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Thanks, Jim. I'll read the analysis. I didn't realize the ADC was 16 bits. That's a lot. Now I feel even less forgiving about the observed performance. I don't understand why the possible

The measurements are made by integrating over 1 millisecond, after a I/Q conversion to 5kHz. It's a 16 bit ADC, but the noise floor isn't quite that good, and there's system noise too. I started a

1 in 5000 is actually pretty good. That's 0.02% - I doubt the load is known that accurately over that bandwidth. Similarly, the reactance of the load is probably not zero. 0.1 ohms at 50 kHz is

That's an interesting idea, Dave. The LF spike is indeed at 60 kHz. However, N6LF is in Oregon. I would not expect WWVB to be that strong there. When connecting the VNA to a ground probe, occasionally

The spike at the extreme left could be WWVB at 60 kHz. Have no idea what the spike at 1.8 MHz might be. Dave - W?LEV -- Dave - W?LEV

N6LF has been trying to calibrate his NanoVNA-H4 through a wideband balun for common-mode current suppression when measuring an open wire line ground probe. He has had perplexing results. As a test he

Anyone have a part number? Usually, the data sheet will show S21 and S11.

The boards use three terminal ceramic filters for Bandpass. (Really only two terminal, but can be installed without regard to “polarity”. They are actually ceramic resonators and sell for

It occurs to me (after looking at some pictures of the test board)) that they might have just put something like a 10.7 MHz IF filter on the board. Here's an example of such a filter, f

I couldn't find a schematic for the test board, so I don't know what the BPF looks like. Span is just the size of the sweep - either you set start and stop, or set center and span.

Do you set the frequency range say from 20 Mhz to 50 Mhz, and set the centre frequency to 30 Mhz, and then sweep the frequency to get the graph? What about SPAN and RBW (band width) - what do you set

That would likely be the S11 magnitude - in the passband, the filter lets the RF through, so it sees the 50 ohms on the other side, so refl

Greetings, The open, Short, Load calibration is fine for single port measurement. However,?there are two additional calibrations to be completed when you intend to perform two port?measurements.

I received the RF Demo kit for NanoVNA. The cables are indeed fiddly to attach on the pcb board, but I am getting used to it. Just hope that it will last for some long time rather than get mangled,

Hi Chris, 1. Have you ensured USB OTG is turned on? https://youtu.be/2qxr2NkAohY 2. Have you tried connecting a USB storage device and seeing if it is detected properly? To confirm it's usb data pins

Is there a particular reason you're upgrading the firmware? I'd see if the unit will make the measurements you want with the existing firmware. Hook it up to your PC and use one of the PC

Steve, If the defuse demo installation lasted for so long, you may need help to you someone on the spot. You can view the process description from a different perspective on my website

Hi all you experts! Just trying to use my older nanoVNA-H- ver. 0.2.3-1- for the first time and thought I'd update the FW before I got going. I'm not a computer guy, but believe, using the Absolute

Hi, John. Oppo A52 v11 Chris VK5SA

Thanks, Gyula - Chris