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Sure, I'll try that. I'll try an xtal in its shunt mode, so just a S11 measurement. Then in series mode in which case I should pick up both a S11 and S21 set of values. I assume you measured the xtal

Thanks for info, George. Thats what I was looking for.

Sorry, but gave you wrong reference date for QEX article. It is titled "DG5MK IV Meter, An Accurate Antenna Analyzer" by Michael Knitter in the May, 2017 issue of QEX.

Now try a single crystal, closely scanned/calibrated, near resonant frequency point. It won't be matched to 50 ohms but will still give you a narrow curve. I tried a crystal at 27 MHz and it looked

"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." If the system is linear, the harmonics can be separated

BTW the images attached are so compressed that often it is very hard to read any text. Can this be modified by the moderator of the group?

Just by curiosity I made a phase noise measurement of the output signal. For comparison the overlay in the picture is my 10MHz rubidium standard which shows the measurement limits of my system.

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