Many 50 Ohm loads are made with two 100 Ohm smd resistors in parallel. I've seen many loads fail after intensive use, all the sudden they are 100 Ohm when connected. Unconnected 50 Ohm. We solved it by using male/female adapters, so the loads will never be disconnected. By the way, there are adapter without internal thread (male side), you just push them over a female connector. We use the loads in the final product test of RFID readers.
But for calibration of a VNA, I'd use a good quality load without an adapter. Currently I use the cal kit supplied by sdr-kits, based on Rosenberger connectors. They also sell kits based on Amphenol connectors, these loads are junk and will become 100R soon. Never had a problem with the Rosenberger load. Also the load from minicircuits is excellent (ANNEQ-50X+)
Op 21-3-2020 om 05:46 schreef Hern¨¢n Freschi:
toggle quoted message
Show quoted text
I found the problem. My 50 ohm load was OPEN. I don't know if it can be opened to solder something inside. But tapping it on the table made it work again.
So weird.
|
Hi Tor,Tank you so much!Vy 73 de Gianni IW4ARDInviato da smartphone Samsung Galaxy. -------- Messaggio originale --------Da: Torbj?rn Toreson <torbjorn.toreson@...> Data: 20/03/20 23:47 (GMT+01:00) A: [email protected] Oggetto: Re: [nanovna-users] Battery for nanoVNA Hello Gianni,For my 2,8¡± NanoVNA I bought a 3,7 V 750 mAh LiPo battery from Electrokit. It is larger than the original battery but thin enough to be placed sticking over some of the components. As you can see on the pictures I have washers to give some extra room. Works very good. Product number at Electrokit is 41016063, the price was about 10 Euro (about the same in USD). The reason to exchange the original battery was that it started swelling and that it was nice to have a larger capacity.73/ Torbjorn, SM6AYM> 19 mars 2020 kl. 19:32 skrev Gianni Matteini <iw4ard@...>:> > Hi to all,> I have buy nanoVNA without battery, anyone can help me for buy battery on Europe.> Vy 73 Gianni, IW4ARD> > >
|
It looks like the hex file in the zip collection is the new version, but the bin file is the 0.7.0 version!
--John Gord
toggle quoted message
Show quoted text
On Fri, Mar 20, 2020 at 07:56 PM, hwalker wrote:
edy555 has released firmware version 0.7.1-20200321 for the NanoVNA. No major
changes from version 0.7.0:
Contributions from @DiSlord
- shrink flash size
- faster sweep
- added color command
Added lever operation for the electrical delay (electrical delay value can
be changed using jog switch after setting with keyboard)
edy555's firmware releases are only for the 2.8" NanoVNA's but usually make it
to future firmware releases for the NanoVNA-H4 and NanoVNA-F. He does not
release his firmware in DFU format, so on windows you have to convert the HEX
firmware file to DFU format using the STM Dfu file-manger app.
- Herb
|
I found the problem. My 50 ohm load was OPEN. I don't know if it can be opened to solder something inside. But tapping it on the table made it work again.
So weird.
|
edy555 has released firmware version 0.7.1-20200321 for the NanoVNA. No major changes from version 0.7.0:
Contributions from @DiSlord
- shrink flash size
- faster sweep
- added color command
Added lever operation for the electrical delay (electrical delay value can be changed using jog switch after setting with keyboard)
edy555's firmware releases are only for the 2.8" NanoVNA's but usually make it to future firmware releases for the NanoVNA-H4 and NanoVNA-F. He does not release his firmware in DFU format, so on windows you have to convert the HEX firmware file to DFU format using the STM Dfu file-manger app.
- Herb
|
Hello Gianni,
For my 2,8¡± NanoVNA I bought a 3,7 V 750 mAh LiPo battery from Electrokit. It is larger than the original battery but thin enough to be placed sticking over some of the components. As you can see on the pictures I have washers to give some extra room. Works very good. Product number at Electrokit is 41016063, the price was about 10 Euro (about the same in USD). The reason to exchange the original battery was that it started swelling and that it was nice to have a larger capacity.
73/ Torbjorn, SM6AYM
toggle quoted message
Show quoted text
19 mars 2020 kl. 19:32 skrev Gianni Matteini <iw4ard@...>:
Hi to all,
I have buy nanoVNA without battery, anyone can help me for buy battery on Europe.
