P
AGE
10
44023-1297 <90-00058>
APPLICATION INFORMATION
T
he 44023s primary application is to interface a four-wire
trunk or two-wire outside line to Dantels 440 Communica-
tion Management System. The module also interfaces control
functions between the outside facilities and the 440 system.
The 44023 can be used in custom package applications of the
440 System. Modules necessary to provide the signaling and
control interface for the 44023 include:
♦
44020 DTMF Decoder
♦
49020 Tone Supply Subassembly
♦
49018 Address Decoder (or 44021/49021 Address Decoder
with subassemblies)
Fig. 3 shows an E and M trunk application diagram. Fig. 4
shows a two-wire line application diagram.
440 System Functions
For an outgoing call, the 44023:
♦
Seizes the trunk or line when a station or group call input is
applied from a decoder,
♦
Sends an off-hook tone to the caller,
♦
Passes dial tone from the trunk to the caller, and
♦
Passes signaling tones from the caller to the trunk.
The call is terminated when the station call or group call input
is removed by the decoding of an on-hook tone from the caller.
For an incoming call from the trunk or line, the 44023 answers
the ring by seizing the line. It sends an:
♦
Off-hook tone to the 440 system, and
♦
An alert tone to the trunk.
If the 44023 does not receive an off-hook tone from the 440
system within 10 to 80 seconds (adjustable), it will terminate the
call (Loop Control in). If the 440 system is busy when the incom-
ing call is placed, the 44023 will:
♦
Answer the call,
♦
Provide a seven second busy tone to the caller, and
♦
Terminate the call.
