Keysight Technologies 3458A Guide D'utilisation page 210

5 Digitizing
For this example, on the first period of the input signal, the multimeter takes a
burst of 5 samples. On the second period, the multimeter delays the trigger point
by 5 µs and takes another burst of 5 samples. On each of the remaining two
periods, the multimeter delays the trigger point by another 5 µs and takes a burst
of 5 samples. As shown in
proper sequence, the result is one period of the input signal consisting of 20
samples spaced at 5 µs intervals. In this example then, the effective sampling rate
is 200,000 samples per second.
Figure 5-10
Figure 5-11
210
Figure 5-11, when all the samples are arranged in the
Sub-sampling example
Composite waveform
Keysight 3458A User's Guide