TC Communications TC8612, Руководство пользователя

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Chapter 2 Installation System Configuration
2-5 TC8612 Rev 1.1 User Manual
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INT CLK:
Internal Clock. This switch (SW3) is used to setup the internal
clock. "On" for internal T1/E1 timing mode. "Off " for Rx loop timing.
•
B8ZS / HDB3:
This switch (SW4) is used to setup the T1/E1 Line Code. "On"
for B8ZS (T1) / HDB3 (E1). "Off" for AMI (Both T1/E1).
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DIS ALM:
This switch (SW5) is used to disable alarm outputs.
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L1, L2, L3:
These switches (SW6, SW7, & SW8) are used to set the DSX-1
cross-connect distance (copper line build-out) for T1 applications or the
impedance for an E1 application.
For example, in a T1/E1 application, this is the length of twisted pair cable
connecting the TC8612 to the user's equipment, which may be a CSU or DSU. See
Table 2-1 and Table 2-2.
Table 2-1: Copper Line Length Setup Table
Table 2-2: E1 Termination Setup Table
T1 Settings
L1 L2 L3 Application Line Length
Up Up Up DSX-1 (0 to 133 feet) / 0 dB CSU
Down Up Up DSX-1 (133 to 266 feet)
Up Down Up DSX-1 (266 to 400 feet)
Down Down Up DSX-1 (400 to 533 feet)
Up Up Down DSX-1 (533 to 655 feet)
Down Up Down -7.5 dB CSU
Up Down Down -15 dB CSU
Down Down Down -22.5 dB CSU
E1 Settings
L1 L2 L3 Application Termination
Up Up Up 75 Ohm Normal
Down Up Up 120 Ohm Normal
Up Up Down 75 Ohm High Loss
Down Up Down 120 Ohm High Loss