开云体育

I also ordered from dowjors3236, but, have been unsuccessful in getting a refund.

When I first complained to eBay customer service, they directed me to PayPal because the item's "buyer's protection" is supposed to be handled by the latter. Unfortunately, PayPal's website didn't have a record of the transaction. When I contacted eBay again, they gave me a transaction id for reporting to PayPal's customer service. However, PayPal claimed the transaction id is invalid. After many rounds of to & fro with PayPal customer service (talking to different persons each time), finally, they finally agreed to manually open a dispute for me. That was 2 weeks ago, but I haven't heard from them since.

Another issue is that eBay's deadline for filing a dispute (45 days from purchase) ends before the delivery window.
Chin-Leong, 9W2LC

i installed the Play store on my fairly newish Kindle Fire8
which then let my install the NanoVNA .apk right from the Play store
works a treat
did some repeater work the other day with the setup
really nice to be able to save the graphs as well as the touchstone files
and upload them to google drive

For those that want to experiment

Application note started: /g/nanovna-users/wiki/port-extension-and-de-embedding

Greetings. I use 'screen protectors' on both my 2.8" VNA and my new 'F' model. NO issues.
I started using these a long time ago on my 'smartphone' and have used them on my Icom 7300, 7610, 9700 and Kenwood TS-890 radios, NEVER any issues.
I usually buy the 'tablet' size and cut them to fit. After a couple of tries, it becomes very easy. YES, there is a 'learning curve'.....

ron
N4UE

The BNC calibration standards are not nearly as good as the SMA ones.
There is more stray capacitance and series inductance in BNC because of the
bigger size. I made BNC calibration standards and they work ok, but the
error is definitely much greater above 400 to 500 MHz.

On Sun, Nov 24, 2019 at 1:55 PM Bob Albert via Groups.Io <bob91343=
[email protected]> wrote:

Why not use ordinary BNC hardware with an adapter? Maybe not good all
the way to 900 MHz but fine for casual use.
Bob
On Sunday, November 24, 2019, 10:35:34 AM PST, Daniel Marks <
profdc9@...> wrote:

I was not very satisfied with the quality of the calibration standards I
ordered off of ebay, so I made my own out of PCB edge mount male SMA
connectors as shown here:




The picture is attached. It is simple. One of them is unmodified for the
open, you solder a wire between the center conductor and two PCB edge
mounts for the short, and use two 0805 or 1206 100 ohm resistors, soldering
the resistors from the center pin to the edge mounts.

A pack of 5 of the connectors cost me under $2 on ebaay.

Why not use ordinary BNC hardware with an adapter?? Maybe not good all the way to 900 MHz but fine for casual use.
Bob

I was not very satisfied with the quality of the calibration standards I ordered off of ebay, so I made my own out of PCB edge mount male SMA connectors as shown here:



The picture is attached. It is simple. One of them is unmodified for the open, you solder a wire between the center conductor and two PCB edge mounts for the short, and use two 0805 or 1206 100 ohm resistors, soldering the resistors from the center pin to the edge mounts.

A pack of 5 of the connectors cost me under $2 on ebaay.

I am using Hugen's latest AA FW but have also checked with QRP's latest. I am
under the impression that the format LINEAR is equal to rho, the absolute
value (modulus) of gamma (S11),
and that the formats REAL and IMAG are the real- and imaginary parts of gamma.
What bothers me is that in both Hugen's FW and QRP's FW the sign of format
LINEAR is negative, whereas I expect that an absolute value is positive per
definition. Have I got it wrong? Please help me.

CH0 LINEAR is displayed on device as positive small values with QRP 0.4.3 firmware.
Need to set e.g. REFERENCE POSITION 1 and SCALE/DIV .001x1

I am using Hugen's latest AA FW but have also checked with QRP's latest. I am under the impression that the format LINEAR is equal to rho, the absolute value (modulus) of gamma (S11),
and that the formats REAL and IMAG are the real- and imaginary parts of gamma. What bothers me is that in both Hugen's FW and QRP's FW the sign of format LINEAR is negative, whereas I expect that an absolute value is positive per definition. Have I got it wrong? Please help me.
Regards/Torbjorn

Hi Oristo,

I uploaded it again. You can get it from the same link:

neb

it requires Android 7+

I have not tried, but:
Amazon Fire 7 tablet is on sale for US$30


My understanding that it is based on Android 7+

and can be tweaked to use Play Store apps

and supports USB OTG
.. so may work for Android NanoVNA WebApp

Hi neb -

The software is under development, but if you are interested you can
get it from here:

That URL expired after 1 week.

Thanking everyone for their responses. I was able to resolve the issue by performing a screen calibration using the Touch Cal function in the menu

Hello Norbert,
looks like a bug to me - I'll be sure to check it out and try to get it
fixed :-)

--
Rune / 5Q5R

I placed an order on EBay for a low priced NanoVNA from dowjors3236. He did not have a lot of feedback at the time.
I knew I would get either the VNA or my money back.
Got an email that it was going to shipping and a tracking number.
Kept checking the tracking number and it never said shipped.
When the delivery window ended, I filed with EBay, after leaving negative feedback for vendor.
After I filed, vendor requested EBay open a case.
The next day I received a refund because tracking number was not valid.

Vendor now has a lot of negative feedback, do not know why EBay has not booted him.

At least I got my refund.

Glenn

--
-----------------------------------------------------------------------
Glenn Little ARRL Technical Specialist QCWA LM 28417
Amateur Callsign: WB4UIV wb4uiv@... AMSAT LM 2178
QTH: Goose Creek, SC USA (EM92xx) USSVI LM NRA LM SBE ARRL TAPR
"It is not the class of license that the Amateur holds but the class
of the Amateur that holds the license"

Hi Rune,
the reset reference button is not working for the S11 & S21 LogMag (dB) window (pls see attachments).
If I hit reset reference nothing happens on this window. Reset right on this window works fine.
Is this per design or a bug?

Kind regards
Norbert, DG1KPN

Hello

I just received my NanoVNA -f (4.3 inch display) . When I try to select a menu option
The options disappear. ( No green highlighting unless you use the jog wheel)
Is a stylus needed?

Bob
=============================

Bob,

You need the nanoVNA-F group:

/g/nanovna-f

David
--
SatSignal Software - Quality software for you
Web:
Email: david-taylor@...
Twitter: @gm8arv

Have problem shown up specifically with nanoVNA Saver? I am running Pyton 3.8 and it appears to be working just fine.
-rick

Bob did you remove the plastic protective cover from the screen?

I just mine today too and it's wonderful!

Hello

I just received my NanoVNA -f (4.3 inch display) . When I try to select a menu option
The options disappear. ( No green highlighting unless you use the jog wheel)
Is a stylus needed?

Bob