82 Keysight N9915-90020 User’s Guide
TDR (Time Domain Reflectometry) - Option 215
TDR Measurement Settings
—Then DTF Cable Specifications
— Select Cable Corr
— Auto Use Cable Loss and Velocity Factor values from a Cable file. See
“How to Edit, Save, and Recall a Cable File” below. This will overwrite
a manually-entered value.
—
Man (Default setting) Manually enter a value for Cable Loss and
Velocity Factor.
—Then:
—
Velocity Factor Using the numeric keypad, enter a value between
0.01 and 1. Then press Enter
.
—
Cable Loss Using the numeric keypad, enter a positive Cable Loss
value in dB/m, then press Enter
.
How to Edit a Cable File
The FieldFox includes many predefined cable files with the manufacturer’s
specifications. You can edit these files or create new cable files using the
following procedure or using the FieldFox Data Link Software.
The Cable correction data survives a Mode Preset and Preset.
With a TDR measurement present:
—Press Meas Setup 4
—Then DTF Cable Specifications
—Then Edit/Save/Recall Cables
—Press
New Cable then Yes to clear all data from the existing DTF Cable
table and reset header information to default settings.
—Then Edit Cable to open the Cable Editor.
— Then use the arrows to select a field,
— When editing Cable Description information, press Edit
then modify
the selected field using the FieldFox labeler.
— When editing Frequency/Loss pairs, enter numbers using the
numeric keypad, then select a frequency suffix. Then
Enter. Learn
more about “How the Freq/Loss pairs are applied” below.
— Optionally choose from the following:
—
Previous / Next Page
Quickly scrolls through pages of Freq/Loss
data.
— Add Data
Add a blank Freq/Loss pair to the table,
—
Delete/Clear then:
— Delete Row Remove the selected Freq/Loss pair from the table.