Section 363-712-131-01
February 24, 1998
Revision 01
Page 42
PairGain Engineering - Plant Series
PG-Flex FLL-712 List 3A
F. ABBREVIATIONS AND GLOSSARY
14. Abbreviations
CO
Central Office
COT
Central Office Terminal
LU
Line Unit
MLT
Mechanized Loop Testing
PBX
Private Branch Exchange
PCM
Pulse Code Modulation
PGTC
Pair Gain Test Controller
POTS
Plain Old Telephone Service
RMA
Return Material Authorization
RT
Remote Terminal
15. Glossary
Margins
Indicates the excess signal to noise ratio, at either the COT or RT, relative to a 10
-7
Bit Error Rate. cr is the current margin, mn is the minimum margin since last
cleared, mx is the maximum value since cleared, and N/A means Not Available.
The normal range of a typical margin is from 22 to 6 dB.
Pulse Attenuation
Indicates the attenuation of the 2B1Q pulse from the distant end. PG-Flex operates
with pulse attenuations in excess of 30 dB. This value is related to the cable pair’s
196-kHz loss. The pulse attenuation is a more direct indication of the loop
attenuation to the 2B1Q signal than the 196-kHz loss. The normal range of pulse
attenuation is from 1 to 32 dB.
PPM
Indicates the relative offset of the crystal oscillator in the RT
line unit
from the COT
line unit
’s crystal oscillator. Any value between -64 and +64 is adequate. Values
outside this range indicate out of tolerance components or excessive temperature
drift of critical components.
HDSL 24 Hour
ES
The number of 1-second intervals that contained at least one CRC error. This value
is a running total of errored seconds (ES) for the last 24 Hours.
HDSL 24 Hour
UAS
The number of seconds (unavailable seconds) the HDSL loop was out of
synchronization.
Summary of Contents for PG-Flex FLL-712
Page 46: ......