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I have lost your initial message, but if this is an -H4, isnthe MS/SI option ser correctly?

That can change when flashing.

--
Sent from my Android device with K-9 Mail. Please excuse my brevity.

Bryan,

What was your original firmware version? Have you tried re-flashing back to
that version? This would eliminate hardware concerns and focus solely on
firmware. I noticed there are 10 issues flagged on version 1.2.40 which
gives me pause. I also noticed that a new version number of 1.2.42 has been
assigned for a future update.

Tony AC9QY

On Sun, Feb 9, 2025 at 9:51?AM Bryan Curl via groups.io <bc3910=
[email protected]> wrote:

COULD IT BE?

There are three ranges noted on the back label. 50k-300MHz, 300MHz-900MHz,
and 0.9GHz

-1.5GHz.

If my stimulus start and stop crisses over one of these ranges then I see
this happen.

So this may be a feature I never heard of instead of a bug or problem.

Maybe me talking to myself will help some poor bloak searching the threads
someday. lol

Bryan N0LUF

COULD IT BE?

There are three ranges noted on the back label. 50k-300MHz, 300MHz-900MHz, and 0.9GHz-1.5GHz.

If my stimulus start and stop crisses over one of these ranges then I see this happen.

So this may be a feature I never heard of instead of a bug or problem.

Maybe me talking to myself will help some poor bloak searching the threads someday. lol

Bryan N0LUF

UPDATE: It seems this only happens when my stop freq is above 300mhz. Is this normal or is my understanding flawed. I may have never noticed this because I don't recall ever using it that high.

Bryan, n0luf

On 09/02/2025 14:20, CLIFTON HEAD via groups.io wrote:

For a newie using wanting to use NanoVNA which is better the NanoVNA F V2 or the H4

You might like to include the LiteVNA 64 in your list:



Cheers,
David
--
SatSignal Software - Quality software for you
Web:
Email: davidtaylor@...
BlueSky: @gm8arv.bsky.social, Twitter: @gm8arv

On my H4, I recently started having a problem calibrating. During cal the smith chart is sweeping wildly displaying a lot of straight angled lines about the cursor. In the end the cal fails as evidence by measuring the cal standards.

This started after flashing firmware to H4 dislord 1.2.40 though I suppose it could be coincidental.

I opened it and checked for cracked solder joints but didnt see any. Then I flashed it a few more times, testing in between, and finally after 2-3 attempts it started behaving normally again.

Has anyone else seen this before? Maybe I had some setting botched?

Bryan, N0LUF

Depends on what you want. The H4 has less frequency range but I like the
larger screen. I suppose you could get one of each.

Zack W9SZ

On Sun, Feb 9, 2025, 8:20 AM CLIFTON HEAD via groups.io <aecret=
[email protected]> wrote:

For a newie using wanting to use NanoVNA which is better the NanoVNA F V2
or the H4

For a newie using wanting to use NanoVNA which is better the NanoVNA F V2 or the H4

TNX for replies
following the First Interest Groups Law:
"At every question will always follow unwanted suggestions"
73

Il Dom 9 Feb 2025, 11:14 Bruce Akhurst via groups.io <bruce=
[email protected]> ha scritto:

Very hard to see what it would do better than the NanoVNA for filters etc

You don’t need the excess power and the output range is pretty limited for
harmonic filters etc

Very hard to see what it would do better than the NanoVNA for filters etc

You don’t need the excess power and the output range is pretty limited for harmonic filters etc

Here is renormalization in coppermountaintech
Analysis > Fixture Simulator > Port Z Conversion
(z)-c.html

Microwave circuit theories - need for complex impedance, for not complex Z` calculations more simple

Roger,

I believe DiSlord is indeed asking whether the ability to accurately
measure differing DUT input and output ports would be useful. It may not be
used often but there are definitely uses for testing baluns and other
asymmetrical two-port networks. I think “port renormalization” doesn’t
properly describe this type of measurement as opposed to 75/75 ohm
measurements. A different terminology would be better to describe 75/300
ohm measurements but I’m at a loss to come up with a description that makes
sense. Ideas wanted.

Tony AC9QY

On Sat, Feb 8, 2025 at 7:09?PM John Gord via groups.io <johngord=
[email protected]> wrote:

Roger,
I am happy with the in/out impedances being the same. I just didn't want
the renormalization feature the disappear.
--John

On Sat, Feb 8, 2025 at 03:24 PM, Roger Need wrote:

On Sat, Feb 8, 2025 at 12:35 PM, John Gord wrote:

The renormalization is useful for measuring networks (like crystal or

ceramic

filters) which are designed for other impedance levels.

Do you want different impedances on input and output? I believe that

is what

DiSlord is suggesting...

Roger

Roger,
I am happy with the in/out impedances being the same. I just didn't want the renormalization feature the disappear.
--John

N. I. Yannopoulou and P. E. Zimourtopoulos, "Comparing a NanoVNA with a LabVNA Part 2: Three NanoVNAs, Two H4 NanoVNAs, and One HP 8505A VNA", FunkTechnikPlus # Journal, Issue 36, Friday 31 January 2025, Year 12, 36-3, pp 57-77:

On Sat, Feb 8, 2025 at 12:35 PM, John Gord wrote:

The renormalization is useful for measuring networks (like crystal or ceramic
filters) which are designed for other impedance levels.

Do you want different impedances on input and output? I believe that is what DiSlord is suggesting...

Roger

On Sat, Feb 8, 2025 at 09:26 AM, W0LEV wrote:

Why not just use a normalized Smith Chart? Ten the center resistance can
be anything you want.

Smith Chart is only for S11. The Port Z feature also works with S21.

Roger

On Sat, Feb 8, 2025 at 10:55 AM, Team-SIM SIM-Mode wrote:

If the coding does not require a huge complication nor a large resources, it
would be appreciated to have this option of the Z port2, it would also
approach the enhanced response on H4 NanoVNA.

Nizar,

I am not sure what you are saying. The existing Port Z function allows one to calculate the S parameters for another system impedance like 75 ohms. For example if a filter had a designed input impedance of 75 ohms and an output impedance of 75 ohms you could set Port Z to 75 ohms and measure S11 and S21.

I think what DiSlord is proposing is that you could set two different impedances - one for input of the DUT (like 75 ohms) and one for the output (like 300 ohms) and they could be different. DiSlord is that what you are suggesting?

Roger

On Sat, Feb 8, 2025 at 12:51 PM, W0LEV wrote:

But the measurement system - that of the NANOVNA - is always in a 50-ohm
system. To do it correctly, matching networks are required to match
anything other than 50-ohms.

Yes NanoVNA 50Om system, but possible use math to see how this DUT measured in different impedance system
For this S parameters converts to Z (DUT impedance constant and not depend from measured device) and after convert back to virtual Z` measured system impedance. This process named impedance renormalization.

As result measured DUT impedance not change, but S parameters transform

Dave,
The measurement is indeed made in a 50-ohm system, but given a complete (S11, S21, S22, S12) set of S-parameters in a 50 ohm system, it is possible to calculate what the S-parameters would be in a different impedance system. (This works best for passives, less chance of strange non-linearities like oscillations with incorrect terminations.)
Since we only have S11 and S21, we assume that S12 = S21 (almost always true) and S22 = S11 (true enough for symmetrical devices like many filters).
If you have some ceramic filters give it a try. It is interesting to see the bumpy S21 response in the 50 ohm measurement turn into a much smoother S21 in the correct impedance framework.
--John Gord

That isn't the point Dave... When converting back to real values, whether the center 1 represents 50 Ohms or something else makes a difference. Or have I got something wrong here?