Mohr CT100B Series, Руководство оператора

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List of Figures
3.1. Example nameplate label found on back of a CT100B. . . . . . . . . . . . . . . . . 11
3.2. Diagram of the CT100B front panel. . . . . . . . . . . . . . . . . . . . . . . . . . . 12
3.3. Diagram of the rear panel of the CT100B/CT100HF. . . . . . . . . . . . . . . . . . 14
3.4. Screenshot showing typical features of the CT100B. . . . . . . . . . . . . . . . . . 16
3.5. Clip lead adapter and controlled impedance adapter . . . . . . . . . . . . . . . . . 28
3.6. Screenshot showing AUTOFIT result. . . . . . . . . . . . . . . . . . . . . . . . . . 29
3.7. Use of the
HORIZONTAL SCALE
knob to improve Vp accuracy. . . . . . . . . . . 30
3.8. Final Vp of the cable. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
3.9. Smoothed vs. unsmoothed traces at very small vertical scales . . . . . . . . . . . . 31
3.10. A small fault in a long cable. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
3.11. AUTOFIT cable. The cable termination is a short. . . . . . . . . . . . . . . . . . . 33
3.12. Vertical scale used to emphasize cable fault. . . . . . . . . . . . . . . . . . . . . . . 33
3.13. A zoomed in view of the cable fault . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
3.14. Relative distance measurement between two small impedance “faults” caused by
BNC connectors. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
3.15. Multi-segment cable segment with Vp of 0.400 . . . . . . . . . . . . . . . . . . . . . 35
3.16. Multi-segment cable segment with Vp of 0.850 . . . . . . . . . . . . . . . . . . . . . 36
3.17. Scan progress display with Cancel button. . . . . . . . . . . . . . . . . . . . . . . . 36
3.18. Scan of a portion of a cable, zoomed-in vertically. . . . . . . . . . . . . . . . . . . . 37
3.19. Selecting the live trace. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
3.20. Selecting a scanned trace. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
3.21. Selecting a difference trace. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
3.22. Using the on-screen keyboard. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
3.23. Loading a trace. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
3.24. A trace that passes the mask test . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
3.25. A trace that fails the mask test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
3.26. Envelope Plot with Fill Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
3.27. Envelope Plot with Probability Density display. . . . . . . . . . . . . . . . . . . . . 45
3.28. Envelope Plot with Fill Mode, showing the range of impedance values . . . . . . . 46
3.29. Difference trace . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
3.30. First-derivative trace . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
3.31. Resistive cable loss correction, before. . . . . . . . . . . . . . . . . . . . . . . . . . 49
3.32. Resistive cable loss correction, after. . . . . . . . . . . . . . . . . . . . . . . . . . . 49
3.33. S
11
return loss plot. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
3.34. S
11
between cursors bracketing an SMA barrel adapter on the TDR trace. . . . . . 53
3.35. S
11
between cursors with tightened connector . . . . . . . . . . . . . . . . . . . . . 53
3.36. S
11
between cursors with loosened connector . . . . . . . . . . . . . . . . . . . . . . 54
3.37. Using a phase stable cable to improve S-parameter measurements . . . . . . . . . . 55
3.38. Smith chart representation of open fault . . . . . . . . . . . . . . . . . . . . . . . . 55
3.39. Smith chart representation of short fault . . . . . . . . . . . . . . . . . . . . . . . . 56
3.40. Smith chart representation of a 50 ohm resistive load . . . . . . . . . . . . . . . . . 56
3.41. Smith chart of reactive 200 ohm load . . . . . . . . . . . . . . . . . . . . . . . . . . 57
3.42. Normalized trace showing short fault in a 50 ohm cable. . . . . . . . . . . . . . . . 57
CT100B TDR Cable Analyzers Operator’s Manual xiii