Spectrum Analyzer Mode
R&S
®
Cable Rider ZPH
213
User Manual 1321.0950.02 ─ 07
Special touchscreen gesture
Alternatively, define the center frequency by swiping horizontally across the touch-
screen to change the center frequency.
See
Chapter 5.1.1, "Change Center Frequency"
,
on page 89.
While adjusting the center frequency, you may obtain a value that is outside the R&S
Cable Rider ZPH maximum span. If this happens, the R&S Cable Rider ZPH automati-
cally reduces the span.
8.2.2.2
Defining a Frequency Step Size
If you set the center frequency with the rotary knob, the distance of each step that you
take depends on the span. With the rotary knob, the smallest possible step is a pixel.
As the trace consists of 711 pixels, each step is equal to 1/711 of the span.
You can set another step size.
1. Press the [FREQ/DIST] key.
2. Select the "CF Step Size" softkey.
The R&S Cable Rider ZPH opens a submenu that contains possible step sizes.
● "0.1 x Span"
The step size equals 10 % of the span or 1 division of the horizontal axis.
● "step = Center"
The step size equals the center frequency.
This step size is ideal for measurements on harmonics. When you increase or
decrease the center frequency, the center frequency automatically moves to
the next harmonic.
● "Manual"
An entry box is displayed to define the value.
This step size makes it easy to investigate a spectrum with frequencies at con-
stant intervals.
3. Select the step size you need from the menu.
The R&S Cable Rider ZPH adjusts the step size accordingly.
If you set the step size to 10 % of the span or to the center frequency, the R&S Cable
Rider ZPH sets the step size internally. Manually defining the step size opens an input
field to define the step size.
8.2.2.3
Setting a Frequency Offset
For measurements on frequency converters such as satellite downconverters, it is
often convenient to reference the results to the frequency before conversion. For this
purpose, the R&S Cable Rider ZPH offers a frequency offset that arithmetically shifts
the center frequency to higher or lower frequencies. Thus, the R&S Cable Rider ZPH
displays the input frequency of the DUT.
Configuring Spectrum Measurements
