开云体育

Hi I've recently taken the plunge and purchased a nanoVNA. It's the credit card sized version and it had internal shields fitted. It works much better than I was expecting but I did notice an issue at 6.7MHz on mine.
When measuring anything with a reflection coefficient very close to 1 it shows a glitch in the response at about 6.7MHz.

For example, if I measure a 10k ohm 0805 chip resistor, the plot for Rp looks pretty good across 50kHz to 50MHz and it shows an Rp quite close to the expected 10k ohm resistance when the data is dumped out of the nanovna and post processed to show Rp. However, at 6.7MHz the resistance narrowly spikes up to maybe 13k ohm. When I measure an inductor across the same range I also get a narrow spike in Q at 6.7MHz. I think this is in the hardware as this 6.7MHz glitch seems to be very stubborn. Is my nanovna faulty or is this a limitation of the hardware?

Ed Jones wrote:

I want to purchase a VNA from Hugen's site but none of my credit or debit
cards seem to work on Alibaba. Is there a trick to placing an order from
the States? Is this site blocked by default by payment processors? Sorry
for the off-topic question.

What is the exact failure message given?


Have you established an Ali Baba "cloud" login and added your payment method (credit card) to the profile there?


--
Wes Will
N9KDY

Hans, many thanks!
Very fine method!
Merry Christmas and Happy New Year!
73! Andy, UA3RAW

Nobody on ebay advertising v3.4 H units yet, guess they want to get rid of "old" stock first.

I read that the new ones will have a sticker on the back stating v3.4 board inside. I can imagine the printers of some smart boy cloners chugging away mass printing those same stickers as we speak and putting them on all their remaining v3.3 stock.

I want to purchase a VNA from Hugen's site but none of my credit or debit
cards seem to work on Alibaba. Is there a trick to placing an order from
the States? Is this site blocked by default by payment processors? Sorry
for the off-topic question.

--
Ed Jones - K8MEJ - Lewis Center, Ohio U.S.A

"When I was sufficiently recovered to be permitted to take nourishment,
I felt the most extraordinary desire for a glass of Guinness...I am
confident that it contributed more than anything else to my recovery."
- written by a wounded officer after Battle of Waterloo, 1815

Hi Boo,

the display seems some old lcd from phones or something, the polarisation of the display is for portrait use. If you look at it in portrait mode you will notice the difference. In landscape the viewing angle is narrow.

Maybe some dev can write menu option to rotate it, some libraries for displays have easy options to rotate.

Regards, ersoz

Check capacitor C1 for leakage I had several of them fail in different units. They fail from short to leaking / act as a resistor. They are 10Uf non polar and I use a panasonic 100V version to replace them.the panasonic is a little larger but can be installed. The capacitor in question is directly parallel to the Battery leads and located close to the battery connection point on the board. Everytime one failed, the unit exhibits the same type of behavior you describing,

On Sun, Dec 29, 2019 at 05:27 AM, John wrote:

" … I was afraid to mention the NanoVNA at a Keysight Technologies training session for fear of immediate eviction and missing out on the free lunch buffet and swag bag and took the Device from my knapsack and hid it under a flowerpot after wiping any fingerprints off it and retrieved it 1 hour after everyone left. …"
================================================================================

John,
Nice satirical article to get the week started off on a lighter note. I guess its no coincidence that the Canadian Broadcasting Corporation (CBC) was first to introduce Monty Python's Flying Circus to North America.

- Herb

Birdman,

My friend is a subscriber to QEX and "lent" me his actual magazine or as we
say in Canada "a copy"

This all took place in a coffee shop and I made sure we recorded the
transaction on video

No Canadian laws were broken as I read the article with immense pleasure
and then "gave back" to him his "copy" of the magazine

What will continue is this "mystery" of the article and its contents.

I am sure the CB community is having a field day over this situation and
has rallied its supporters to buy up every issue of QEX possible to ensure
the Ham community remains in the the dark over this specific article
(review). The information contained in the magazine has been identified as
a "literary threat" and "high risk".

Please enjoy our Malaysian friends offering their PHD commentary on other
VNA devices and were approached to revise their article but claimed that
there are now so many fake versions that any tests would be invalid.



