X.21 LINK TESTING

1. CHECK THE X.21 LINK THROUGH NMS
2. IDENTIFY THE X.21 CHANNEL
3. LOOP BE MADE OF THE CONNNECTOR OF THE CABLE AT BACK PANEL OF THE HUB i.e. IN THE END OF THE CABLE COMING FROM MUX AT ONE END AND BER TESTING BE PERFORMED ON THE BER TESTER.
4. IF IT IS OK THEN SEE THE CABLING AND CONNECTOR
5. LOOP BE MADE OF THE CONCERNED CHANNEL IN THE SERVICE TERMINAL AVAILABLE AT RSCC AT ONE END AND BER TESTING BE PERFORMED ON THE BER TESTER .
6. IF IT IS OK .THEN A LOOP BE MADE IN THE

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