The compiled VNAView application for Macintosh requires: The NI-VISA driver. LabVIEW 2014 runtime engine. VNAView application.

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1 VNAView for Macintosh Installing and Getting Started Rev. Jan 19, 2016 for VNAView R5.5 or later Gary Johnson, NA6O The compiled VNAView application for Macintosh requires: The NI-VISA driver. LabVIEW 2014 runtime engine. VNAView application. Alternatively, if you own a copy of the full version of LabVIEW for Macintosh (2014 or later), you may run and modify the source code for VNAView. Installation Procedure 1. Download NI-VISA for Mac OSX driver. You need the version for your OS. For OS 10.8 thru 10.10: 2. Run the NI-VISA installer. Use the default installation. Requires administrator privileges. 3. Download LabVIEW 2014 Runtime Engine for Mac OSX from National Instruments (32 MB) Run the Runtime Engine installer. Use the default installation. Requires administrator privileges. 5. Download VNAView installer from my website. 6. Unzip the archive. You may place the resulting folder anywhere on your hard drive. Start Running and Set Up VISA 1. Turn on your N2PK VNA and connect its USB cable to your Mac. 2. Launch VNAView.app. For simplicity, switch to the VNA Signal Gen window. It will give you quicker results while doing this setup. 3. The very first time you run VNA Signal Gen, you will see a dialog with an error message saying that there is a problem with the VISA resource. Click OK. We will fix that next. 1

2 4. Open Applications: National Instruments: VISA: VISA Configuration.app. When it asks to query for dynamic resources, answer Yes. The window will then look something like this: 5. Note the USB-related device with addresses 0x547::0x1005 (highlighted in the screenshot above). That is your VNA. 6. Double-click that VNA device to bring up the Alias Editor. In the field labeled Alias, type VNA. Click OK. 2

3 7. In the File menu, choose Save NI-VISA Configuration. 8. Unplug the USB cable, and plug it back in again. 9. Run the VNA Signal Gen application again. If it s still up on your screen, click the Run arrow, otherwise re-launch it. If you are lucky, it will work this time, and you re done. If it fails again, try running it again. If it keeps failing, continue with this procedure. 10. Unplug the USB cable, and plug it back in again. 11. Back to VISA Configuration. There should now be your original USB resource, with the VNA alias, and a second very similar resource. Delete the first one. Double-click the second one, and name it VNA, same as before. Choose File >> Save NI-VISA Configuration. 12. NOW... you should be able to run VNAView (or VNA Signal Gen) and it will not fail!. Just to be sure, quit and relaunch it. 13. Quit the VISA configuration application. This complete all the one-time setup procedures. Troubleshooting VISA Setup If the above procedure still doesn t work, there is something that I have seen that you can try. When the VNA is plugged in to a new system for the very first time, the VISA address can come up 0x1004 rather than 0x1005. On your first time thru this process, give the 1004 address the alias VNA, save it, and run the VI. Then go back to VISA Configuration, refresh its window (or restart it), and you should now see TWO resources, the one with 1004 and another with Delete the one with 1004, and give the one with 1005 the VNA alias, and save. After that, it should be reliable. Another thing you can do is cycle the power on the VNA. This erases the USB configuration in the microcontroller. Then start this entire process over. 3

4 Getting Started Now you can run VNAView. In the upper left-hand corner, click the big Run arrow. You may also run the VNA Sig Gen in the same way (only run one or the other at a given time, though). Read the brief instructions in the Config tab of VNAView. They are also shown below. To stop either of the applications, click the red Stop button. To exit all of VNAView, choose VNAView >> Quit (cmd-q) like any other application. When you launch VNAView from the Finder, it will run automatically. If your VNA is not plugged in, you will see an error message similar to the one described under the section where we configured VISA for the first time. Just plug it in, and click the Run arrow. HINT: If the application ever hangs, it s normally a USB error. Exit the application, unplug the USB cable, and plug it back in again. Failure usually occurs because of high sampling rates. Depending upon your system, 110 or 220 Hz may be the highest reliable speed. Basic Instructions Basic Operation This is the compiler-friendly Mac OS X version. It requires USB and NI-VISA to interface with the N2PK VNA. 1. Set Master Clock Freq for your VNA, and choose VISA resource name (this tab). 3. Choose Instrument Mode (top of panel). Note: "S11,S12,S21,S22" mode requires S parameter test set with RF relay. 4. Scan tab: Setup scan parameters as desired. 5. Calibration tab: Click Calibrate button, apply standards per dialog box prompts. It's a good idea to set OPEN Avgs to something like 5 or more to reduce noise. Warning about cal mode mismatch will come on and stay until the first scan is complete. 6. Optionally, save calibration file for later recall. Any file name will do. Scan settings are saved with the cal, so that when you recall a calibration, the instrument will automatically be set up the same way. 4

5 7. Turn on Scan button. Acquiring light goes on and Samples increase to show progress. There are N*2 samples (I and Q) for each freq where N is the number of ADC Avgs. Scanning is continuous until you turn off Scan. Other Indicators A warning indicator will come on after a scan if calibration type does not match instrument mode. Calibration State indicator will update after a scan to show if interpolation is in effect. An informative indicator (ATTEN) will appear any time the attenuator is >0 db. Data Display Tabs Raw Display tab shows raw ADC magnitudes in Volts (for debug, mostly). S Display tab shows mag/phase of any of four available S parameters. Analysis tab has graphs for misc. computed parameters. Smith tab has Smith chart for S11 or S22, as available. Data on the display tabs may be saved to tab-delimited text files. Just click the associated Save button. Analysis Notes To directly measure impedance of a component, configure the VNA for S21 and insert the DUT in series between RF Out 1 and Detector 2. On the Analysis tab, view Fwd Transimpedance. That will be the DUT impedance in ohms, exactly as any impedance measurement would display. You can also configure the VNA for S11 and install the DUT as the load on the bridge. On the Analysis tab, view Zin Magnitude. This shunt method will give you the same answer as the S21 (series) method. Generally, the series method is best for high-z (>> 50 ohms), while shunt is better for low-z. To measure an inductor, use the series method, and view Series Inductance (uh). You can also look at Series Q. To measure a capacitor, use the shunt methods, and view Shunt Capacitance (pf). Note that the values will only be correct for ideal components. For non-ideal components and networks, use the RLC Fit featues. Directions are on the RLC Fit tab. Help Tip strips and context help (ctrl-h) are active on many controls and indicators, and all subvis have some documenation. You can copy and paste this text into another application. Help on using graph controls: 01/TOC21.htm Comments and bug reports to Gary Johnson, NA6O <gwj@wb9jps.com> This software is for hobbiest use only. You are free to modify and distribute it as you desire. It is "BeerWare:" If you like the software and we should ever happen to meet, you may optionally buy me a beer. 5