21
LDM-144LR
Table 3-1. LDM-144LR Switch and Jumper Settings.
PCB
Function
Details
Option
Factory
Name
Setting
J1
XMT CLK
Selects the transmit timing
RCV
signal from either internal
INT
INT
clock, external clock, or
receive clock.
J2
SW, ENABLE When set to ON, enables
SWITCH: ON
ON
activation of Diagnostics
SWITCH: OFF
through the front-panel
pushbuttons.
J3
CARR
When set to ON, the transmit
CARR: ON
ON
carrier is permanently
CARR: CNTRL
activated.
J4
CD SENS
Controls Carrier detect
CD SENS: LOW
sensitivity level. LOW: for
CD SENS: HIGH HIGH
short ranges. HIGH: for
ranges up to the product
limitation.
J5
[DTE COMM.] When set to ENabled, the
ALB: EN
EN
ALB
Analog Loopback signal
ALB: DIS
from the DTE is enabled.
J6
[DTE COMM.] When set to ENabled, the
RLB: EN
EN
RLB
Remote Loopback signal
RLB: DIS
from the DTE is enabled.