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Wow, Thanks Dave.
I did not realize I could do that. Just like verifying calibration on the Nano without connecting to the computer.

Steven/kc3dow

QUOTE: I don't see any way to verify calibration with Saver but what I do
is setup the frequencies that I want to check before doing calibration.
..........................................................................................................................

You are correct in setting up your frequency span before doing the cal. in
Saver.

However, it is easy to check cal. once it is run in Saver. Use the same
standards you used for cal. and sweep each one at a time. The short should
show a short - extreme left of the Smith Chart. The open should show an
open - extreme right of the smith Chart. The 50-ohm standard should be
bullseye in the center of the Smith Chart. It's that simple.

Dave - W?LEV

On Wed, Aug 2, 2023 at 7:53?PM Steven KC3DOW via groups.io <treasurebox7762=
[email protected]> wrote:

Hi Barry,
Not a 'J' pole. It is a Diamond X-50A. My previous antenna was a 'J' pole
but did not reach an area that I needed to reach.
This Diamond does the job but I am trying to train myself to use the
NanoVNA-H and learn Saver when I ran into the problem. I was trying to
check swr to see if it was within specs.
By the way. I did the calibration correctly and by the book and also did
the verification which was successful.
I don't see any way to verify calibration with Saver but what I do is
setup the frequencies that I want to check before doing calibration.

Thanks for your help,
Steven/kc3dow

--

*Dave - W?LEV*


--
Dave - W?LEV

If the antenna is supported by a metal mast, make sure the lower discone
elements (those closest to the mast) are connected to the coax OUTER
SHIELD, and the top elements to the coax INNER. If the connections are
reversed, the mast interferes with the antenna impedance.

Regards,
Joe L

On Tue, Aug 1, 2023 at 12:26 MarcoFI <marcofigroupsio@...> wrote:

Hi Team,

I try to measure VSWR of the following antenna:



NanoVNA is calibrated to antenna side of RG58. I had to use N-F/SMA-M +
SMA-F/SMA-F adapters in front of SOL kit, but tried to subtract it with
edelay.

On the product page someone wrote "Swr on 2m is 1.5 to 1.7.1 on 446 it's
1.0.1". I can't seem to get even close, something wrong with me setup. Any
suggestions what am I missing?

Best Regards,
MarcoFI





--

__Joe Leizerowicz
6424 34 Avenue NW, Calgary, AB T3B 1N1
403-604-7791

Hi Barry,
Not a 'J' pole. It is a Diamond X-50A. My previous antenna was a 'J' pole but did not reach an area that I needed to reach.
This Diamond does the job but I am trying to train myself to use the NanoVNA-H and learn Saver when I ran into the problem. I was trying to check swr to see if it was within specs.
By the way. I did the calibration correctly and by the book and also did the verification which was successful.
I don't see any way to verify calibration with Saver but what I do is setup the frequencies that I want to check before doing calibration.

Thanks for your help,
Steven/kc3dow

one has to consider the environment, not discussed prior in this thread. If
there were any metal or other electrically conductive material near the
antenna when tested that could be a possible cause for the difference in
measurement data and that which is published.
*Clyde K. Spencer*



On Wed, Aug 2, 2023 at 11:09?AM Jim via groups.io <teotwaki=
[email protected]> wrote:

This antenna is related to what antenna design literature calls a
“产颈肠辞苍颈肠补濒“

- - Biconical antennas have dipole characteristics. The double cone
elements structure contributes to their wider bandwidth. The antenna
becomes more broadband as the cone angle increases. - -

Search on that name for design and results discussions

Jim

This antenna is related to what antenna design literature calls a “产颈肠辞苍颈肠补濒“

- - Biconical antennas have dipole characteristics. The double cone elements structure contributes to their wider bandwidth. The antenna becomes more broadband as the cone angle increases. - -

Search on that name for design and results discussions

Jim

Fully configured tinyPFA for sale at Eleshop.


--
For more info on the tinyPFA go to
Erik, PD0EK

Thanks for your comments. I bought the antenna from local radio store that has a good reputation and it's a shame if they sell crap as it's starting to look like.

I tried to model the antenna in 4nec2 and its output curve looks a bit similar to NanoVNA measurement. NanoVNA shows higher SWR though, not sure why?

Based on both results it seems that this antenna could not be used for TX at least not in the advertised lower 130-175 MHz range and therefor I think I own 16 pieces of nice stainless steel skewers.

Oh…. I just saw you said a VHF antenna.

I’m going to guess —-

Any chance this VHF antenna is a J-Pole?

If so, when measuring SWR with your Nano VNA, rub your hand up/down the coax near the VNA jack and see if the SWR changes as you move your hand over a 1 meter length.

If the SWR changes, we know the problem.
Current on the outside of the coax.

barry
k3eui

Take a look at the published gain specifications by MoonRacker of their CB
antennas. You'll rapidly convince yourself anything MoonRacker publishes
for their antennas is total rubbish. They are not a reputable supplier for
the amateur radio world, RX only and/or RX/TX.

Dave - W?LEV

--
Dave - W?LEV

You might be missing the fact that the antenna isn't what it is cracked up to be. Your SWR "someone wrote" is malarki... There isn't any manufacture data (not that I would believe it if there was...)
So... depending how it is wired it may just in fact be a simple dipole rather than a discone...

