I’ve got one as well. I use the NanoVNA2 on the bench because you can interface it with your PC and use nanovna-saver to control the device, save plots, use multiple calibrations, etc. The device itself doesn’t have a great screen nor does it usually come with a case so it’s hard to use in standalone mode.
Here’s the Amazon link although it looks like this particular one is out of stock. It’s an open source design so multiple manufacturers offer it. Just look for the V2 with the 50KHz -3GHz bandwidth. https://www.amazon.com/gp/product/B089DJXMX3
In the “field” I use the N1201SA one because it’s a lot easier to read and control when outside but you can’t have multiple calibrations or save anything.
Thank you gtj0.
My field is my apartment, as I have strictly indoor installation (including the antenna). Thanks to my Building Management’s strict rules.
Your results with the ProStick are closer to what I expected.
I’ll have to see if I can find another ProStick Plus to see if my example is representative.
With any test set like a VNA, you’ll find a collection of in-line attenuators invaluable.
They are great for protecting external circuits as well as providing a high confidence you are getting a linear response.
Pretty sure @geckoVN was more or less eluding that attenuation should be used when reflection testing on your VNA from the noise source or post amplification so you don’t blow the front end of your testing equipment out. Attenuation between your antenna and radio stabbed into the Pi just makes things mighty quiet
Pictures of that setup will be confusing to some I think.
The purpose of posting these photos here was to show that attenuators are sometimes neede for a test setup. I did not mention the actual purpose of inserting attenuators between antenna and ProStick to avoid confusion, as it did not relate to tests using a VNA.
However as you have asked for an explanation, here is the post where full detail of why the attenuators were inserted in antenna circuit is given. It was meant to show that ProSticPlus gets saturated without an external filter, and performance drops to near zero, but if attenuaters are added, these dampen the interfering signals and performance shoots up even without external filter.
Just remember though that if you are trying to measure S11 you can not use an in line attenuator without affecting your measurement. For instance a 10dB attenuator will present a 20dB return loss even with a short or open circuit on its output. You will be measuring your attenuator not the load presented by the device under test.
True, but the same goes for any measurement - the effect of the attenuator must be taken into account.
The benefit is your test set will survive to do battle another day.
Blow the front end and no amount of compensation will give you a reading!
