Patton electronics 2720/I Series User Manual page 12

3.1.2 Switch S1
The chart below shows the default configurations for Switch S1. A
description of all S1 options follows this table.
Switch S1-1: RDL Type
Switch S1-1 selects the type of Remote Digital Loopback that the
2720 will initiate when the RDL is initiated from this unit. The 2720 will
respond to both the V54 and the CSU loopback regardless of the set-
ting of S1-1
S1-1
On
Off
Switch S1-2: Reserved
Switch S1-3: Tx Clock Invert
Switch S1-3 allows the user to invert the transmit clock originating
in the 2720. When S1-2 is set for transmit clock, it may be necessary
to invert the transmit clock to allow for delays due to long cables.
S1-3
On
Off
Switches S1-4 and S1-5: Line Build Out
Use Switches S1-4 and S1-5 to set the Line Build Out (LBO). The
Line Build Out varies the pulse shape and attenuation of the signal
sent to the network. The amount of Line Build Out depends on
NetLink™ T1's distance to the last repeater. The telephone company
providing the service will advise on the amount of LBO necessary. In
most cases the default setting will suffice.
SW1-4
Off
On
Off
On
Switch S1-6 Through S1-8: Reserved
RDL Type
Initiate a V.54 RDL loop when selected
Initiate a CSU loopback when selected
Tx Clock Invert
Transmit clock is inverted
Transmit clock is normal
SW1-5 Function
Off (0dB)
Off -7.5dB
On -15.0dB
On -22.5dB
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