ADC ETU-751C - Manual (Page 61)

700-701-100-02 Viewing Status
UTU-701 and ETU-751 List 1 August 9, 2002 51
Monitor HDSL Span 1 Screen
The HDSL Span 1 screen ( Figure 33 ) displays the circuit performance and 24-hour error counts at the HDSL span
1 interface. A span is defined as the link between two HDSL units (that is, from an LTU to an NTU) which, in this
case, is comprised of a single loop (that is, one twisted-copper pair). The values under the LTU-1 column represent
HDSL Span 1 as measured by the LTU. The values under the NTU-1 column represent HDSL Span 1 as measured
by the NTU.
At the Monitor menu ( Figure 30 ), type to select the Monitor HDSL Span 1 screen ( Figure 33 ). The fields
displayed in the Monitor HDSL Span 1 screen are described in Table 26 .
Figure 33. Monitor HDSL Span 1 Screen
Table 26. Fields in Monitor HDSL Span 1 Screen
Field Description
Current Margin (dB) (MAR) Indicates the excess signal-to-noise ratio relative to a 10 -7 bit error rate. The normal range of
a typical margin is from 6 to 22 dB, with a value of 6 dB corresponding to a predicted BER of 10 -10 .
Low Margin (dB) Indicates the lowest margin since startup or the last 24-hour history clear.
High Margin (dB) Indicates the highest margin since startup or the last 24-hour history clear.
Pulse Attenuation (dB) Indicates the attenuation of the 2B1Q pulse from the distant end. This value is related to the cable
pair’s loss at 292 KHz. The normal range of pulse attenuation is from 1 to 41 dB.
Errored Seconds (ES) The number of one-second intervals in which at least one HDSL CRC-6 error or loss of Sync Word
(LOSW) was detected on the HDSL span during the last 24 hours.
Unavailable Seconds (UAS) The number of seconds that the HDSL span was down during the last 24 hours.
HDSL Tip/Ring Reversal Indicates whether the two conductors of the HDSL span are correctly connected or have been
interchanged. The system automatically compensates for an interchange of wire leads.
Clear 24-Hour History The date and time that the 24-hour histories were last cleared are displayed here. Enable this
function by pressing
or to clear all 24-hour history counters (including HDSL). This
action must be confirmed by pressing .
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L ENTER
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