 16 differential lines.
