User manual

Measurements
R&S
®
RTO
146User Manual 1316.0827.02 ─ 06
3. To change the name of a histogram, double-tap the tab label and enter a name for
the histogram using the on-screen keyboard.
4. Select a "Source" for the histogram. The source can be any input signal, math or
reference waveform.
5. Define the histogram "Mode": vertical for an amplitude, horizontal for a time-based
histogram.
6. Define the range of the waveform for which the histogram is to be generated. Enter
the start and stop values in x and in y direction, either as absolute or relative values.
5.2.2.5 Configuring Reference Levels
Some measurements refer to specific reference or signal levels, e.g. rise time/fall time
evaluation or counting pulses. Generally, these settings are determined automatically.
However, for irregular data it may be useful to configure them manually, or to define some
parameters for automatic determination.
In addition to reference and signal levels you can define hystereses for reference levels,
as well as tubes for signal levels. Hystereses are useful for measurements that determine
zero-crossings. Tubes define evaluation ranges for measurements that require high level
or low level detection. If the signal value remains within the defined tubes, it is considered
to be high or low.
Reference levels and intermediate results required for further measurements can be dis-
played in the source diagram.
Example:
For example, data signals may contain intervals where no data is transmitted, so that a
high and low state can not be determined for each acquisition. In this case, you can define
the high and low signal levels manually, in order to evaluate other measurement results.
Furthermore, if the signal levels vary strongly or have large overshoots, the rise and fall
levels may be difficult to determine.
Finally, if fixed levels are configured for the connected device, you can define the signal
levels in the R&S RTO correspondingly and analyze the resulting measurement data.
To determine reference and signal levels automatically
By default, the histogram of the measurement data is evaluated to determine the required
levels automatically. However, you can define several parameters to adapt the evaluation
to your data.
1. From the "Meas" menu, select "Reference Level > Levels" to open the "Measure-
ment" dialog box.
2. Select the "Levels" tab.
Automatic Measurements