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IDSL LINE DRIVER W/V.35 OR X.21
5.4 Using the V.52 (BER) Test-Pattern Generator
To use the V.52 BER tests in conjunction with the Remote Digital Loopback tests
(or with Local Line Loopback tests), do the following:
1. Locate the 511/511E toggle switch on the Line Driver’s front panel and set
the toggle to the down position. 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 continuously.
2. If the above test indicates that no errors are present, move the V.52 toggle
switch to the up position, activating the 511E test with errors present. If the
test is working properly, the local modem’s red ER LED will blink. A
successful 511E test will confirm that the link is in place, and that the Line
Driver’s built-in 511 generator and detector are working properly.
