Nortel Circuit Card Installation Manual page 122

Page 122 of 906
Table 34
NT8D14 vintages BA/BB trunk types—termination impedance and balance network
(Part 2 of 2)
Trunk types
2-way tie (OAID)
DID (loop < 600
ohms)
DID (loop Š 600
ohms)
RAN: continuous
operation mode
Paging
Note 1: The terminating impedance of each trunk unit is software selectable in LD 14 and
should match the nominal impedance of the connecting equipment.
Note 2: The balance network of each trunk unit is software selectable between resistive 600 or
900 ohms or 3COM and is jumper selectable between 3COM1 and 3COM2.
553-3001-211 Standard 3.00
Option settings
Terminating
impedance
(Note 1)
(zero–3000 ft)
600 or 900
ohms
600 or 900
ohms
600 or 900
ohms
600 or 900 600 or 900 ohms
ohms
600 ohms
August 2005
Balance network for loop lengths (Note 2)
Zero–915 m
(3000–5000 ft)
600 ohms
600 ohms
600 ohms
600 ohms
915–1524 m
3COM1
3COM1
N/A
N/A
N/A
> 1524 m
(> 5000 ft)
3COM2
3COM2
3COM2
N/A
N/A