R&S ZVH
Spectrum Analyzer Mode (R&S ZVH-K1)
Performing Spectrum Measurements
Operating Manual 1309.6946.12 - 09
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Because the resolution bandwidths of the R&S ZVH are implemented digitally after the
A/D converter, the signal level at the A/D converter can be higher than the level
indicated by the trace, depending on the selected resolution bandwidth.
To prevent the A/D converter from being overloaded, the signal must be measured at
the widest resolution bandwidth and video bandwidth with the peak detector. The trace
maximum then determines the best reference level.
To simplify operation and to prevent incorrect measurements, the R&S ZVH has an
automatic routine for setting the reference level.
► Press the SCALE/AMPT key.
► Press the "Level Adjust" softkey.
The R&S ZVH performs a measurement to determine the ideal reference 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 ZVH sets the ideal
reference level.
4.1.4.4 Using a Trigger
Usually you will apply a trigger when measuring bursts.
If a trigger is active, the R&S ZVH uses the video trigger for TDMA measurements by
default. The video trigger level is at 50 % of the range of the vertical axis but is
variable. This means, the R&S ZVH triggers a measurement if the rising edge of the
burst exceeds this 50 % line.
If the DUT features some sort of trigger equipment, you can also use an external
trigger to trigger measurements.
► Connect the DUT trigger output to the R&S ZVH trigger input.
► Press the SWEEP/BW key.
► Press the "Trigger" softkey.
► Select either the "External Rise" or "External Fall" menu item (rising or falling
edge).
The R&S ZVH activates the trigger and shows the results of the measurement.
It may be that the burst is not completely visible on the display. To correct that and
make the whole burst visible, you can set a trigger delay.
► Press the "Trigger" softkey.
► Select the "Trigger Delay" menu item.
The R&S ZVH opens an input field to define the trigger delay.
► Adjust the trigger delay until the burst is visible inside the vertical lines that show
the measurement range.
