开云体育

Hi Andy,
it does. Down to 1Hz, I believe?

--
Rune / 5Q5R

On Mon, 11 Nov 2019 at 15:21, Andy via Groups.Io <punkbiscuit=
[email protected]> wrote:

Mine appears to be 100Hz steps.
Test method, use receiver, listen to span set for 300Hz and I can hear 3
distinct tones.
Does the newer firmware use lower steps ?

73 de Andy

Hello Hans-Peter,
you're right: The algorithm assumes that the first -3dB point it finds is
the -3dB point of the filter. I'm not certain what's a good and generic way
to avoid this to allow filters to have that much ripple?

Suggestions?

--
Rune / 5Q5R

All nanoVNA use the internal SI5351 outside the formal supported spec. e.g. upto 300MHz in fundamental mode. Above 300MHz it switches to harmonics mode (till 900 MHz) and even further harmonics modes above 900MHz
Some do work till 300MHz in fundamental mode , others less good
The latest firmware has the "threshold" command to reduce the maximum frequency for fundamental mode.
Setting (as an example) this the threshold to 280MHz will have the nanoVNA switch to harmonics mode above 280MHz. You may not even notice this.

--
Erik, PD0EK

Please see the attached pictures. The one in the case I am calling the good one the other one has issues.

1. Spur on display around 300MHz. This appears to change and amplitude but is always there.
2. Spurious data on displayed in the smith chart green trace. This comes and goes.

Any ideas?

Sam
W3OHM

Hello Rune,

First of all many thanks for this great software!
Maybe you can watch the bandwidth calculation again.
A ripple on a bandpass does not capture the filter width correctly.
In the attachment a comparative measurement.

Best regards

Hans-Peter Prast, DL2KHP

F-2 might be a nice instrument to wait for... hopefully w/full 4 port setup extended f range and the larger display.

Really I think there are solutions for the current display issue including the android and laptop/PC software.

I for one would like to see options to hack in a larger screen. Even one
the size of the screen used on the HP/Agilent/Keysight HP8753D. It would be
great to be able to turn one of these into a bench instrument. Maybe a DVI
compatible output or standard VGA. After being used to a HP8753 screen size
it's hard to go back and having the response time of the built in display
is a must.

The smaller ones are great for field work but even those could use a larger
screen. Something like an option to use one of the ones used with the
Raspberry Pi like below would be wonderful.
These displays are very inexpensive:





Sam Reaves
ARS W3OHM
Owner and Moderator of:
LeCroy Owners Group on Groups.io (Current and Future Group)

Mine appears to be 100Hz steps.
Test method, use receiver, listen to span set for 300Hz and I can hear 3 distinct tones.
Does the newer firmware use lower steps ?

73 de Andy

I've been trying to get this working - keeps coming back and saying the ID doesn't match even though it does.?

Since the last commit to this was several years ago - there is most likely some bugs introduced by newer version of Android.
It would be really nice if CHO45 could integrate this into his webUSB app
...Larry

On Monday, November 11, 2019, 8:13:50 a.m. GMT-5, Oristo <ormpoa@...> wrote:

> Unfortunately I do not have another computer to do that

I found this GitHub project for DFU installation by Android app

I have heard that there are frequency rounding errors on some versions,
but I cannot determine if I have that issue because
I'm not sure how to set it up for a sweep, and advice greatfully received.

If you are using original firmware and touchscreen control, then this map shows
where to set START and STOP frequencies (under STIMULUS)


These settings can be saved, either under CAL or RECALL / SAVE

I ordered a set of attenuators on Ebay.
Logarithmic and linear... I'm not at home right now but when I get back, I'll try it on the computer.

Thanks everyone for the info.

I have what appears to be a two trace version, 900Mhz, and to be honest it appears to be satisfactory.

No crashes etc.

Although there is one thing that I have not yet played with, and that is how to sweep a small signal range for xtal filters.

I have heard that there are frequency rounding errors on some versions, but I cannot determine if I have that issue because
I'm not sure how to set it up for a sweep, and advice greatfully received.

Not too fussed about a battery indicator, since I think it already has one, if I turn it on and there's no display then battery = dead ;-)

I quite like the idea of an auto find lowest SWR etc function, that could be useful, but no deal breaker, I just zoom in a bit more.

So, I guess that I may have aplay at some time,but I'm not in a rush.

73 de Andy

Google searches don't find specific details about the V2 design

Gabriel is the layout designer and RF engineer
/g/nanovna-users/message/3420
/g/nanovna-users/message/3984
/g/nanovna-users/message/4092
/g/nanovna-users/message/6544

Unfortunately I do not have another computer to do that

I found this GitHub project for DFU installation by Android app

The github page you refer to is from Henrik Forsten, so it is not "mostly a copy of this nice design", it is the very same design!

Op 11-11-2019 om 13:19 schreef erik@...:

Hi Gabriel,

What you are saying sounds fantastic. That is the kind of project that I would like to be a part of. I don't have a need to see the designs early. I'll be patient, and get involved when the product releases, and after I buy one. You said that the firmware is already on GitHub. Can you provide a link? Who is the designer for that? Google searches don't find specific details about the V2 design, just people talking about what they think it will be.

Thanks,

Dave

Trying one more time to add the attachments.

Hi Hugen,

Thanks for joining the conversation. I appreciate all of the work that you have put into this design, and for your efforts to turn it into an actual product. Your work seems to have been the trigger that made the NanoVNA so popular this year, and why I now own a NanoVNA. I love it. It’s just what I needed.

I understand the things that you said in your post, but I don’t agree with everything that you said. I do understand your reluctance to release the board files, but eventually that hurts your community more than the cloners. It is greatly appreciated that you share your schematics, but the photos of the PCA on your GitHub page are wrong. It seems that you do this on purpose to misdirect the cloners, but the only people that are really confused by it are the ones who want to support you.

It may have taken the cloners a little while to copy your designs, but it seems that they have finally gotten there. I’ll attach photos. This is what they do, and they are fast at it. In fact, the clone from Amazon was at v3.2, while the official Nooelec board was still v3.1. You say that you could make your PCB better to distinguish, but the performance between the clone and Nooelec board was identical. My point is that the cloners will always eventually catch up. It’s what they do. Trying to misdirect them by not providing accurate photos of your PCAs doesn’t really slow them down.

The people in this group however rely on you to be open with what you are doing so that they can collaborate on the designs with you. That is why many of them are here. That is what makes this group a community.

I would suggest that you try a different tactic than misdirection to fight the cloners. Use authenticity and this community. These are two things the cloners don’t have. I would suggest updating your GitHub page to provide accurate photos of the PCA, remove the complaints about cloning, and then do better marketing. Have people from the group write some articles for RTL-SDR, ARRL, etc. Have people on this group spread the word at Ham meetings, and so on. Focus on the things the cloners can’t copy.

That’s all I have to say. I hope you don’t take offense to my comments.

How to overcome the need to turn off/on every time we plug the USB cable to PC?

Use QRP firmware:

Based on my own trivial experiments, metal enclosure for worse unshielded clone
makes things somewhat worse above 600MHz.
Otherwise, limitations appear to be from internal crosstalk and e.g. mixers' nonlinearity.