GW Instek GDS-800 Series User Manual User Manual

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GDS-800 Series Digital Storage Oscilloscope Operation Manual

CH1-CH2: Waveform of channel 1 minus waveform of channel 2.

The position of CH1+CH2/CH1-CH2 mathematical waveform can be adjusted by

rotating the VARIABLE knob. The math position indicator

(located on the left

side of the LCD graticule) will change the position simultaneously. The

information of mathematical division and unit will also display on the math menu

bar.

FFT: The details of FFT operations are following:

FFT

Operation: Push the MATH button to select the FFT function. The Source Channel

and Window algorithm can be selected. Press MATH pushbutton again to disable

FFT spectrum display.

Source CH1/CH2: Selects the channel which assigned as the FFT spectrum.

Window Rectangular/Blackman/Hanning/Flattop:

Window Rectangular: Transform to rectangular windowing mode. This

windowing mode is suitable for transient analysis.

Window Blackman: Transform to Blackman windowing mode. The peak

resolution of Blackman windowing is not as fine as Hanning windowing,

however, the response shape flares out less at low levels and rejection of

sidelobes is better.

Window Hanning: Transform to Hanning windowing mode. User can

acquire higher frequency resolution by using this windowing mode.

Window Flattop: Transform to flattop windowing mode. This mode can

obtain higher magnitude accuracy.