Chapter 5 Software Tools Program
Program Operation
The captured trace on the PC can be scaled and have its limit line, markers, and properties changed. (Click on the Plot Properties icon, or select Plot Properties under the View menu to make these changes.) The operation of the various menus that allow these opera- tions to be accomplished is straightforward. To read about the operation of the menus, refer to the
Fault Location Software
A captured RL or SWR trace can be transformed to a Distance to Fault display. This is use- ful for determining the location of faults, connections, and other discontinuities within the cable.
To transform a plot, select Distance to Fault from the Tools menu (or click on the Distance to Fault icon in the toolbar). A drop down menu will appear that asks you if the DUT is co- axial cable or waveguide.
If coaxial cable is selected, it asks you to supply start and stop distances along with the ca- ble type or propagation velocity and insertion loss values. Tables in Appendix A provide these values for some of the more popular coaxial cables (@ 1000 MHz).
If values are needed at a different frequency, or if you need the exact values for more accu- rate measurement, please contact the coaxial cable manufacturer. Coaxial cables may be added to the list be editing the cables.lst file. Follow the existing format to enter the data to the list. Loss is entered in dB/m only.
The distance may be entered in feet or meters. Propagation velocity is used for coaxial ca- ble. The units may be changed by selecting Default Plot Settings under the Settings menu and changing Measurement Units.
After supplying the needed information and clicking OK, a new plot will open showing coax match vs. distance.
Smith Chart Software
After obtaining a frequency SWR or RL plot on the computer display, click the Smith Chart icon. Read the Help file to see how this feature functions (under Smith Chart and Data Readout).
