Kroks ARINST VNA-PR1, Manual

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2-port vector network analyzer ARINST VNA-PR1
12
9.2.1. Enter the Scan section of the main menu of the device. Menu for setting the parameters of the
frequency range Scan is shown in Figure 9.2
9.2.2.
Scan menu buttons:
Center
– setting the center frequency of the scanning range.
Span
– scanning range of frequencies.
Start
– setting the initial frequency of the scanned frequency range.
Stop
– setting the final frequency of the scanned frequency range.
BW
– selection of the bandwidth of the digital IF filter.
Points
– selecting the number of scan points.
DTF range settings
– setting the parameters of the horizontal scale of the DTF plot. Switching to the
time or distance settings of the DTF plot.
Back
– exit to the main menu.
9.2.3. The frequency parameters
Center , Span , Start and Stop are set by entering a numerical value
in the opened submenu, as shown in Figure 9.3. The resolution of setting the frequency parameters is
100 Hz in the frequency range up to 100 MHz and 10 kHz in the range from 100 to 6200 MHz. Enter the
numerical value of the frequencies in
MHz or GHz and press the corresponding button. To delete incor-
rect or previously entered values, press < ( Delete ). Press
×
( Cancel ) to exit the menu without entering
values.
Figure 9.3 - Entering numerical values of frequency parameters
9.2.4. There are three ways to set frequency parameters:

By entering the initial Start and final Stop frequencies, the center frequency Center is automati-
cally assumed to be equal to their half-sum. The Span frequency range is automatically set
equal to the difference between the final and initial frequencies.

Setting the Center frequency and the frequency range of scanning Span . In this case, the Start
and Stop frequencies will be set automatically as
Center ± Span / 2
.

Loading custom settings from the Presets menu.
If the frequency entered by the user is outside the operating range, a warning is displayed on the
screen.
9.2.5. In the
BW menu (figure 9.4), the bandwidth of the digital IF filter is selected. The narrower the
bandwidth of the digital filter, the higher the signal-to-noise ratio and, consequently, the higher the meas-
urement accuracy. As the bandwidth decreases, the scan time increases.
Reducing (narrowing) the bandwidth by 10 times will lead to an increase in the voltage signal-to-noise
ratio by 3 times (or 10 dB) with an increase in scan time by 10 times.