koban KMOS-01 Guía De Usuario página 250

Note:
•
DC component or deviation existed in signal may cause error or deviation in FFT waveform
component part. Select DC coupling mode to reduce AC component.
•
Nyquist frequency: for waveform, of which highest value ups to F, sampling rate of 2F must
be adopted to rebuild the waveform, that is also called Nyquist criteria, "F" means Nyquist
frequency, "2F" means Nyquist rate.
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2 11 Signal Capture System
•Real-time sampling: the memory space should be full for every sampling. Real-time sampling
rate ups to 50MSa/s.
•The system is under default continuous sampling state after startup, press "HOLD" if user
wants to take static measurement, press the same button again to turn back to continuous
sampling state.
•"REC" button: if the user needs the oscilloscope to take sample of enough data to analyze
a series of numbers, press "REC", the oscilloscope may continuously take data sample of
10 pages for measurement analysis.
•Time base: the oscilloscope takes sample of input signal values at discontinuous points to
digitalize the waveform. Frequency of value digitalization can be controlled by adopting time
base. Press " ", adjust the time base to a horizontal level to satisfy user's needs,
•False wave phenomenon: if the speed of sampling is not fast enough, causing inaccurate
waveform records, "false wave phenomenon" occur. In this case, the oscilloscope displays
the waveform by a frequency which is below actual input waveform's frequency, or triggers
and displays unstable waveform. Therefore, press "AUTO" to auto search for the first
measurement of new signal, to confirm the basic frequency of this signal.
actual high
frequency waveform
low frequency
waveform caused by
false wave phenomenon
sampling point
False wave phenomenon
Oscilloscope Section
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