Rohde & Schwarz R&S FPH, Руководство пользователя

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Spectrum Analyzer Mode
R&S ® Spectrum Rider FPH
162 User Manual 1321.1011.02 ─ 06.00
If you know the frequency of the signal you are measuring, it is best to match the cen-
ter frequency to the signal's frequency. If you are investigating signals, e.g. harmonics,
that are within a particular frequency range, the best option is to enter a start and stop
frequency to define the span.
●
Defining the Center Frequency ............................................................................. 162
● Defining a Frequency Step Size ............................................................................162
● Setting a Frequency Offset ................................................................................... 163
● Defining a Start and Stop Frequency ....................................................................163
● Setting the Span ....................................................................................................164
6.2.2.1 Defining the Center Frequency
The center frequency represents the frequency at the center of the horizontal axis in
the diagram area.
1. Press the [FREQ] key.
2. Select the "Center Freq" softkey.
The R&S Spectrum Rider opens an input field to define the center frequency.
3. Enter the center frequency you need.
The frequency you have entered becomes the new center frequency.
Special touchscreen gesture
Alternatively, define the center frequency by swiping horizontally across the touch-
screen to change the center frequency.
See
Chapter 4.2.1, "Change Center Frequency" , on page 88.
While adjusting the center frequency, you may obtain a value that is outside the R&S
Spectrum Rider maximum span. If this happens, the R&S Spectrum Rider automati-
cally reduces the span.
6.2.2.2 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] key.
2. Select the "CF Step Size" softkey.
The R&S Spectrum Rider 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.
Configuring Spectrum Measurements