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You are right. But frankly speaking I do not understand why the spurious do not influence the test results. I am lacking the theory behind.

Here are some plots/data capture.

All good questions and point. Thanks. I shall post my measurement plots. I did both data capture as well as photo shot of the VNA as it looks a bit better on the VNA screen as opposed to the data

No, EU1KY is quite a bit different in any case, you have a limited resolution bandwidth even if it is not apparent as a physical filter circuit. although I think there must be a lowpass filter after

He is implementing a narrow bandwidth filter in the DSP to remove artifacts of the square wave. It is the same procedure used by the FA-VA5 and EU-1KY antenna analyzers. Otherwise the square wave

I may be wrong, but: * is nanoVNA not derived from the EU1KY antenna analyzer? * in which case, mixers basically mix down to DC (no IF) - bandwidth limited by RC networks into ADCs with 5.5 MHz gain

in this instrument with a very simple schematics (although I don't have it in front of me and vaguely remember the general picture of it) I don't remember seeing any type of variable filter or filter

Excellent point. Is there a tag between the analyzer sweep range and its resolution BW? I should do a cal over a reasonable narrow frequency range and see if this helps the situation. Otherwise it may

it's not that surprising, I think, considering that the RBW (or IF BW) of this instrument is definitely not narrow enough to give you the resolution required for like a 1KHz or perhaps even 5KHz span.

So ... I have played a little more ... Thanks to Larry for listing the serial commands ... I can now command my nanoVNA from ubnuntu using them .. and after a play and putting putty on the same

I started looking at some narrow band mechanical filters. The measurement was challenged to look at a 500 Hz wide 455 kHz filter. I will double check if the limits are 101 data points/interpolation or

I use an old blackberry 800mA charger. Grab the datasheet for the IP5303 charger chip that's used for more info. https://datasheet.lcsc.com/szlcsc/INJOINIC-IP5303_C181693.pdf (Chinese) 1.2A Charging

Thanks, I was wondering about the charger . It will at least charge a 800ma Thanks

Frank - do a search though the forum and you'll find all kinds of useful info that others have already supplied... Have a look at my posts & photos - I stuck an old Motorola 800mAH cellphone batt on

Does anyone know how big a battery in mAh (charging wise) the unit can handle? Frank

Is anyone interested in an extended back cover for the NanoVNA? I designed and printed a sample it has a 6mm deep "pocket" that is 71mm X 40mm. Should be big enough to double sided tape a bigger

I just ordered 1 from Banggood preorder, I hope this is the correct one to make sure Huegen gets paid for his work

Several discussions with my ham colleague Gary, N3GO and wrestling in a quite area, I believe I have ONE approach that works well and is consistent with proper results. The main items to note: Only

You know, of course, that the signal out is a square wave. According to the schematic, the Si5351 feeds the output directly through the resistor bridge..

I believe that's exactly how they have extended the range of this instrument to 900MHz: by using the harmonics. otherwise Si5351 is only rated up to 200-300MHz. This is the same principle used in