HP 54710A User's Reference Manual page 81

Acquisition Menu
Record Length
Figure 3-9 shows a 256-point record length, a 50-ns/div time base scale, and a
2-GSa/s sample rate. Notice that the entire waveform record is displayed.
The 2-GSa/s sample rate fills up the 256-point waveform record quickly,
which increases measurement throughput, but does not leave much data for
the oscilloscope to display.
1
(256 Points) = 128 ns of data
⁄
GSa
2
s
Because the time base is set to 50 ns/div and the screen is 10 divisions wide,
the screen can display up to 500 ns of data. In this example, there is 128 ns
of data in the waveform record, which is not enough data to fill the screen. In
order to fill the screen, either increase the waveform record length to 1000 to
capture more data or change the time base scale to 12.8 ns/div.
Figure 3–9
Manual sample rate and manual record length
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