22
HIGH-SPEED 2-WIRE SHORT-RANGE DSL LINE DRIVER RACK CARD
DTE Shield (M/34 Pin A) and FRGND (JB3)
In the connected position, this strap links M/34 pin A and frame ground. In the
open position, pin A is disconnected from frame ground.
Table 3-12. DTE shield and FRGND.
JB3
Position 1 & 2 = DTE Shield (Pin A) and FRGND connected
Position 2 & 3 = DTE Shield (Pin A) and FRGND not connected
FRGND and SGND (JB4)
In the connected position, this strap links signal ground and frame ground
through a 100-ohm resistor. In the open position, signal ground is disconnected
from frame ground.
Table 3-13. FRGND and SGND.
JB4
Position 1 & 2 = FRGND and SGND connected
Position 2 & 3 = FRGND and SGND not connected
3.3.3 DB15 (X.21) R
EAR
C
ARD
S
TRAP
S
ETTINGS
Figure 3-8 shows strap locations for the DB15 rear cards. These straps determine
various grounding characteristics for the terminal interface and twisted-pair lines.
JB3 and JB4 are user-configurable.