Digital Storage Oscilloscope 48
again to acquire another waveform.
When you acquire an analog signal, the oscilloscope will convert it into a digital one.
There are two kinds of acquisition: 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 setting of time base.
Normal:
In this acquisition mode, the oscilloscope samples the signal in evenly spaced
intervals to establish the waveform. This mode accurately represents signals in most
time. 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, you should use the Peak Detect mode to acquire data.
Peak Detect:
In this acquisition mode, the oscilloscope gets 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 those
narrow pulses that may have otherwise been missed in Normal mode. However, noise
will appear to be higher in this mode.
Average:
In this acquisition mode, the oscilloscope acquires several waveforms,
averages them, and displays the resulting waveform. You can use this mode to reduce
random noise.
Equivalent Acquisition: This kind 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 tiny 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. 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 SEC/DIV knob to adjust the time base to a horizontal scale that suits
your purpose.
Push the
uTILITY
button and press
Acquire
softkey to set the acquisition parameter.
