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This shows what I'm considering for my default Smith grid colors. The user can override the defaults for any color (except text), as shown in the second image.

I may do some grid tuning before I release this.

Brian

At when selected Zeenko then one may order a NanoVNA H4 HW version 4.3
Enlarging the photo of the backside of the housing,? it shows HW version 4.4_ZK

I found at the page descrition why HW version 4.4_ZK is released:

"The latest version is NanoVNA-H rev3.6 and NanoVNA-H4 rev4.3. NXP has discontinued the dual balanced mixers SA602A/SA612A/NE602A/NE612A in November 2022,
Hugen is using ZeenKo NE602A to replace the SA602A/SA612A starting with the NanoVNA-H v3.7 and NanoVNA-H4 v4.4 versions,
and that the version also improves the dynamics when using the base wave.

I am curious what the improvement of the dynamics entails.Doesanyonehaveexperiencewiththis?

I've posted a new version of the plotter with admittance here:



Brian

I think that having two grid colors is pretty important to help visually distinguish between the impedance and admittance grids. Traditionally impedance has been plotted in red and admittance in green or blue.
Thanks for your work.
73, Don N2VGU

On Tue, Apr 29, 2025 at 08:21 AM, Donald S Brant Jr wrote:

I suspect that the expanded-center function would be most useful for the
majority of the users

That's what I was hoping, Don. It was so easy to implement!

I think I'm going to leave two grid colors for another time. I could do two gray intensities without much trouble, but I don't think that would help much.

Incidentally, I have no plans to label the grids. To do that properly requires a smaller font, which I don't have. I assume people mainly use the grids for basic orientation and then use a marker to extract values.

Brian

There is a hook/mouse click "box" in nanosaver to reset any previous cal.
Look for it and click it.

Dave - W?LEV

On Tue, Apr 29, 2025 at 5:02?AM Fran?ois via groups.io <18471=
[email protected]> wrote:

Using nanaovna-saver, on a -f, I noticed that sometimes the circle on the
Smith machine (on a simple capacitor, for example) could be larger than the
grid circle.

Now, systematically, even before calibrating with nanaovna-saver, I
perform a RESET on the case, which nanovna-saver doesn't seem to do (0.3.8
because W7). This RESET solves the problem.
--
F1AMM
Fran?ois

--

*Dave - W?LEV*


--
Dave - W?LEV

On Tue, Apr 29, 2025 at 09:28 AM, Brian Beezley wrote:

Would a magnification function be helpful?

Analog Instruments (Phillip Smith's firm) sold expanded Smith charts of 3 kinds: expanded about the center with two magnification factors IIRC, and expanded about the high- and low-impedance areas, the latter two for working with open- and short-circuited stubs respectively. They also made admittance charts and charts with negative real part, for parametric amplifiers, oscillators, and the like. I have samples of most of them in a tote somewhere......

I suspect that the expanded-center function would be most useful for the majority of the users; I doubt that anyone is doing graphical solutions of stubs any more..
73, Don N2VGU

Here's what I have at the moment. I can see that two grid colors are important so let me see how much trouble that is.

Brian

Try again...

Here is an example with the display and the captured movement to implement a matching system.

I see. Displaying both grids simultaneously is easy. Do you also need impedance and admittance values
displayed at the same time?

Yes, that is helpful

73
Jeff G8HUL

On Tue, Apr 29, 2025 at 07:05 AM, G8HUL wrote:

The whole point of displaying both impedance and admittance charts
simultaneously is that it make visualizing matching much easier.

I see. Displaying both grids simultaneously is easy. Do you also need impedance and admittance values displayed at the same time?

The images show what now happens when you click the mouse wheel.

Brian

On Tue, Apr 29, 2025 at 06:28 AM, Brian Beezley wrote:

Something else I've wondered about. This is an 820 pF capacitor from 50 MHz to
4 GHz. There's not much to see. Would a magnification function be helpful? Or
do people just not worry about detail in this kind of plot?

Yes, magnification in particular around the Zo of the chart is quite useful and that is a feature available
on several simulators. Conversion from S to mS or even uS is also an automatic process to improve readability.

On the Z and Y chart. To clarify, Brian, they are OVERLAID. Both appear as a single chart. A toggle permits Z to be on/off and then
further toggle permits Y to be on/off while an additional toggle permits both ON.

Fundamental to LC matching is the arithmetic to convert from series Z to equivalent parallel Y. This can be accomplished
on a single Z chart. However, it is facilitated by displaying both charts Z and Y at the same time so that the SHUNT (Y) movement
is obtained from the admittance chart and SERIES (Z) movement is obtained from the impedance chart. By movement, I mean along
reactance or susceptance contours.

The whole point of displaying both impedance and admittance charts simultaneously is that it make visualizing matching much easier.

Adding series C moves CCW on the impedance chart, shunt C CW on the admittance chart
Adding series L moves CW on the impedance chart, shunt L CCW on the admittance chart

Other transforms are also visible.

73
Jeff G8HUL

________________________________________
From: [email protected] on behalf of Brian Beezley
Sent: Tuesday, April 29, 2025 13:56
To: [email protected]
Subject: Re: [nanovna-users] Smith Charts


Here's how it looks at the moment. I'm thinking of providing a different background color for admittance, but the grid is so different that I'm not sure that's necessary.

Brian

Something else I've wondered about. This is an 820 pF capacitor from 50 MHz to 4 GHz. There's not much to see. Would a magnification function be helpful? Or do people just not worry about detail in this kind of plot?

Brian

Here's how it looks at the moment. I'm thinking of providing a different background color for admittance, but the grid is so different that I'm not sure that's necessary.

Brian

On Tue, Apr 29, 2025 at 05:05 AM, alan victor wrote:

To facilitate matching the 2 charts are overlaid in 2 colors. The immitance
chart used red and green and the one I used had less density on contours.
Consider the possibility of a toggle between them.

I don't quite follow this. You click on Admittance to plot admittance. Otherwise it plots impedance. The grid and marker annotation change. The curves remain the same.

In looking at admittance for some filters renormalized to 1000 ohms, even mS was too small. Currently the marker annotation switches to microsiemens when the admittance magnitude is less than 10 mS. That threshold seems about right, but I may adjust it.

Brian

Here is a portion of the immittance chart. Less contour density is still workable.
A toggle feature is available on the program I use to assist in clarification.

Yes on mS.

To facilitate matching the 2 charts are overlaid in 2 colors. The immitance
chart used red and green and the one I used had less density on contours.
Consider the possibility of a toggle between them.