1. Principles of Voice & Data Lesson 4: Troubleshooting Bellevue Community College Bob Young, Instructor

2. Troubleshooting Terms Short A connection between two wires where no connection is intended

3. Troubleshooting Terms Open No connection, typically where there should be one

4. Troubleshooting Terms Terminator A line ending, typically a connector Example: RJ-45

5. Troubleshooting Terms Cross Def. 1: two wires are touching ("crossed") where they shouldn't be Def. 2: two wires are reversed in a connector (ex. - Pin 2 wired to Pin 3 and Pin 3 wired to Pin 2)

6. Troubleshooting Terms Roll Two wires of the same pair are reversed at opposite ends of the cable

7. Important Distinction Be sure you understand the difference between a "crossover cable" and a "rollover cable"

8. Troubleshooting Terms Polarity Associated with the positive and negative terminals of the source DC voltage

9. Troubleshooting Terms Split One wire of one pair is crossed with a wire from another pair

10. Troubleshooting Terms Line Imbalance Unequal voltages on the two wires in a pair. This results in distortion, loss, and noise.

11. Troubleshooting Terms Loopback Testing Testing from one end a line. A signal is sent, then "looped back" and measured at the same end.

12. Troubleshooting Terms End-To-End Testing Testing from both ends of a line. A signal is sent from one end, then measured at the far end.

13. Analog Troubleshooting Tools

14. Butt Set Telephone Line Test Set Telephone Lineman's Test Set Line Test Set Handset Lineman's Handset

15. TS-22 Butt Set

16. TS-19 Butt Set

17. TS-22A Data Safe Butt Set

18. TS-250 ISDN Test Set

19. TS-1000 ADSL Test Set

20. Load Coil Detector (Model 88)

21. TS-100 TDR Cable Fault Finder

22. 77HP Tone Generator

23. 77M Tone Generator

24. 200EP Probe (Inductive Amplifier)

25. 200B Probe (Inductive Amplifier)

26. TIMS (Transmission Impairment Measuring Set)

27. Troubleshooting Analog Lines

28. Line Level Test Milliwatt test Level test Loss test 1000 Hz tone test

29. Quiet Termination Test Quiet test Noise test

30. Ringback Test An automated system. The tester dials a number at the CO, then hangs up. The CO equipment then calls the number that the tester called from.

31. ANAC Automatic Number Announcement Circuit Dial the ANAC number, and a computer generated voice speaks the number of the line you're testing Often accomplished by Caller ID now ANAC works on unlisted numbers

32. DATU Direct Access Testing Unit Allows you to do user-controlled tone generation tests See next slide, "DAMT"

33. DAMT Direct Access Mechanized Testing Allows you to do user-controlled tone generation tests See previous slide, "DATU"

34. Echo Test Repeats every tone you generate Useful for verifying that you are generating valid DTMF tones

35. Troubleshooting Digital Lines

36. Check Clocking #1 Also called "synchronization" On a T1, improper clocking may produce a "Sync" error light On a T1, improper clocking may produce a high BER (Bit Error Rate)

37. Check Clocking #2 On a voice circuit, improper clocking can be heard on the phone or with a butt set as clicking sounds On a data circuit, improper clocking may show up as random data loss or data errors

38. Bit Error Rate Not always related to clocking Digital equivalent of signal-to-noise ratio S/N ratio can be measured on digital voice circuits in the analog portion BER can be measured on all digital circuits, whether voice or data Causes: line loss, reflection, other

39. ISDN Troubleshooting #1 Verify that the SPID is programmed correctly SPID = Service Profile Identifier Assigned by the service provider Programmed in the ISDN "modem" or terminal adaptor

40. ISDN Troubleshooting #2 Verify that the LDN is programmed correctly LDN = Local Directory Number Assigned by the service provider Programmed in the ISDN "modem" or terminal adaptor

41. ISDN Troubleshooting #3 Verify that the terminator is installed (Contains two 100 ohm resistors: pins 4 & 5, pins 3 & 6)

42. ISDN Troubleshooting #4 Make sure the proper encoding format is programmed For North America,  -law For UK and Europe, a-law

43. ISDN Terminal Adaptor #1

44. ISDN Terminal Adaptor #2

45. ISDN Splitter

46. ISDN Terminator

47. Digital Troubleshooting Tools

48. Spectrum Analyzer #1

49. Spectrum Analyzer #2

50. TDR Time Domain Reflectometer

51. Network Analyzer

52. BERT Bit Error Rate Tester

53. Frame Relay Tester

54. ISDN Tester

55. OTDR Optical Time Domain Reflectometer