I’ve had it for about a year now and I can now say I truly love it. It’s from China and I took a real risk in buying it, but the product works great as a hobby VNA.

When I was shopping for a VNA, I spent a lot of time on eBay looking for used VNAs. In my price range I found a lot of old Keysight boxes that work up to 3 GHz. I was very tempted, but when I came across the KC901V I saw I could get a portable VNA that works up to about 7 GHz! I took a chance and bought it.

I have not been disappointed. There are a few quirks, but the interface works great and the metal body makes the whole thing feel solid. Support is good too! I had an issue with saving data to an SD card and e-mailed the guys; they were back to me within an hour and I got it worked out (it was simple and it was my fault).

Also, there is a nice ethernet interface which allows me to control the device from my computer. There is a caveat with it, you can only grab raw data that has not been corrected by calibration. This means you have to write something to do calibration for you. But, after a few hours, I figured out how to get MATLAB talking with the VNA so I can make nice graphs like the one below.

Before you rush to get one, you need to have in mind that the device does not do a full two port measurement. You measure either S11 or S21 at a time. Also, there is a bit of a matching problem when doing S21 measurements. To fix this I put 10 dB pads on both the connectors to get the ringing down. But, once you figure out how to deal with these issues, the unit works great for the price considering it works up to 6.8 GHz.