Switch S4 — Alternating and Contiguous Channels
The D-SERV DSU/CSU can be configured to activate channels
sequentially (contiguous) or configured to activate every other channel
(alternating). For example, if four channels have been activated and
the starting channel is channel 16, contiguous configuration will
activate channels 16, 17, 18, and 19. Alternating configuration will
activate channels 16, 18, 20, and 22.
Alternating channels is useful to preserve T1 pulse density if large
amounts of zeros are to be transmitted as data.
Switch S4-4 selects the alternating or contiguous channel option.
NOTE:
It is not allowed to activate more channels than can be
accommodated between the starting channel and the
24th channel. For example, in contiguous mode, if ten
channels have been activated and channel 16 has
been chosen as the starting channel the D-SERV
DSU/CSU will not function properly. In alternating
mode, if six channels have been activated and channel
16 has been chosen as the starting channel the
D-SERV DSU/CSU will alert the user of a configuration
conflict.
In the event of a conflict the D-SERV DSU/CSU will
flash the front panel POWER, RED ALARM, and DATA
LEDs red. The last valid starting channel selected by
the user is used until the configuration error is
corrected by the operator.
Switch S4 — Alternating and Contiguous Channel Options
Function
4
Contiguous Channels
Down
Alternating Channels
Up
Operator's Manual
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