B&B Electronics 850-14200--95 - Manual User Manual

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Line Encoding

This option allows the user to set the transmit/receive encoding for HDB3, B8ZS
or AMI (default).

NOTE

There are currently no applications that use any other settings than AMI encoding
and NRZ disabled (Passive mode). Changing the encoding setting to anything other
than AMI can result in data corruption.

Transmit LIU Waveshape (Line Build-out)

The copper line driver for T1 applications can be adjusted to provide standard
pre-distortion (LBO) of the transmitted signal for DSX1 connections. The
transmitted signal level can also be reduced (-7.5dB to -22.5dB) when connecting
directly to a CSU that has limited input range.
For E1 circuits, the transmitter can be configured for either 75 ohm or 120 ohm
drive with normal or high (21db) return loss.

NOTE

The receive termination resistance should match this setting.

Receive LIU Termination (Line Termination)

This option allows the user to set the receive termination. This is used to properly
terminate cables in order to prevent signal reflections which can cause signal
degradation.

Transmit Data Source

This option allows the user to set the module to send normal data (default) or to
send specific test-patterns of data to determine problems along the cable as a
diagnostic tool. The user can set the module to send a PRBS (2

-1 for E1 and

-1 for T1), an alternating ones and zeros, or an unframed all ones code,

depending on the diagnostic requirements.

Jitter Attenuator Select

This option allows the user to select Jitter Attenuation on the UTP transmit or
receive side. This decreases jitter in the data stream which increases data
reliability.

NOTE

The jitter attenuator must always be enabled on the transmit side of the copper line.