开云体育

Actually, a 'mode' byte, similar to the features byte/word I had suggested would be good for that.It could reflect the live status of the device, showing its current mode.Both could work together.Sounds like this little device might become more versatile (and robust) over time - but we're going to need that '303 uP installed real soon...

On Sat, Oct 12, 2019 at 05:49 PM, Oristo wrote:

there is some corruption of the data as received by the application

Have you tried inserting a USB 2.0 hub between nanoVNA and Linux PC?

Thanks Oristo, I tried that but no difference.

Thanks Rune, you were correct. Upgraded original GEN111 02.08.19 firmware to edy555 0.2.3 07.10.19 and problem fixed.

Nanovna# 1.03 now runs on 32 bit Win7 guest on 64 bit Linux Mint 19.2 host using virtualbox 6.

The recent Mod3 variant also works. It can capture a screenshot direct from the device.

73
Nick

On Fri, Oct 25, 2019 at 10:43 AM, Rune Broberg wrote:

at least early versions of the firmware (which still
exist "out there") included commands in the "help" output which did not
exist

This is impossible. "help" command implemented in the ChibiOS shell module and returns command list from array of registered commands. If "help" command returns command name, then this command is registered, so it is exists. If some command is missing from "help" command, it means that this command is not registered, so it doesn't exists.

On Thu, 24 Oct 2019 at 20:01, Bear Albrecht <W5VZB.NM@...> wrote:

Who might know the specs on the nylon screws that hold the nanoVNAs
together?
Guessing M2.5, phillips fillister head.

Mine is M2.5. I know that because I have one of those multiple length
standoff/nut kits from Adafruit in that size, and the nylon standoffs
fit. I needed longer standoffs because I soldered header pins onto the
interface / DFU mode side of the board and those pins were too tall
for the stock standoffs.

--buck

I guess if I have to go to soem hard to access space to take measurements I
would not be happy to rely on pause button. I would like to make snapshot that
survives even turning device off. Also, when I am there I might need to make
several measurements, for example to check several antennas or cables, or
simply to check cable and antenna independently.

Since most folks also have a smartphone, it seems more practical IMO
to add such complexity by e.g. Android app using USB OTG.

Member cho45 already an Android app for nanoVNA:



This "might" be a "simple" feature to add..

It looks like it's significantly faster (13 milliseconds) if using
scipy.signal.convolve - even though that adds another dependency to the
application, I'm considering allowing it this time.

--
Rune / 5Q5R

I don't know what "convolve" does,
but I assume it's something quite complicated?

"convolve" is a rolling sum.



For this special case of convolving with constant one,
it can be speeded by dropping the oldest value and adding the newest to the sum
for all ones in e.g. self.step

This is AKA 1-D box filter or summed area table

I guess if I have to go to soem hard to access space to take measurements I would not be happy to rely on pause button. I would like to make snapshot that survives even turning device off. Also, when I am there I might need to make several measurements, for example to check several antennas or cables, or simply to chech cable and antenna independently.

That said, I agree it is better than no means to save measurement :) This is so low priced device that it is quite acceptable.

Eric,
thank you very much for the diff files. There's one small issue though -
speed.

Looking at the TDR response with 2**16 FFT points, and 101 data points, I
get the following:
IFFT 6 milliseconds
"convolve" operation 3634 milliseconds

I don't know what "convolve" does, but I assume it's something quite
complicated?

Is there a better (= faster) way of doing this calculation?

--
Rune / 5Q5R

Hi YT9TP, Pedja -

Is it possible to take a sweep & capture with the standalone Nano VNA then
connect to NanoVNA Saver at a later stage and download the previous sweep
parameters for display ?

That would require NanoVNA to have additional memory,

How many stored sweep captures are necessary?
Using "PAUSE" keeps the most recent sweep until power off.
QRP fixed a bug so that data can be retrieved by USB reconnection,
provided that "resume" is not sent before.

On 24.10.2019. 15:47, Martin via Groups.Io wrote:

Hi All,
Is it possible to take a sweep & capture with the standalone Nano VNA then connect to NanoVNA Saver at a later stage and download the previous sweep parameters for display ?

