User guide

To convert from Frequency Domain to Distance to Fault, follow these steps:
Step1. Capture a plot or load a previously saved plot.
Step2. Click the
Distance-to-fault button on the toolbar (or choose Distance-to-Fault
from the Tools menu). A dialog will open allowing you to specify the cable pa-
rameters, start distance, and stop distance. The cable type may be selected from
the pull-down list. Selecting a cable from the list automatically sets the propaga-
tion velocity and insertion loss. To manually enter the dielectric constant and in-
sertion loss, select the Custom cable type from the top of the list. Click
OK when
finished. A new window will open showing the converted plot.
Step3. Use the cursor to read out values shown in the bottom tray of the PC screen, at
each point along the DTF trace. Maximize the plot window for best cursor reso-
lution.
NOTES: The distance units (meters or feet) can be changed by selecting De-
fault Plot Settings from the Settings menu.
The stop distance entry must be less than or equal to the maximum un-aliased
range (D-Max), and the start distance must be less than the stop distance.
Smith Chart
The Smith Chart is a commonly used graphical format for the analysis of the impedance of
transmission lines. It can be a useful tool for fine tuning an antenna system.
Handheld Software Tools can convert the following types of plots to Smith Charts:
q
Return Loss (Frequency Domain)
q
VSWR (Frequency Domain)
To convert a plot to a Smith Chart:
Step1. Capture a plot or load a previously saved Return Loss or VSWR plot.
Step2. Click the
Smith Chart button on the toolbar (or choose Convert to Smith Chart
from the Tools menu). A new window will open showing the plot in Smith Chart
form.
Step3. To read values from a Smith Chart, move the mouse pointer over a data point.
When the mouse pointer turns into a hand, click once with the left button. A
pop-up window will appear with various measurement data.
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Chapter 7 Handheld Software Tools