Quick Start guide
After opening the software you will see a window "live measurements", where all measurements are performed. There are other windows that can be opened using the menu bar:
t is absolutely required that you create a valid calibration prior to your first measurement. For this, click on "Calibration". The calibration window opens.
Select with "From", "To" and "Steps" the frequency span and number of measurement steps for your calibration. These number should be around the values you want to use for your measurement later. For improved accuracy, increase "Averaging" for example to 5. Please note, that the measurement will take 5 times longer now but will have a higher accuracy.
For a general "all-round" calibration , you could start with
Adc AVG: 10
For enhanced sensitivity in a limited frequency span the following setting can be used:
Start: lower frequency of the region of interest
Stop: upper frequency of the region of interest
Adc AVG: 10
Now you need to perform one scan for each of the calibration standards:
- Open : Connect your "Open" calibration standard to the DUT port and press "Scan". If you are happy with the curve recorded clock "Use as "open".
- Short and Load : Proceed the same way for your "Short" and your "Load" standard. Then save your calibration by clicking on "save calibration" and afterwards click on "Use and close"
It is always a very good idea to check if your calibration procedure has been successful . You can do this by measuring S11 with open/short/load standard connected:
Open the "live measurement" window, enter your desired scan parameters (From, To, Steps) , ideally the same you used for the calibration and press scan.
Do this measurement for all three standards (Open, Short, Load) and import the data into a Smith Chart: Click on Smith Chart to open a new Smith Chart and click "Import Live" to import from "live measurement".
Plotted in a Smith Chart the three standards should look like this:
If the open, short or load graphs are not at the right positions, your calibration failed and you will not be able to do proper measurements. Make sure you have followed the instructions above and
, if you are not able to resolve the problem.
Now you are ready for your first measurement:
Open the "live measurement" window, enter your desired scan parameters as you did in calibration and press scan. PocketVNA now scans and presents your first measurement on the screen.