That would require NanoVNA to have additional memory, probably microSD card or so.

It is not possible with current NanoVNA but might happen in some new hardware version.

And it would be great to have that.


--
73,

YT9TP, Pedja

I'll just note, that at least early versions of the firmware (which still
exist "out there") included commands in the "help" output which did not
exist.

Yes, it seems to me that testing for '?' in return from such commands
is the easy way to test for support.

Commands that simply change behavior with firmware version are problematic,
unless they can be provoked to return '?' for some different argument count or values.

Commands (such as "trace") which ignore arguments and change responses
independent of anything controlled by shell commands would be most problematic.

but it might confuse the user if nothing happens
if they try to do a further sweep of something else?

Thanks to noise, it seems highly unlikely that "data"
would return identical values to repeated commands

$ nt data > paused.txt
$ nt data | diff - paused.txt

$ nt data | diff - paused.txt | wc
0 0 0
$ nt resume
$ nt data | diff - paused.txt | wc
204 608 5653

Currently, when connecting to a device, the first thing the application
does is to sweep whatever range the device is set to. If this works with
your pause function, then that's fine - excellent in fact - but it might
confuse the user if nothing happens if they try to do a further sweep of
something else?

If nanoVNA is paused when USB is connected, then it will return
values to sweep command without exiting PAUSE

$ nt sweep
10000 1500000000 101

The default NanoVNA-Saver hardware code also calls the "resume" command
after sweeping, in order to ensure that the device does not appear locked up.
This would remove the data the user had saved, which might be a problem?

Sending "resume" indeed causes user data to be replaced by automatic sweeps,
so capturing results by first sending "data" is wanted before sending "resume".

Hi Sam,
Nooelec are authorized by edy555, the original creator of the NanoVNA, to
resell the device:

I believe they are USA based and stocked.

--
Rune / 5Q5R

QRP,
is there a way to see for the app if the sweeping is paused or not?

Currently, when connecting to a device, the first thing the application
does is to sweep whatever range the device is set to. If this works with
your pause function, then that's fine - excellent in fact - but it might
confuse the user if nothing happens if they try to do a further sweep of
something else?

The default NanoVNA-Saver hardware code also calls the "resume" command
after sweeping, in order to ensure that the device does not appear locked
up. This would remove the data the user had saved, which might be a problem?

I'm very happy to see that we might finally get my initial use case for
this application - the "Saver" part - implemented :D

--
Rune / 5Q5R

Hi QRP,
I'll just note, that at least early versions of the firmware (which still
exist "out there") included commands in the "help" output which did not
exist. I believe the "scan" command started like that? So I have, at least
for now, completely discounted the "help" command as a way of determining
supported features. I could be persuaded to do otherwise for
individual features, though :-)

--
Rune / 5Q5R

Hi Sam,
I purchased this one:


I have been happy. Works well, is shielded, came with calibration kit &
cables.

It is more expensive than others but I received it in about 5 days and
Amazon would take it back if there was a problem.

Hope this helps.

Marco -KG5PRT

Sam,

If you don't mind paying a bit more for the device you can go through Amazon to get one. I purchased mine through Amazon and it came within 2 days. Shipping was free because I have a prime membership. It has the cal kit, battery, shielding, two cables and an SMA female to female barrel which was not very good. The vendor (AURSINC, $72..99) is out of stock until October 31 according to the Amazon web site.

If it is listed as being available through the prime membership, they have US stock and can ship it to you. Here is one example I see at the moment for $79.97..

Amazon claims you could get it by Sunday, October 27.

Here is another one showing a price of $61.99 that claims to be deliverable by Monday, October 28.



Please be aware I have not purchased from either of these vendors. Read the ad carefully to make sure that what you want is included.

Good luck.

73
--
Bryan, WA5VAH

Does anyone have a recommendation for a seller for a good quality NanoVNA with cables and OSL?

I ordered one a while back and the dealer is no longer listed on eBay and I have not received it as of today.

Thank you,

Sam
W3OHM
LeCroyOwnersGroup Owner and Moderator on groups.io