Instruction manual

Hardware Overview
22 025-9416
Jumper Function Settings Default
JP8
Factory test only
IN
OUT
OUT
JP9
Factory test only
IN
OUT
OUT
JP10
Factory test only (µProcessor U33 XIRQ)
IN
OUT
OUT
DUAL TRUNK INTERFACE BOARD
The dual trunk interface board (Part No. 702-9361) connects two telephone lines to the paging
terminal. Telephone lines are brought to the dual trunk interface board (item #5, Figure 2)
through the peripheral board from the male 50-pin connector on the rear of the unit (item #15,
Figure 3). The lines associated with trunks A and B are brought to the dual trunk installed in the
rightmost slot, J3/J5. The lines associated with trunks C and D are brought to the dual trunk
installed in the leftmost slot, J2/J4.
Line Type Matrix Card
The dual trunk interface board can service four telephone line types. A four-position dual trunk
matrix card (Part No. 702-9122) determines the type of interface for each line of the trunk card.
The two trunks need not be set to the same line type. Each position of the matrix card enables the
Model 640 to interface to one or more telephone line types as indicated below:
DID
Loop start trunks:
C.O. selector level
Local
PABX
E-E
End-to-End loop start trunks (also called “POTS”- plain old telephone service)
RS-232 port for TAP input
E&M
DID trunk, reverse battery supervision
PABX tie trunk with 2-wire audio signaling
GND ST
Ground start End-to-End trunks
Note: The matrix cards and line types are factory set for the custom application described
to Zetron technical staff when ordering. In general, the matrix cards should be left in
the factory settings unless the telephone line configuration changes.
The matrix card in socket J3 of the dual trunk interface board configures trunk A and the matrix
card in J4 configures trunk B. The selected line type is indicated by the matrix card marking that
is on the bottom side of the socket (when trunk card is installed on peripheral board) labeled “1”
on the dual trunk board as shown in Figure 6.