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I have a similar issue with my SAA2 on windows 7. It's a driver issue I think. Runs ok on windows 10. Not sure how to fix it.

I always calibrate to the interface of the "vna/jig/cable combination" with the DUT because that interface is whatever circuitry the DUT is connected to will be seen as.
E.g. if you are testing an antenna mounted on a tower and are interested in the impedance of the feed point of the antenna then calibrate the vna and included feeder to the point the feeder connects to the antenna on the tower.
Similarly it is also important to carefully consider your reference point for calibration when sweeping/ tuning filters; in this case a set of cavities used in multiplexing.
On Sat, 5 Nov 2022 at 9:59, Brent DeWitt<bdewitt@...> wrote: Single turn. Tolerance is a good note, but my readings are consistently less than half the specified value.? Unfortunately, Fair-Rite is the only company who has written anything about how they measure their product, and they made the comment that other companies may do it differently.

I still think my "errors" may come from the way I calibrate.? For an S11 calibration into a fixture, should the fixture be included in the OSL cal, or performed at the input to the fixture.? For an S21 cal, should the fixture be included at all, or only the connecting cables.

Hopefully, I'll stumble on to an answer that agrees with the vendor one of these days!

Thanks again for your input, Jim!

Greetings, Just as an FYI: There is a great deal of downloadable generic reference material from?Rhode & Schwarz relating to all things VNA.

The following events on the usb port my nanovna is attached to is causing the program to not connect:

Faulting application name: nanovna-saver.exe, version: 0.0.0.0, time stamp: 0x632416e2
Faulting module name: Qt5Core.dll, version: 5.15.2.0, time stamp: 0x5fa4dd3b
Exception code: 0xc0000409

The program error is that the "attempting to use a port that is not open"

Nanovna-saver runs, but when attempting to connect to the com port the usb to the device, the previous event takes place and the program terminates.

Any help in resolving this would be appreciated.

The following events on the usb-port my nanovna is attached to is causing the program to not connect:

Faulting application name: nanovna-saver.exe, version: 0.0.0.0, time stamp: 0x632416e2
Faulting module name: Qt5Core.dll, version: 5.15.2.0, time stamp: 0x5fa4dd3b
Exception code: 0xc0000409

The program error is that the "attempting to use a port that is not open"

Any help in resolving this would be appreciated.

I have a Copper Mountain VNA in my lab at work, so I will probably try to get some generic advice from them next week, without mentioning that it's really for use with a nanoVNA at home.

Single turn. Tolerance is a good note, but my readings are consistently less than half the specified value. Unfortunately, Fair-Rite is the only company who has written anything about how they measure their product, and they made the comment that other companies may do it differently.

I still think my "errors" may come from the way I calibrate. For an S11 calibration into a fixture, should the fixture be included in the OSL cal, or performed at the input to the fixture. For an S21 cal, should the fixture be included at all, or only the connecting cables.

Hopefully, I'll stumble on to an answer that agrees with the vendor one of these days!

Thanks again for your input, Jim!

I agree with Jim Lux. Holding the VNA in your hand is both simple and probably the most representative of the performance with an HT. In the olden days, the German VDE 0871 testing standard used a salt water column with a plate on top for testing hand-held devices. Jim's suggestion lets you simulate you!

On 11/4/22 8:04 AM, Brent DeWitt wrote:

The parts I'm currently playing with are all Laird ( formerly Steward) 28 alloy, with the Z peaking in the 100-200 MHz region. The data I'm referencing is from their data sheets.
I'll read through Jim's paper. Thanks!

What test fixture are you using? 1 or a few turns through the core?

Note that these things have about 20% tolerance with respect to the datasheet values, too.

The parts I'm currently playing with are all Laird ( formerly Steward) 28 alloy, with the Z peaking in the 100-200 MHz region. The data I'm referencing is from their data sheets.
I'll read through Jim's paper. Thanks!