Hi Team,

I try to measure VSWR of the following antenna:


NanoVNA is calibrated to antenna side of RG58. I had to use N-F/SMA-M + SMA-F/SMA-F adapters in front of SOL kit, but tried to subtract it with edelay.

On the product page someone wrote "Swr on 2m is 1.5 to 1.7.1 on 446 it's 1.0.1". I can't seem to get even close, something wrong with me setup. Any suggestions what am I missing?

Best Regards,
MarcoFI

That is very odd indeed, Steven.

Try this:
Connect a 50 ohm dummy load and do an SWR sweep when Nano VNA is not on SAVER.
Take a look at SWR, reflection coefficient, return loss, and Smith Chart.

Then do the same tests with the same dummy load with Nano VNA SAVER software running.
The graphs should be identical

If not, I suspect a “calibration” error when you were doing the Nano SAVE calibrations.

If they are identical with a dummy load - then there is no problem with SAVER.
Then I would check the coax for something “odd”.

Let us know if the dummy load produces a SWR of 1:1 across the band you are testing.

BTW - what antenna ? and what frequencies?

If this is your “end fed” then I would look for RFI leaking back on the outside shield of the coax.
That is often an issue with “end-fed, one-half wave” 130 ft wires with a 49:1 UNUN.

Put some kind of “choke” in the feed line.
The outside shield may be acting like your “counterpoise” inadvertently.

give me a call when you figure it out
k3euibarry@...

barry

Thanks everyone, that worked.

You may find these two videos from W0QE interesting:





He discusses three different methods to test components, and why you might want to use each one for components of various values. I used to use his fixturing methods well above the frequencies at which you will be testing doorknob capacitors.

Hi David,

I just checked the gitHub site, and the latest version 0.6.1, as of ~10 hours ago, only has three assets listed for the latest revision all of which appear to be Linux-based. However, if you scroll down the page a bit to the previous version, Version 0.5.5, under the 05-March block titled ‘Core is spinning’, and go down to the bottom of that block, you should see the word “Assets” just below the ‘Contributors’ section. Click on “Assets”, and that should open another listing from which you can download either the 32-bit or 64-bit Windows executables for Version 0.5.5.

With any luck, someone will compile the Windows executables for the latest Version 0.6.1. Good luck. 73

Ken -- WB?OCV

From: Paul Braun
Sent: Monday, July 31, 2023 06:02 PM
To: [email protected]
Subject: Re: [nanovna-users] releases

Hmm. There are notes about the Windows version having issues and they were also wondering if Windows is no longer supported.


Paul Braun WD9GCO
Anchor, Amateur Radio Newsline
Certified Music Junkie

"Never follow anyone. Be your own hero." -- Neil Peart

"Music washes from the soul the dust of everyday life." -- Berthold Auerbach

"The Fountain of Youth is a state of mind" -- The Ides of March, "Age Before Beauty"

"Deep inside we're all the same." -- Dennis DeYoung/Styx

On Jul 31, 2023, at 16:41, David Rodriguez Martin <dr8297@...> wrote:

?Hi Team,

I have been trying to download a windows installer from . The windows installer have been changed to text rather than links and I am wondering if the nanovna has stopped supporting the windows release.
David, M0KGE

Hmm. There are notes about the Windows version having issues and they were also wondering if Windows is no longer supported.


Paul Braun WD9GCO
Anchor, Amateur Radio Newsline
Certified Music Junkie

Hi Team,

I have been trying to download a windows installer from . The windows installer have been changed to text rather than links and I am wondering if the nanovna has stopped supporting the windows release.
David, M0KGE

Are you measuring a vertical ground plane antenna?
When you connect the nano to the computer, the ground on the cable makes
your computer case and all attached to it part of the local ground plane,
which is much larger than the nano itself. This can cause significant
variations at vhf and above if you are not careful in providing a ground
plane for the antenna in your measurement setup. The cable also provides a
path for electrical noise between the computer and nano. Ferrites on the
USB cable can help with this part of the problem.

On Mon, Jul 31, 2023, 2:49 PM Steven KC3DOW via groups.io <treasurebox7762=
[email protected]> wrote:

I am having different SWR readings between my NanoVNA-H (Not connected to
the computer) and NanoVNA saver versions 3.9 and 3.10, NanoVNA-H version
1.0.45

I have followed directions carefully when setting up and verified
calibration when the Nano is not connected to the computer.
I don’t believe there is a way to verify calibration when in Nano saver.

This problem appears regardless whether I am using version 3.9 or 3.10 of
saver.

An example would be the following:

When Nano is not connected to the computer the SWR for a given VHF
frequency would be 1.5.
When connected to Saver it may be 3.4 in saver version 3.9 doing the
measurements correctly.
and 4.2 in version 3.10.

When I am thinking about it this is not possible because the SWR is being
read off of the Nano unit to the saver.

I have used the manuals for SWR as well as several You Tube videos to
verify that I am the measurements correctly.

Thank You,
Steven/kc3dow

You can buy calibration standards or caps from Ebay with text on them. O, S or L