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MegaZoom Concepts and Oscilloscope Op eration
Acquisition Modes
Average Mode
Averaging lets you average multiple triggers toge ther to reduce noise and
increase resolution. Averaging of multiple triggers requires a stable trigger. The
number of triggers being averaged is displayed in the # Avgs softkey.
Turn the Entry knob to set the number of averages (# Avgs) that best
eliminates the noise from the displayed wav eform.
The number of averages can be set from 1 to 16383 in powers-of-2
increments. The higher the number of averag es you set, the more noise
reduction and resolution enhancement will be accomplished.
Smoothing (# Avgs=1) or High-resolution mode
The term smoothing is an oversampling technique used when the digitizer
sampling rate is faster than the rate at which samples are being stored into
acquisition memory. For example, if the oscilloscope is sampling at 200MSa/s,
yet storing the samples at 1MSa/s, it needs to store only 1 out of every 200
samples. When smoothing is used, the slower the sweep speed, the greater the
number of samples that are averaged together for each display point. This tends
to reduce random noise on the input signal, which produces a smoother trace
on the screen.
# Avgs Bits of resolution
18
49
16 10
64 11
256 12