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clearconfig 1234 did not seem to help

To calibrate I:
Connect open to CH0, OPEN
Connect short to CH0, SHORT
Connect 50 ohms load to CH0, LOAD
Remove 50 ohms load from CH0 and connect to CH1, ISOLN
Connect CH0 to CH1, THRU

I tried both connecting the loads directly to the VNA, and through male-male
cables with female-female adaptors in the ends (then remove one of the
adaptors to perform THRU).

Maybe I did not understand it correctly, but it appears to me that you
are using cables with open ends to connect to the transformers. If this
is the situation, how do you calibrate the nanoVNA?

I have made a set of cables using RG316 with SMA connectors at one end and short wires at the other. I also made a set of open, short, load and through connectors that the wires attach to so I can calibrate the VNA right to the end of the wires.

I know this is not going to work well at high frequencies but for around 10MHz it does seem to work and I have seen a few videos where others have done similar things which gave me the idea to try this.

I think this is similar to your suggested method except I have attached an extra bit of cable and am using my own SOLT connectors rather than the ones which come with the NanoVNA as I can calibrate right at the very ends of the wire.

In reply 11814 I can see the return loss on my cables is around -33dB when CH0 is connected to CH1 at 7MHz and using the supplied cables and through connector (reply 11835) it is around -43dB.

As far as I can tell, every android device would need an OTG adapter or
OTG cable to work with the NanoVNA. That way, the android sees the vna as
an active device and not just as a passive storage device.

As far as I can tell, every android device would need an OTG adapter or
OTG cable to work with the NanoVNA. That way, the android sees the vna as
an active device and not just as a passive storage device.

I got my nanovna in October or November, 2019. For Black Friday I bought
a Samsung Galaxy Tab A 10.1 and wanted to connect it to the nanovna. I had
already gotten OTG adapter cables for other uses, and have connected a USB
mouse and USB keyboard to an older tablet and even to a phone.


Because I've seen postings by people who have had trouble connecting their
android to the nanovna, I thought I might be able to provide some helpful
information. So, here we go.

For use with the new tablet, I bought this package from Amazon:
CHENYANG Ultra Mini DM Micro USB 5pin OTG Adapter Connector for Cell Phone
Tablet & USB Cable & Flash Disk - 5pcs

They are roughly the size of a fingernail and connect to the nanvna end of
the usb cable. Both ends of the adapter fit Micro USB connectors, so
another cable may be added to connect to the USB-C connector on the nanovna.
In July 2018, I had purchased this adapter =
Rankie Micro USB (Male) to USB 2.0 (Female) Adapter, On-The-Go (OTG)
Convertor Cable, 3-Pack (Black)
which may be another possibility, depending on your stock of USB cables on
hand.

Pasting my old urls/descriptions from my Amazon Orders page don't seem to
show up as links, but the text descriptions should enable a person to find
a suitable adapter. Most seem to come in packages of several. Adapter
cables came 2 or 3 to a pack, and the tiny adapters were 5 of them for a
little over $4 - with free shipping! If you're in a big enough city, with
big, well-stocked computer stores, you might be able to find a local source
for a cable or adapter. But it might be a long search! I'm sure they
would also be on ebay, but Amazon is more convenient for me, plus it has
the reviews which I generally find are very useful.

So - I hope this might help new NanoVNA users who want to connect their
vna to an android device. It sure can help when you're outdoors in bright
daylight!

Doug, K8RFT

Tuning the “CB” antenna will be EXACTLY like any other antenna, just
follow the docs in the wiki for the rest of them. There’s definitely a
learning curve though, the nice smart folks on this site make it all sound
soooo easy, but that’s because they know what they are doing and understand
the theory’s behind all this stuff. I’m still trying to figure out who
this guy “Smith Chart” is!!! ;-)))

--
Regards,
Chris

Yes, same here. Stuck at airport. That's why I posted.
It points to the fact that no flights are being permitted between
USA and China. For previous orders from China, it usually is
only at the airport for a day or two, then shows landed in destination
country.

Oh well. Maybe we will get them in late summer...

Neal

Thank you very much for your suggestions - I really appreciate them and have learnt a lot from reading about the various ideas people have offered and from doing my experiments.

I have just re-done the CH0 to CH1 return loss test using a different set of cables and have got better results, the image is attached. Using these cables the return loss is -53dB at 1MHz and -33dB at 30MHz so pretty close to those shown by Roger and Arie.

I need to use my other cables though for testing as these have non-sma ends on that allow me to attach to the transformers. By non-sma ends I mean short wires but I assume (hopefully correctly) that at low frequencies (7Mhz) this should not make too much difference.

My next step is to attach my new transformers to the NE602 and see how the output looks.

On Thu, Mar 19, 2020 at 09:57 AM, David Shrum wrote:

... for now the only thing I'm interested in is the SWR of the antenna I'm
checking. ..
========================================================

David,
? ? A lot of ham's only want to use the NanoVNA the same way they use a MJF
analyzer and don't care about the other functions, at least initially.

? The following Web translator link by a Japanese ham does a good job of
going through the steps of getting rid of unnecessary display traces and
setting up CH0 to use the NanoVNA as an antenna analyzer.




or try:



and use Microsoft or Google Translate.


- Herb