China Electronics Technology Instruments AV3672 Series, Руководство пользователя

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4 Measurement Setting
4.7 Setting of Data Format and Scale
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Display the real part of the measurement complex.
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It is similar to the linear amplitude format, but both the positive value and negative value can be displayed.
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Y-axis: no unit.
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Applicable typical measurement: time domain and auxiliary input voltage for maintenance purposes.
g) Imaginary part format
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Only display the imaginary part of measurement data.
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Y-axis: no unit.
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Applicable typical measurement: impedance measurement in design of matching network.
2) Polar coordinate format
The polar coordinate format shown in Fig. 4.24 includes the amplitude and phase information. The vector value can
be read in the following method.
a) The amplitude of any point is determined by the displacement of this point relative to the central point (or zero
point). In the default mode, the amplitude is a linear scale, and the excircle scale is set as 1.
b) The phase of any point is determined by the angle relative to the X-axis.
c) The frequency information can only be read through the marker. The default marker format includes the real part
and imaginary part. The
marker dialog box can be opened in the marker/analysis menu. Other formats can be
selected in the advanced marker menu.
Fig. 4.23 Polar Coordinate Format
3) Smith chart format
Smith chart shown in Fig. 4.25 is a tool to map the reflection measurement data of the DUT into impedance. Each
point of the chart represents the complex impedance composed of the real resistance (R) and virtual reactance (±jX).
The resistance, reactance, equivalent capacitance and inductance can be read through the marker.