ETU-01(U) User Manual - CTC Union Technologies Co.,Ltd.

Chapter 4. Test & Diagnostics4.4 Local Analog Loop BackThis test is activated by depressing the "Loc ana loopbk" button. This test checksthe performance of the ETU01, the local data terminal and the connections betweenthem. It is performed separately at the local and the remote sites (see Figure 4.2):Loc ana loopbkDepressedCLKDATAXMTRE1DATATERMINALCLKDATARCVRXETU-01Figure 4.2 Local analog loop back4.5 Local Digital Loop BackThis test is activated by depressing the "Loc dig loopbk" button. The test consistsof looping the received data back to the remote ETU01. This test checks theperformance of the local ETU01, the remote ETU01 and the connections betweenthem (see Figure 4.3).Loc dig loopbkDepressedLocalDataTerminalXMTRRCVRE1ETU-01Figure 4.3 Local digital loop back26