Spectrum Analyzer Mode
R&S
®
Cable Rider ZPH
170
User Manual 1321.0950.02 ─ 07
For more information, see
Chapter 5.9, "Managing Datasets"
,
on page 107.
8.1.2.2
Setting the Reference Level
The reference level is the power level that the R&S Cable Rider ZPH expects at the RF
input. When selecting the reference level, make sure that you do not overload the R&S
Cable Rider ZPH by applying a signal whose power exceeds the maximum reference
level.
As the power is measured with a small resolution bandwidth compared to the signal
bandwidth, it is still possible to overload the R&S Cable Rider ZPH, even if the trace is
within the measurement diagram. To prevent an overload, perform the measurement
with the largest resolution bandwidth possible using the peak detector. If you set these
parameters, it is not possible for the trace to exceed the reference level.
To simplify operation and to prevent incorrect measurements, the R&S Cable Rider
ZPH has an automatic routine for setting the reference level.
1. Press the [MEAS] key.
2. Select the "Level Adjust" softkey.
The R&S Cable Rider ZPH performs a measurement to determine the optimal ref-
erence level.
It uses a resolution bandwidth of 3 MHz, a video bandwidth of 3 MHz and the peak
detector. After finishing the automatic measurement, the R&S Cable Rider ZPH
sets the optimal reference level.
8.1.2.3
Setting the Channel Bandwidth
The channel bandwidth specifies the frequency range around the center frequency,
over which the R&S Cable Rider ZPH performs the power measurement.
1. Press the [MEAS] key.
2. Select the "Channel BW" softkey.
The R&S Cable Rider ZPH opens an input field to specify the channel bandwidth.
3. Enter the channel bandwidth you required.
The R&S Cable Rider ZPH sets the appropriate span for the channel bandwidth
that you have entered (span = 1.2 x channel bandwidth). This ensures that no
incorrect channel power measurements are made.
The minimum channel bandwidth that you can set is 833 Hz at a span of 1 kHz.
Performing Spectrum Measurements
