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R&S FSH
Cable Measurements
1145.5973.12 4.107
E-11
If the cable attenuation exceeds 10 dB, the R&S FSH
outputs a warning indicating that the cable attenuation
is too high. It also indicates the maximum
recommended cable length for obtaining accurate
results.
Pressing CONTINUE accepts the entry.
Selecting the frequency range
In the default setting, the R&S FSH automatically selects the frequency range around the set center
frequency on the basis of the cable length and cable model. The R&S FSH selects a frequency range
that enables maximum length resolution.
Particularly with relatively short cables, the frequency range in which the cable is specified may then be
exceeded. Therefore, the R&S FSH allows the user to define the frequency range in which the distance-
to-fault measurement is carried out. However, the length resolution of the measurement is reduced by
using smaller frequency ranges.
When setting the frequency range, users are advised first to set the span and then the center
frequency. This prevents a message from being output stating that the desired center frequency cannot
be set for the span currently being used for the distance-to-fault measurement.
Press the SPAN key.
The R&S FSH displays the span menu for the DTF
measurement. If automatic setting of the span is
selected, the AUTO SPAN softkey label is highlighted
in green. If the AUTO SPAN softkey is pressed, the
R&S FSH sets the span for the best length resolution.
If the required span is too large for the current center
frequency, the R&S FSH sets the center frequency to
the smallest possible frequency.
Press the MANUAL SPAN key.
Set the required span by using either numeric
entry, the cursor keys or the rotary knob.
Confirm the setting with the ENTER key or by
again pressing the MANUAL SPAN softkey again.
The minimum span that can be set is either 1/10 of the span automatically set by the R&S FSH in the
case of AUTO SPAN or 200 MHz (whichever is smaller). Spans larger than the ones set by the
R&S FSH with AUTO SPAN are not allowed. If an attempt is made to set smaller or larger spans, the
R&S FSH responds with "Minimum reached" or "Range exceeded".