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2-WIRE IDSL LINE DRIVER RACK CARDS
2. Perform a V.52 BER test as described in
Section 5.2.3
. If the BER test
equipment indicates a fault and the local line loopback test was successful for
both Cards, you may have a problem with the twisted-pair line between the
modems. You should then check the twisted-pair line for proper connections
and continuity.
5.2.3 V.52 (BER) T
EST
-P
ATTERN
G
ENERATOR
To use the V.52 BER tests in conjunction with the Remote Digital Loopback tests
(or with local line loopback tests), follow these instructions:
1. Locate the 511/511E toggle switch on the Card’s front panel and move it to
the left. This activates the V.52 BER test mode and transmits a 511 test pattern
into the loop. If any errors are present, the local modem’s red ER LED will
blink sporadically.
2. If the above test indicates no errors are present, move the V.52 toggle switch
to the right, activating the 511E test with errors present. If the test is working
properly, the local modem’s red ER LED will blink approximately once per
second. A successful 511E test will confirm that the link is in place and that
the Card’s built-in 511 generator and detector are working properly.
