Patton 3086, Руководство пользователя

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9 • Diagnostics Model 3086 G.SHDSL Integrated Access Device User Guide
126 BIT Error Rate (V.52) Diagnostics
Figure 11. Remote Digital Loop
To perform an RDL test, follow these steps:
1. Activate the RDL by moving the front panel toggle switch DOWN to remote.
2. Perform a bit error test (BERT) using the internal V.52 generator (as described in Section X), or using a
seperate BER Tester. If the BER test indicates a fault, and the Local Line Loopback test was successful for
both Model 3086s, 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.
BIT Error Rate (V.52) Diagnostics
The Model 3086 offers a V.52 Bit Error Rate (BER) 511 test pattern. This test pattern may be invoked along
with the LAL and RDL tests to evaluate the unit(s) and the communication links. When a 511 test is invoked,
the 3086 generates a pseudo-random pattern of 511 bits using a mathematical polynomial. The receiving
Model 3086 then decodes the received bits using the same polynomial.
If the received bits match the agreed upon pseudo-random pattern, then the 3086(s) and the communication
link(s) are functioning properly. 511 Initiates a built-in 511 bit pseudo-random pattern generator and detector.
511 with Errors Initiates a built-in 511 bit pseudo-random pattern generator and detector. The test pattern
generator also injects intentional errors approximately once per second, causing the Error LED to blink.
To perform a V.52 BER test, follow these steps:
1. Locate the toggle switch group on the right side on the front panel and place it in the middle where it is
marked “Normal”. This activates the V.52 transmission and reception of the selected test pattern. If there
are errors in the received pattern, the error LED will blink accordingly.
2. If the above test indicates no errors are present, move the toggle switch UP to 511/E, activating the BER
test with intentional errors. If the test light is working properly, the local modem’s red error LED will blink
approximately once per second.
Note The above V.52 BER tests can be used independently of the Remote
Digital Loopback tests.