Ericsson LBI-39076B system manual GTI Telephone Interface, Revision-A Main Board, F2&F3, Out

LBI-39076B INSTALLATION

6. GTI TELEPHONE INTERFACE

The 6th step to install the ELI option is to configure each GTI telephone interface to match the type of telephone circuit to be connected to it. The first Main boards, identified by the manufacturer’s number 702-9588A, are configured differently than the later Main boards, identified by the manufacturer’s number 702-9588D or E. The boards are referred to as revision-A Main boards and revision-D or E Main boards respectively.

NOTE

Revision A Main boards do not support Direct Inward Dial (DID) telephone lines. If you need to have a DID telephone line connected to a GTI unit, that GTI unit must contain a revision-D or later Main board.

Be careful of terms when talking or reading about the telephone circuit that the GTI unit is to interface. Terms such as send, receive, in, out, E-Lead, and M-Lead are sometimes defined differently by different people and from different points of reference. The terms used in this manual are defined as follows:

∙4-Wire Send - audio voice signals from GTI unit to telephone circuit.

∙4-Wire Rec - audio voice signals from telephone circuit to GTI unit.

∙M-Lead - telephone circuit supervision signal from GTI unit to telephone circuit.

∙E-Lead - telephone circuit supervision signal from telephone circuit to GTI unit.

Revision-A Main Board

The revision-A Main board uses 15 jumpers (JP1 through JP15) and two fuses (F2 and F3) to configure the telephone interface. Set the jumpers and fuses to match the type of circuit to be connected to it. Figure 18 shows the locations of these jumpers and fuses on the revision-A Main board, and Table 2 lists the jumper and fuse configurations for four common types of telephone circuits. Figure 19 through Figure 22 show simplified schematics of these four configurations.

Many other configurations of the GTI telephone interface are possible. Table 3 shows which jumpers and fuses to use to obtain each specific interface characteristic. Figure 23 shows a simplified schematic of the interface, including key components and the location of each jumper and fuse. If a jumper or fuse is not specifically required for a characteristic, remove it. Not all characteristics are compatible with each other. For example, the interface cannot be configured for a -48 V reference for the E-Lead and at the same time be configured for an external reference for the M-Lead.

						RJ-45
					Telephone Line
					Connector					JP4
		D			C		C		C	JP5
				M				M
	JP1	C	F	B	D	D	B	B	D	JP6
		B	E		A		A	A
		A			JP2		JP3
	B
	C	JP8			JP7
	A
	JP9
	B
	A
	JP11
	JP10
	JP12	JP13
		B
		A
JP14	JP15							F2		F3
B	B
A	A

Figure 18 - Jumper Locations (Rev A Main Board)

Table 2 - Configurations by Line Type (Rev A Main Board)

TELEPHONE		JUMPER POSITIONS FOR JP1 THROUGH JP15																FUSES
LINE TYPE	1	2	3	4	5	6		7	8		9	10	11	12	13	14	15	F2&F3
End-to-End Loop Start	-	B	B	-	-	-		-		A	B	-	-	-	A	A	A	OUT
End-to-End Ground Start	D+M	B	B	-	-	-		-		B	A	-	-	B	A	A	A	IN
4-Wire E&M, Microwave	E	A+C	A+C	IN	IN		C+M	-	-		-	IN	IN	A	-	B	B	OUT
4-Wire E&M, Type I	E	A+C	A+C	-	-		C+M	-	-		-	IN	IN	B	-	B	B	IN

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