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there is no memory on the board to store results.

Just tested, with previous firmware version (nanoVNA_900_ch_20190802.dfu) it works ok with 5 kHz span. I tried even 10 Hz span and it works ok. But the new firmware version

I am finally understanding the concept of calibrations and saving the settings/range in the nanoVNA. But I am wondering if there is any way to save results from out in the field and then

How does one calculate the uncertainties of an out of calibration VNA and calibration kit bought on ebay? In an ideal world everyone would do as you ask. But the nanoVNA has made it possible for

I've seen at least one firmware version where the minimum attainable step size was 100Hz. I don't exactly know why, but your findings fit my observations as well. -- Rune

I catch some strange bug in the latest firmware. I tried to get better resolution around 26.996500 MHz to see crystal resonance. Span 10 kHz works ok. But when I trying to setup span=9 kHz or 5 kHz or

I tried the S21 method. Connected the 2 center pins (CH0 and CH1) to the choke ends (coax shield on both ends). -20dB at the frequency of interest is a decent common mode attenuation. -30dB is good.

Yes, that's all you need. I ran a similar case with a single strand of #22 AWG with and without the addition of the lossy core material. Although very nice particularly for looking at common mode

Yes, I am familiar with the "other" PN systems. Thanks for the clarification. I assumed this was test set limited, however, just to be sure. Regards, Alan

A poor mans test jig for checking if these cheap chinese chokes do anything. Two SMA female chassis connectors with the ground pins soldered together and a short wire connecting the center pins. The

Can you show the measurement? preferably the smith chart of another VNA doing the CH0 measurement.

It makes a lot of sense. From 0-300MHz you get the 2mA drive fundamental and its harmonics From 300-900MHz you get8mA drive with fundamentals from 100-300MHz and its harmonics from 300-900MHz So

Bruce, There were a couple of accompanying articles to the previous one that go into further detail.

It seems that CH0 output also has impedance about 40 Ohm. So, it's better to use two 10 dB attenuators. One on the CH0 and the second on CH1.

The source may be DC-DC convertor. Try to disconnect external power from NanoVNA, is it still present?

I think noise may come from DC-DC converter used in battery charger. Because there is noticeable higher noise when external power supply is connected and this noise is not come through cable. It is

I opened the nanoVNA and connected the line in of a good USB audio device to the reference SA612. But as I did not dare to do two connections the unbalanced signal had a lot of noise. And there were

Hello, Allow us, please, to point out that to be possible to the slightest a comparison between measurements regarding nanovna and/or vna, these measurements should be accompanied by an estimation of

does only scalar measurements

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