Avaya Nortel Communication Server 1000 Reference page 139

loss, assuming direct current feed from the PBX with constant voltage at the feeding bridge.
However, this compensation is not available when:
• the termination is a non-compensating telephone
• the OPS port is served by a line card using a constant-current feeding bridge
• the OPS termination is to telephones behind a local switch providing local current feed,
such as a fax machine or a key telephone system
OPS line terminations with loudness characteristics designed for other applications can also
impact transmission performance. For example, wireless portables loudness characteristics
are selected for connections to switching systems for wireless communication systems; if used
in an OPS arrangement without consideration for these characteristics, the result could be a
significant deviation from optimum loudness performance.
Circuit Card Reference
Application
July 2011 139