Cable and Antenna Test Mode
R&S
®
Cable Rider ZPH
147
User Manual 1321.0950.02 ─ 07
Dedicated DTF frequency
The "Dedicated DTF Frequency" menu item defines whether the frequency (DTF Start
Freq, DTF Stop Freq, DTF Center Freq, DTF Span) settings in DTF measurement are
coupled to frequency (Start, Stop, Center, Span) settings in other measurements in
CAT mode. When set "Off", the frequency (start, stop, span) settings are coupled
across all measurements in CAT mode.
See
"Setting a dedicated DTF frequency"
on page 148.
7.2.2.1
Setting the Frequency Range for DTF Measurements
In the default setting, the R&S Cable Rider ZPH automatically selects a center fre-
quency of 1 GHz and a distance of 50 m. The R&S Cable Rider ZPH optimizes the set-
tings for the best resolution, if you change the stop distance.
If you have to keep the current frequency settings, it is best to define a manual span.
Setting the frequency span
When setting the frequency range, it is best to first set the span and then the center
frequency.
There are three different span modes in the DTF measurement:
●
Manual
Setting for span is defined manually. However, the maximum span that can be set
depends on the maximum cable distance defined.
●
Auto
The best span is automatically calculated for the best length resolution.
●
Coupled
The frequency parameters are coupled with the
Return Loss
measurement, with
the maximum cable distance adjusted for the best resolution. This mode is useful
when you switch between the
Return Loss
and
DTF
measurements.
1. Press the [FREQ/DIST] key.
2. Select the "DTF Span" softkey.
The R&S Cable Rider ZPH opens a submenu to specify the frequency span.
By default, the R&S Cable Rider ZPH automatically calculates the best span ("Auto
Span") for the best length resolution. If the required span is too large for the current
center frequency, the R&S Cable Rider ZPH sets the center frequency to the small-
est possible frequency.
3. Select the "Manual Span" menu item.
The R&S Cable Rider ZPH opens an input field to specify the frequency span.
4. Enter the span you require.
The R&S Cable Rider ZPH sets the new span. Note that the maximum span you
can set depends on the maximum cable distance you have defined and is never
greater than the span calculated by the "Auto Span" function. The minimum span
that you can set is 10 MHz.
Configuring Cable and Antenna Tests
