5-4
IM DL350-01EN
Sample Rate
If you change the time scale, the sample rate also changes. The sample rate is the number of samples-per-
second (S/s).
* If the sample rate is comparatively low with respect to the input signal frequency, the harmonics contained in
the signal are lost. When this happens, some of the harmonics will be misread as low-frequency waves due
to the effects described by the Nyquist sampling theorem. This phenomenon is called aliasing. You can avoid
aliasing by acquiring waveforms with the acquisition mode set to Envelope.
Aliased signal
Input signal
Sampled points
Time Scale and Roll Mode Display
When the trigger mode is Auto, Single, or On Start and the time scale is 100 ms/div or longer, instead of updating
waveforms through triggering (update mode), the instrument displays the waveforms in roll mode. In roll mode,
waveforms scroll from right to left as new data is captured and the oldest values are deleted from the screen.
This allows waveforms to be observed in the same way as on a pen recorder. Roll mode is useful for observing
signals with long repeating periods and signals that change slowly. It is also effective when you want to detect
occasional glitches (pulse signals in the waveform).
You can use auto setup to automatically configure the appropriate settings (such as vertical axis, horizontal
axis, and trigger settings) for the input signal. This feature is useful when you are not sure what type of signal
will be applied to the instrument. The auto setup feature will not work properly on some input signals. Also,
there are some modules with which the auto setup feature cannot be used.
Acquisition Time, Record Time, Acquisition Length, Record
Length (Acquisition Time, Record Time, Acquisition Length,
Record Length)
These are settings in recorder mode.
• When the
Data is acquired for the specified time.
• When the
is Memory, Save on Stop, or SD Numeric Recording
The acquisition time (Acquisition Time) is displayed.
Selectable range: 10s to 20day
• When the acquisition method is SD Recording
The record time (Record Time) is displayed.
Selectable range: 10s to 50day
5 Waveform Acquisition