开云体育

once again

--
*** If you are not part of the solution, then you are the problem. ( ) ***

Linked to DiSlord's description, I enclose some pictures of how it works:

--
*** If you are not part of the solution, then you are the problem. ( ) ***

Photo showing shield

I have just purchased a Nano VNA, and, not being entirely sure of its provenance I'm wondering whether or not it is a cheap clone. The shielding is one-piece, but has cutouts that seem to indicate that there is a wall between TX and RX sections.

But, rather than figuring out good -v- bad from the appearance of the construction, it seems to me that it should be possible to see the effect in the performance.

So, my question really is: how does one tell by looking at the traces? It seems to me that, calibration notwithstanding, the limitations of the device should be apparent with some simple tests.

With a 50 ohm load on the CH1 port, the noise seems to be in the region of about 50dB down even at the 900MHz end - which seems to be usable to me. But than I have nothing to compare it with.

So what can one expect? And what other simple tests (without external equipment) can one make using the device itself?

Steve

Now all work correctly
Screenshots, and s1p or s2p correctly stored on SD card

A lot of thanks Gyula Molnar for help test and fix bugs from this firmware

PS this version also contain all my last fixes as on H4

SD Card slot on old PCB can see in this post, if solder it and install this firmware now possible store screenshots and S1P or S2P files on it.
Some limits. Only FAT12/FAT16/FAT32 support (exFAT not supported). RTC clock not run while power off (hardware limits, need install external quartz and add software support). Only short filenames.
Most limits comes from small flash size in H version CPU.

/g/nanovna-users/message/14154

Just curious if this unit has the shields?
I'm thinking it does, but want to verify.
Mikek

Thanks for all the answers to the partnumber, I already ordered the one mentioned by @DiSlord from lcsc.

The flash card was freshly formatted with fat32 and is blank but writable.
Ok I mean 1-2 seconds. I waited a minute, but frost, not asking what to name.

This is precisely why I look for good, sound write-ups that are correct to
best practices in engineering and high frequency - no snake oil. I read
each reference before I hit 'send'. Yes, many are quite technical and may
require a bit more searching on the part of the reader, but they are sound
and correct to engineering and physics. Again, no gain.....no pain.....
Isn't that what learning is all about?

Dave - W?LEV

--
*Dave - W?LEV*
*Just Let Darwin Work*

Write should take ~1-2 seconds, try search problem

On flash card exist created file?

When I tap the BW: 1000Hz 101p location, nothing happens after that ... just the graph freezes. How long should I wait now? If the USB is on it, I will remove it and draw again.
--

An image of the SD card socket (Molex 503398)

--

Maybe a small animated progress bar or count-down timer could be added?



On Sat, 6 Jun 2020 at 4:08 PM, Gyula Molnar<gyula.ha3hz@...> wrote: Hi DiSlord,

I have had the SD socket in it for a week so I was able to test.
What I have experienced is that when I want to save a screen image, it recognizes the sd card and the structure seems to hang. Or I didn't wait long enough and then you'll tell me. There was no window for what name to save. The same happens in the menu when saving .s1p under SD Card. It’s like it freezes or I should see what I don’t know because the drawing freezes and apparently nothing happens.
I hope this helps you move on.

Gyula HA3HZ

--
*** If you are not part of the solution, then you are the problem. ( ) ***

On Sat, Jun 6, 2020 at 01:08 PM, Gyula Molnar wrote:

Hi DiSlord,

I have had the SD socket in it for a week so I was able to test.
What I have experienced is that when I want to save a screen image, it
recognizes the sd card and the structure seems to hang. Or I didn't wait long
enough and then you'll tell me. There was no window for what name to save. The
same happens in the menu when saving .s1p under SD Card. It’s like it
freezes or I should see what I don’t know because the drawing freezes and
apparently nothing happens.
I hope this helps you move on.

Gyula HA3HZ

--
*** If you are not part of the solution, then you are the problem. (
) ***

Possibly i not correct vork vs short filenames (not test it)? as i see SD card work, answer, problem only in work vs lib or screen read.
Here support long names like at H4 (now in most cases code some except support exFat), now i hope it work

I scrounged one from an old cellphone but there are different footprints so you'll need to see if a cheap multi format card reader might also have the correct type of socket.?



On Sat, 6 Jun 2020 at 2:33 PM, Christos SV1EIA via groups.io<sv1eia@...> wrote: That looks great!

Got a H4 here and I see that there is space/footprint for a mini/micro? SD.
Does anyone has a partnumber on what connector can we place there?

Ordered on June 2nd and received today (6th). Love the bigger screen compared to my 2.8 inch unit.

Hank W6IR

Hi DiSlord,

I have had the SD socket in it for a week so I was able to test.
What I have experienced is that when I want to save a screen image, it recognizes the sd card and the structure seems to hang. Or I didn't wait long enough and then you'll tell me. There was no window for what name to save. The same happens in the menu when saving .s1p under SD Card. It’s like it freezes or I should see what I don’t know because the drawing freezes and apparently nothing happens.
I hope this helps you move on.

Gyula HA3HZ

--
*** If you are not part of the solution, then you are the problem. ( ) ***

On Sat, Jun 6, 2020 at 07:00 AM, Dana Whitlow wrote:

Another problem is that much material is written so poorly that it fails
to answer the real question satisfactorily and without ambiguities.

Cite specific examples; I may address them.

On Sat, Jun 6, 2020 at 11:33 AM, Christos SV1EIA wrote:

That looks great!

Got a H4 here and I see that there is space/footprint for a mini/micro? SD.
Does anyone has a partnumber on what connector can we place there?

See this topic for more info
/g/nanovna-users/topic/nanovna_firmvare_compiled_by/73181877

For H4 version

Possible search for alternative, but select option:

microSD? Memory Card "connector&Ejector"

option for easy insert and remove card (use Push In，Roll out option)

That looks great!

Got a H4 here and I see that there is space/footprint for a mini/micro? SD.
Does anyone has a partnumber on what connector can we place there?