Line Shield & FRGND (JB2)
This jumper affects the line interface. In the connected (closed)
position, it links RJ-11 pins 1 & 6, or RJ-45 pins 2 & 7 to frame ground.
These pins can be used as connections for the twisted pair cable
shield. In the open (disconnected) position, pins 1 & 6 (or 2 & 7)
remain connected to each other, but are “lifted” from the frame ground.
JB2
Position 1&2 = Line Shield and FRGND Connected
Position 2&3 = Line Shield and FRGND Not Connected
DTE Shield & Frame Ground (JB3)
In the connected position, this jumper links DB-25 pin 1 (M/34 pin
A) & frame ground. In the open position, pin 1(pin A) is “lifted” from
frame ground.
JB3
Position 1&2 = DTE Shield (DB-25 Pin 1 or M/34 Pin A)
and FRGND Connected
Position 2&3 = DTE Shield (DB-25 Pin 1 or M/34 Pin A)
and FRGND Not Connected
Signal Ground & Frame Ground (JB4)
In the connected position, this jumper links DB-25 pin 7 or M/34 pin
B (Signal Ground) and frame ground. In the open position, pin 1 (or pin
B) is “lifted” from frame ground.
JB4
Position 1&2 = SGND (DB-25 pin 7 or M/34 pin B)
and FRGND Connected
Position 2&3 = SGND (DB-25 pin 7 or M/34 pin B)
and FRGND Not Connected
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3.2.1 REAR CARD JUMPER SETTINGS
Figure 6 (below) shows jumper locations for the four rear card
options. These jumpers determine various grounding characteristics for
the RS-232/V.35 and twisted pair lines.
Figure 7 (below) shows the orientation of the rear interface card
jumpers. The jumper can either be on pegs 1 & 2, or on pegs 2 & 3.
The table below provides an overview of interface jumper functions
for the rear interface cards. Following this overview is a detailed
description of each jumper’s function.
11
Figure 6. Rear card jumper locations
JB2
(peg 1 on left)
JB3
(peg 1 on top)
JB4
(peg 1 on left)
1
2
3
1
2
3
1
2
3
Figure 7. Orientation of interface card straps
REAR CARD STRAP SUMMARY
Strap
Function
Position 1&2
Position 2&3
JB2
Line Shield & FRGND
Connected
Open*
JB3
DTE Shield (Pin1) & FRGND
Connected
Open*
JB4
FRGND & SGND
Connected
Open*
