18
V.35 SINGLE FIBER DRIVERS
a) Activate remote loopback by moving the front-panel toggle switch up to
“Remote.” The “test” LED should glow.
b)Perform a BERT (bit error rate) test on the system.
c) If the BERT test equipment indicates a fault, and the local loopback test
was successful for both V.35 Single Fiber Drivers, there may be a problem
with the fiber communication line connecting the modems. You should
test the fiber line for proper connections and continuity.
Figure 5-2. Local and remote loopback test modes.
5.4 Power-down
Turn off the V.35 Single Fiber Driver by simply unplugging the AC power
adapter from the wall. There is no power switch on the Driver.
TD
RD
TX
RX
RX
TX
RD
TD
Local Driver
in Loopback Mode
Remote Driver
in Normal Mode
TD
RD
TX
RX
RX
TX
RD
TD
Local Driver
in Normal Mode
Remote Driver
in Normal Mode
