Hioki 8860-50, Instruction Manual

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Appendix 4 Supplemental Technical Information
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This instrument converts analog input signals into digital values which are then
processed internally as digital (numerical) values. This A/D conversion process
is called sampling.
Sampling repeatedly measures the size of the input signal at a specific interval
(the sampling period).
The rate of measurement is called the sampling rate.
Sampling units are [S/s] (read as samples-per-second)
This is the number of samples taken each second, and is the inverse of the sam-
pling period. (1/T)
If the signal to be measured changes too fast relative to the sampling period,
beginning at a certain frequency, non-existent slow signal fluctuations are
recorded. This phenomena is aliasing.
With the Memory function, the sampling period can be significantly affected by
the timebase setting, so care is necessary to avoid aliasing when selecting the
timebase.
Because the timebase determines the measurement frequency limit, the fastest
possible timebase setting should be used.
When the signal can be recorded repeatedly, the auto-ranging function (p. 74)
may be used to select the optimum timebase.
Appendix 4 Supplemental Technical Information
Appendix 4.1 Sampling
Sampling Period
Measurement
Time
Sampling Points
Appendix 4.2 Aliasing
Sampling Period
Measured Waveform
Aliasing occurs when the sampling period is longer
than half of the input signal period.
Actual Input Signal
Sampling Points