Nortel Networks 4455 Network Card User Manual


 
T1, E1, and Digital Voice ModulesPassport 4400 Hardware Installation Manual
5-12
Figure 5-12. DVEM Power Harness
Digital Voice Module
Digital Voice Module (DVM - NTAU60AA) is a daughterboards that fit into a
slot on top of the T1/E1 Voice Module or the Digital Voice Expansion Module. It
is often referred to as a single in-line memory module (SIMM). Along with
providing a second bank of flash memory, the Digital Voice Module has a Real
Time Clock (RTC) which maintains network time and date and is synchronized
with the integrated network.
Figure 5-13. Digital Voice Module
Each Digital Voice Module provides one digital voice channel that the T1/E1
Module supports. It compresses 64 Kb/s of pulse code modulation digitized
voice obtained from the DSX-1/L1 interface into low-speed channels, thereby
optimizing the use of the available bandwidths.
Up to six may be installed in a T1/E1 Voice Module
Up to 12 may be installed in Digital Voice Expansion Module
TBD
To Power
Sharing Board
Do Not Connect
Harness to a T1/E1
Voice Module
TVM/EVM
DVEM
Rear
Front View
TVM = T1 Voice Module
EVM = E1 Voice Module
DVEM = Digital Voice Expansion
To DVEM