Brent AB1LF

What ferrites and where's the reference for them.
Jim K9YC has done some fairly extensive choke testing.

Mike W9MDB

I having fits trying to measure lossy "soft" ferrites against the manufacturers curves. Over the range 1 to 300 MHz, I'm not even getting close, looking at either S11 into a short or S21. I've tried a few home-brew fixtures, and they all yield a Z which is much lower than the published data, so I'm thinking it is my fixturing and calibration that are doing me in.

For those that have been successful:
- Do you perform you OSL cal at the input port to the fixture, or the far side?
- Is your preferred method S11 into a short, S11 into 50 ohms, or S21?

Just to set the level of conversation; I'm quite comfortable driving around a Smith Chart and have been involved in RF for a very long time, so feel free to pick me apart!

On 11/2/22 12:20, N2MS wrote:

InfoAge did accept my Radio and Electronic Data Books, Equipment Manuals and Electronic perodicals. I donated it in the spring of this year.
The person I worked with is Ray Chase. Is business card shows www.InfoAge.org his email address is radio862@...
Most of my Data Books were for semiconductor and integrated circuit devices. Among the periodicals accepted were my collection Popular Communications magazines.
They are selective on hardware donations but were actively looking for RADAR equipment.

My guess, the ISEC folks but radar would be very appropriate for InfoAge & Camp Evans.
A lot of work was done there from WWII until the 80's (maybe the 90's). The makerspace
used to be called IXR - Institute for Exploratory Research. We still have the sign.

If you have any documentation I would check with them before trashing it.

Oh, so it was InfoAge - cool. Don't worry they're probably still around here. :-)
We're very careful about tossing things. You never know what's appropriate.

--
Linux Home Automation Neil Cherry kd2zrq@...
Main site
My HA Blog
Author of: Linux Smart Homes For Dummies KD2ZRQ

On Tue, Nov 1, 2022 at 04:36 PM, WB2UAQ wrote:

What if a number of insulated turns are wrapped
around the tower

Well, that would have not only magnetic coupling but considerable capacitive coupling also with the wire wrapped around the tower. The resonant frequency of the magnetic and capacitive coupling could be a problem. You could minimize the capacitive coupling by standing the wire off some distance - an inch or several inches? - from the tower.

Wish I had a structure to test this on.

Try it on a street light pole or something. A stop sign post or a flag pole.

the Tacoma Narrows (wasn't that Galloping Gurdy which mechanically
resonated?).

Sure was! Have you seen the video of that?

... So as to stay on the topic of Network Analyzers one piece of equipment Info-Age accepted was my General Radio 916 RF Bridge.

Mike N2MS

InfoAge did accept my Radio and Electronic Data Books, Equipment Manuals and Electronic perodicals. I donated it in the spring of this year.

The person I worked with is Ray Chase. Is business card shows www.InfoAge.org his email address is radio862@...

Most of my Data Books were for semiconductor and integrated circuit devices. Among the periodicals accepted were my collection Popular Communications magazines.

They are selective on hardware donations but were actively looking for RADAR equipment.

If you have any documentation I would check with them before trashing it.

Mike N2MS

On 10/22/22 12:18, N2MS wrote:

... Fortunately InfoAge Museum in Wall NJ accepts technical documentation. ...

Not InfoAge but more likely The Vintage Computer Federation (VCF - museum) or
NJARC (Antique Radio museum). I don't think we (Computer Deconstruction Lab -
CDL - Makerspace) got them. InfoAge manages the camp (Camp Evans) and the museums
are responsible for they're piece of the world. :-)

CDL has a NanoVNA-V2 for our digital ham equipment. NJARC has the boat anchors,
meant respectfully. ISEC has the 20m dish. Can you use the NanoVNA on a 20m
dish?

