15 MS6000-EU-EN V1.4 8/12
3.14 Data Acquisition
When an analog signal is acquired, the oscilloscope will convert it to a digital one. There are two kinds of
acquisitions: Real-time acquisition and Equivalent acquisition. The real-time acquisition has three
modes: Normal, Peak Detect, and Average. The acquisition rate is affected by the time base.
Real-Time Acquisition:
Normal: In this mode, the oscilloscope samples the signal in evenly spaced intervals to establish the
waveform. This mode accurately represents signals in most instances. However, it does not acquire
rapid variations in the analog signal that may occur between two samples, which can result in aliasing
and may cause narrow pulses to be missed. In such cases, use the Peak Detect mode to acquire data.
Peak Detect: In this mode, the oscilloscope obtains the maximum and minimum values of the input
signal over each sample interval and uses these values to display the waveform. In this way, the
oscilloscope can acquire and display narrow pulses that may have otherwise been missed in Normal
mode. However, noise will appear to be higher in this mode.
Average: In this mode, the oscilloscope acquires several waveforms, averages them, and displays the
resulting waveform. Use this mode to reduce random noise.
Equivalent Acquisition:
This type of acquisition can be utilized for periodic signals. In case the acquisition rate is too low when
using the real-time acquisition, the oscilloscope will use a fixed rate to acquire data with a stationary
(very small) delay after each acquisition of a frame of data. After repeating this acquisition for N times,
the oscilloscope will arrange the acquired N frames of data by time to make up a new frame of data; and
then the waveform can be recovered. The number of times (N) is related to the equivalent acquisition
rate.
Time Base: The oscilloscope digitizes waveforms by acquiring the value of an input signal at discrete
points. The time base helps to control how often the values are digitized. Use the TIME/DIV button to
adjust the time base to a horizontal scale that suits your requirements.