The Jan 2020 issue of QRP Quarterly by QRP ARCI will be publishing a user
review on the NanoVNA and I have already reviewed it for publication so
stay tuned.

I want to say I bought the official modified version through the offered
link not the eBay version

73s
John VE3IPS

I was afraid to mention the NanoVNA at a Keysight Technologies training
session for fear of immediate eviction and missing out on the free lunch
buffet and swag bag and took the Device from my knapsack and hid it under a
flowerpot after wiping any fingerprints off it and retrieved it 1 hour
after everyone left.







--
Sent with a Palm Pilot. Ve3ips.wordpress.com
Radio: it's not just a hobby, it's a way of life
All content is personal and confidential

Hi i cant see the ports listed with this or connect,im running it as admin on vin 7 sp1,any ideas?

On Sun, Dec 29, 2019 at 02:41 AM, Gabriel Tenma White wrote:

btw we just merged in all recent changes from edy555's firmware branch, so we have all the new features like TDR, marker search, marker delta, group delay,
etc. ;)
===================================================================================
Gabriel,
If you also merged edy555's python branch ( ) it would help those of us who have used that class library to develop solutions, quickly get up to speed with your NanoVNA V2 and subsequent versions.

- Herb

Hi ersoz,

Normal display is Landscape, 320 pixels wide x 240 high.
Your picture shows Portrait 240 pixels wide x 320 high, with an egg shaped Smith Chart

Change of orientation would involve software rework, perhaps unlikely.

Regards, Bob GM4CID

Hi,

i like m nanovna, but unfortunately the display is not the best one. The original alignment of the display is portrait, but using it in landscape looks not so good.

Is it possible to rotate the display in 90° like on the photo?

Hi Marcel,

If I understand it, searching for "NanoVNA doesn't want to start" in forum discussions may be a solution. It's a good idea to read these and it might help. As far as I remember, there was mention of increasing the capacitance of the electrolytic capacitor.
I note that you refer to the white Gekko as ttrftech as an official supplier.
Remember, ttrftech is named after the original idea host (@ edy555). It was the business of the clone manufacturers and their dealers to steal this.

Use the Search Button.
I wish you a successful search and repair.

73, Gyula HA3HZ

btw we just merged in all recent changes from edy555's firmware branch, so we have all the new features like TDR, marker search, marker delta, group delay, etc. ;)

If you can see the images I posted you'll see it runs the same UI as the Nano ;) And it's compatible with the most widely used Nano software, nanovna-saver.
The STM32 we are using is of the same specs as the next generation -H (the F303).

Hadn't heard from you in a while

I have been pursuing other interests and muted several topics and hashtags here.
You, Larry, Erik, Alan and others do fine; I should add more "like"s.

I was just wondering what scheme he might use
to keep backwards compatibility with the current software.

The USB shell `sweep` command already supports `[points]`...?

no text (console) commands, but instead there is a registers and FIFO
interface... easy to implement on a FPGA based VNA,

If compatible with neither nanoVNA (nor, sadly, VWNA) software and lacking STM32 support,
then substantially as unrelated to this group as any other low cost VNA.

It's 201 points per save location, 5 save locations total.

The command interface is *not* compatible with the original Nano, but I already have a working patch for nanovna-saver which I will upstream once the protocol is solidified.

There is a description of the new command interface here:
You can see an example of how to talk to the HW here:

Long story short there are no text (console) commands, but instead there is a registers and FIFO interface.
It is still a USB serial device like before, but you manipulate the operation of the VNA by sending a set of bytes to write and read device registers, and measured data is transferred by issuing a READ FIFO command. The reason it's designed like this is because the protocol is intended to be easy to implement on a FPGA based VNA, which we have plans for in the future. "Real" VNAs can do tens of sweeps per second which we intend to reach with V3, but we can't get there if we kept the old text command interface.

On Sat, Dec 28, 2019 at 09:11 PM, Gabriel Tenma White wrote:

"... Finally got 201 point sweep working.
You can now configure arbitrary number of sweep points between 2 and 201 (on-screen)…."
===================================================================
Gabriel,
Is that a maximum of 201 sweep points for all 5 save locations (total = 1005 max)? Will your shell commands be backwards compatible with the NanoVNA or will you use a different CLI?

- Herb