Nortel Networks Circuit Card - Manual (Page 556)

Page 556 of 906 NT8D09 Analog Message Waiting Line card
553-3001-211 Standard 3.00 August 2005
Table 179 provides a technical summary of the analog message waiting line
card.
Table 179
NT8D09 Analog Message Waiting Line card technical summary
Impedance 600 ohms
Loop limit (excluding set) 1000 ohms at nominal -48 V (excluding set)
Leakage resistance 30,000 ohms
Ring trip During silent or ringing intervals
Ringing voltage 86 V AC
Signaling Loop start
Supervision Normal battery conditions are continuously applied (approxi-
mately -44.5 V on ring and
-2.5 V on tip at nominal -48 V battery)
Power input from backplane -48 (can be as low as -42 for DC-powered systems), +15,
-15, +8.5 V and ringing voltage; also -150 V on analog mes-
sage waiting line card.
Insertion loss 6 dB + 1 dB at 1020 Hz
3.5 dB loss for analog to PCM,
2.5 dB loss for PCM to analog