3
Displayed Frequency Range
:
Displayed in the lower left of the screen, they indicate the frequency
endpoints
actually displayed on the chart
. The trace actually has points not visible on the chart, and
these can be viewed by enabling a cursor, and rolling the cursor past the left or right edge of the
chart, which will cause the graph to scroll left or right. This will also cause the frequencies displayed
to be updated as appropriate. When there are no cursors enabled, the upper frequency is displayed
near the lower right corner of the chart.
Cursor Frequency:
For each cursor enabled, the cursor's frequency is displayed as shown. In the
above illustration, the cursor frequency is displayed highlighted-- indicating that it is selected, and can
be moved using the LEFT & RIGHT arrow buttons. As the cursor is moved, this frequency value is
updated.
Left & Right Scale Cursor Values:
Immediately to the right of the cursor frequency, are the Scale
Cursor Values. These are the measurements for the frequency at which the cursor is positioned.
They are updated for every sweep.
It should be noted, that all of the above elements are common to both the VNA and SWR mode wide-
format screens. As previously mentioned, the MRI-3000's screen is composed of the chart area, and
the sidebar area (on the left side of the screen). In VNA mode, the sidebar in wide chart format is
made up of the following indicators (all of which represent their respective measurements
at center
frequency
):
Impedance Magnitude:
Labeled "Z-Mag", this is the vector sum of the impedance's resistance and
reactance components. This value i
s in Ω.
Impedance Angle:
Labeled "Z-Ang", this is the relative phase shift of the impedance, in degrees.
Resistance:
Labeled "Rs" is the resistive component of the impedance, in Ω.
Reactance:
Labeled "Xs" is the reactive (i.e. complex) component of the mea
sured impedance, in Ω.
Reactance values can be positive or negative.
Capacitance / Inductance:
Labeled "C/L", this indicator calculates the value of the equivalent series
or parallel reactive component to give the measured complex impedance. If the reactive part of the
impedance is negative, this value will be represented as a capacitance value. If it is positive, an
inductance value will be displayed. The RLC model used in the calculation can be selected from the
'OTHER OPTIONS' menu, on Page 15.