--
Linux Home Automation Neil Cherry kd2zrq@...
Main site
My HA Blog
Author of: Linux Smart Homes For Dummies KD2ZRQ

In the 70's I worked at a transmitting station that had about 10 three wire 2 to 30 MHz "rhombic" field antennae fed with 600 ohm open wire feeders.On a whim one day I backed up my Celica fitted with a FT301D and home brew multi-band antenna mounted on the rear of the car, to the vertical section of the feeder of one of the field antenna.? As I approached the feeder, the whip coupled with the antenna as witnessed by the significant increase in a received signal was listening to on the 10 meter band.? The field antennae were not connected to any transmitters that day so all feeders were open at the feed point.
This idea stemmed from a previous day walking along the boom of a Collins rotatable LPA (at 120 ft height) with a 27 MHz hand held used as a local engineering circuit.? At that time it was impossible to communicate with the ground due to the overpowering signals being received from Asian sources.I figured this was due to the coupling between the hand held and the RLPA - comms was OK at ground level.
I was at the maximum coupling point at about half a meter from the feeder.
So, I wonder if a vertical antenna parallel coupled to the tower would work?
If it is possible to electrically connect a wire at the top of the tower and drop it down parallel to the tower thus forming a folded monopole and connecting the bottom of the wire to the VNA with the reference (earth) of the? VNA connected to the base of the tower would also work - you'd be able to identify resonance, just not necessarily at 50 ohms.
Dino. ..? VK4BN (ex VK3IL)
On Wed, 2 Nov 2022 at 9:59, Jim Lux<jimlux@...> wrote: On 11/1/22 4:36 PM, WB2UAQ wrote:

Jim Allyn, I don't have a tower to test this idea.? I read the Notes on measuring tower resonances that you posted where Rudy couples to the tower with a rectangular loop.? What if a number of insulated turns are wrapped around the tower (tighter coupling than with a loop standing parallel to the tower) and the impedance looking into the loop is measured?? When the tower structure resonates the impedance should show a drop when energy is sucked out of the nanovna.? I am thinking this will happen if the tower is grounded or not.? ? Wish I had a structure to test this on.? \

I don't know that you want to wrap the coils *around* the tower.? You
want them magnetically coupled - which is sort of challenging, since
you'd normally have a magnetic core, the tower is "one turn", and your
test coil is multiple turns.

If you have a rectangular loop next to the tower, but "sticking out",
the field from the closer wire couples more than the field from the
farther wire, so you get some coupling (as an "air core transformer")
much like some magnetic loop antennas do.

I would think, too, that you could capacitively couple

On 11/1/22 4:36 PM, WB2UAQ wrote:

Jim Allyn, I don't have a tower to test this idea. I read the Notes on measuring tower resonances that you posted where Rudy couples to the tower with a rectangular loop. What if a number of insulated turns are wrapped around the tower (tighter coupling than with a loop standing parallel to the tower) and the impedance looking into the loop is measured? When the tower structure resonates the impedance should show a drop when energy is sucked out of the nanovna. I am thinking this will happen if the tower is grounded or not. Wish I had a structure to test this on. \

I don't know that you want to wrap the coils *around* the tower. You want them magnetically coupled - which is sort of challenging, since you'd normally have a magnetic core, the tower is "one turn", and your test coil is multiple turns.

If you have a rectangular loop next to the tower, but "sticking out", the field from the closer wire couples more than the field from the farther wire, so you get some coupling (as an "air core transformer") much like some magnetic loop antennas do.

I would think, too, that you could capacitively couple

Jim Allyn, I don't have a tower to test this idea. I read the Notes on measuring tower resonances that you posted where Rudy couples to the tower with a rectangular loop. What if a number of insulated turns are wrapped around the tower (tighter coupling than with a loop standing parallel to the tower) and the impedance looking into the loop is measured? When the tower structure resonates the impedance should show a drop when energy is sucked out of the nanovna. I am thinking this will happen if the tower is grounded or not. Wish I had a structure to test this on. Maybe the resonant frequency of other structures could be measured the same way. How about the Golden Gate or the Tacoma Narrows (wasn't that Galloping Gurdy which mechanically resonated?).