ADTRAN DSU 5600 User Manual

61200.078L1-1 DSU 5600 User Manual 2 1Chapter 3. Test ModesFAR END TESTSRemote Digital Loopback (RDL)When the remote digital loopback (RDL) test is initiated at thelocal DSU 5600, it commands the remote DSU into loopback withthe industry standard V.54 loopback pattern. The loopback pointand the signal paths for the remote DSU are the same as theLoop Only test for a local DSU (Figure 3-4). This loopback test isperformed with data from the terminal or test equipment.To initiate the RDL test, perform the following steps:1. Press the Select switch five times to turn On the RDL testindicator.2. Press Test while the test indicator is On. The RDL LEDFlashes during initialization of the test and turns On solidonce the test is in progress.To terminate this test, press Test.RDL with Test Pattern (TP)When the RDL with TP test is initiated at the local DSU 5600, itcommands the remote DSU into loopback with the industrystandard V. 54 loopback pattern. The loopback point and thesignal paths for the remote DSU are the same as the Loop Onlytest for a local DSU (Figure 3-4). This loopback test is performedwith data from the internal test pattern generator and errordetector.To initiate the RDL with TP test, perform the following steps:1. Press Select six times to turn On both the RDL and PTRNtest indicators.2. Press Test while these test indicators are On. The RDL andPTRN LEDs Flash during initialization of the test and turnOn solid once the test is in progress.To terminate this test, press Test.