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So the question is, what precautions can be taken to protect the NanoVNA ? Prayer is not an option ;-) 73 de Andy

The CH0 input of the nanoVNA is basically an attenuator connecting to a SA612 mixer without any additional protection.

editing the .submodules file: - replace the 3rd line with "url = https://github.com/edy555/ChibiOS.git" - add a new line to the end of the file Finally type "git submodule sync", and then "git

Thank you very much for your post, John. Posts like yours certainly give me motivation to continue working on the application, even when I find issues that are difficult to solve in an elegant manner.

Hi David. I've updated the post with instructions, on the opposing side of the SMA connectors CH0 and CH1, there are two pins on the PCB labelled VDD and BOOT0. They need to be shorted with the

This sentence “Flash by setting the device to DFU boot, either in software or by short of pins, then:” could usefully be expanded. I don’t know how to do either Dave -- Dr. David Kirkby, Kirkby

Hi Reg, Ohan made a guide. I'm not certain the SSH keys are required, but it's all there: https://zs1sci.com/blog/NanoVNA%20Build%20Source/ -- Rune / 5Q5R [email protected]> wrote:

Greetings Dr. David, Thank you for flagging my less than clear and possibly misleading post! I did not intend to infer that my DIY 50 Ohm load has the quality of a 53 dB return loss instrumentation

and left comments to the savants. Now, though, with this 0.0.10 release, I just have to convey a massive "thank you" on behalf of all of us lesser users, ham radio operators particularly. We hams now

When a VNA is connected to an antenna (often they are outdoors) there are some potential issues with electrostatic discharge (ESD.) In dry areas of the world ESD can be an issue even when working with

Reginald and Dr. Dave Since you both completely missed the point of my post I must assume the fault for that is mine in the presentation. My post did not focus on what parameters were being measured

The wikipedia definition of "return loss" is rather absurd. If you have a *perfect* match and *no* power is reflected, the "return loss" is infinite. Of course it *is* wikipedia. I'm not about to try

FWIW a bit of TDR porn on "finger tight" vs torqued. I think it should be noted that in this example, the ringing is at over 5 GHz, so it really doesn't matter for the current version of the nanoVNA.

I measured an SMA load to have a return loss of *56 dB* to 1.3 GHz. I am fairly confident that the return loss is at least *37 dB*. The equipment I used was an HP 8753ES VNA with a cheap (only

When I am testing amplifiers, using one of my network analyzers, I normally start at -30 dBm output from the signal source, into the device under test. You don't to come anywhere close to saturation,

Tks for mentioning that Dave. I forgot to add that besides the amplifier gain and max input, the 1 dB compression point should be taken into account when determining the system budget.

Whilst his methods of making open short and loads is not had, his verification procedure looks seriously flawed to me. Unless I am mistaken, he performs a calibration using his standards, then

Whilst an LNA can probably take 0 dBm without damage, it would be driven well beyond its linear region. I just took as quick example, one of the Minicircuit amplifiers I have here

Kurt, After your comment about not being impressed with the HP 50 ohm loads, I checked their return loss from 50k-900MHz and you are correct that their high frequency return loss is not impressive. At

All my low noise RF preamps have a maximum input of 0 dbm and can handle the maximum output power of the nanoVNA without an attenuator. You have to know what your system budget is and choose your