Vy 73 Gianni, IW4ARD
|
Re: H4 large display size: Fonts??
Perfect, thank you
--
Regards,
Chris
|
Hi all,
Mine just left China... " CNNKGD,China, International item has left originating country and is en route to Canada ".
I have few antenna to construct before summer... hope I get it in time.
Have a good one all.
Richard.
|
|
|
|
|
Alex,
I have seen this before when I forget to reset before calibration. Press RESET twice to clear the current cal tables and then recalibrate.
Roger
|
There have been some reports on here of new NanoVNA-H4 devices having similar issues. Some have found loosening the case screws takes pressure off the LCD screen and then it works.
Rather than repeat what has been posted before I suggest you search here for the posts on this topic.
Roger
|
On 3/20/20 8:12 AM, dave wrote: hi whats the best software to run for my nano vna i use both linux and windows 10 ???? NanoVNA-Saver.? It's awesome, and runs on both Linux and Windwoes.
|
Is there a way to do a system reset. You know - hold something down, stand on one foot while smiling?
|
The only thing that makes the menu bar appear of disappear is if I touch the smith chart area. The jog wheel does nothing at all. I even tried using the q tip and it works the same as using my finger or the clip that came with it.
|
I hadn't calibrated my nanovna for a while and today have discovered it acting strangely. Before when I finished calibration the open read on the far right of the smith chart, the short on the far left and, the load dead center. Today after multiple cal tries on different frequencies my open reads only about 1/3 to halfway to the right and the swr reads only about 3.3.
I put the load on an vom and it reads about 51 ohms. Any ideas?
Battery charge meter is about 1/3 above empty. Can a low battery cause this?
|
Use the jog wheel to select CONFIG in the menue, then calibrate the touchscreen.It's a resistive touch surface so you'll need something like a Qtip.
toggle quoted message
Show quoted text
On Friday, March 20, 2020, 12:33:39 p.m. GMT-4, david@... <david@...> wrote:
Hi all.
I just got a new NanoVNA-H4 from GigaParts. It wasn't sealed so that is a red flag to me.? However, everything is there.? When I turn it on I see the intro screen for about 10 seconds and then it changes to a smith chart.? When I touch it a menu comes up on the right but I cannot select anything.? I can press on the smith chart and it goes away or reappears but that is all I can seem to do.? Any ideas? I have tried my finger and the pick they sent.
Thanks. David
|
Hi all.
I just got a new NanoVNA-H4 from GigaParts. It wasn't sealed so that is a red flag to me. However, everything is there. When I turn it on I see the intro screen for about 10 seconds and then it changes to a smith chart. When I touch it a menu comes up on the right but I cannot select anything. I can press on the smith chart and it goes away or reappears but that is all I can seem to do. Any ideas? I have tried my finger and the pick they sent.
Thanks. David
|
Hi Robin,
You have 4 options here:
1. buy the newest 3.5GHz unit
2. use your unit with either a tablet, phone or PC via USB
3. check to see if a solder pin on the LCD's ribbon cable got cracked and resolder
??? if the ribbon cable pulled off the LCD end, you're going to need to buy a new display
4. get a new 3.2" display anyway - there is a how-to file in the forum showing how to upgrade and in the meantime, do option 2
Good luck!
toggle quoted message
Show quoted text
On Friday, March 20, 2020, 11:15:42 a.m. GMT-4, Robin Midgett <k4idc@...> wrote:
While tuning an antenna this evening using my NanoVNA, I dropped it onto
concrete. It landed on the corner nearest the multi-function selector
switch. Now, the display lights up, but there's nothing on the display. The
two blue LEDs behave normally; the one nearest the multi-function switch
changes in intensity as I move the switch, but there's no displayed
data...just the back light. The display doesn't appear cracked or
damaged...just devoid of information.
Using the NanoVNA connected to a PC with NanoVNA software, it works as
it should.
Might any of you have suggestions as how to attempt a repair of the data
display?
Thanks,
Robin Midgett K4IDC
|
See this groups software Wiki page, /g/nanovna-users/wiki/home#Software . NanoVNA-saver will run natively in both Windows 10 and Linux. Most of the other software run natively in Windows 10 but require Virtual Box to run under Linux. - Herb
|
Chris K2STP
Roger Need
Jim Allyn - N7JA