No mention has been made on a lot of the installs as to if they installed via the store, or an apk.

The store looks at device type (tablet, phone, etc.), Android version, and perhaps other things to determine if it should allow a download, and I beliece that stuff is set by the software owner/publisher, not determined by the app directly.

As a counter argument, if the kernel were the factor, kernel upgrades as part of Android patching would cause already loaded apps to no longer work, and I have never see that happen (or a bunch of patches immediately after an Android patch).

And I speak to Linux (or *nix in gereral) since it's what Android is rooted, and it's because it's where my professional experience lies (Ultrix, AIX, SunOS, Solaris, Ultrix, Irix, whatever Convergent called thiers, SysV68K SysV88K (Motorola) and a few others . . .

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

Jerry,
You're stuck on this point but it's simply not true. It's not the kernel.

The issue here is the API level used to build the app. That's it. It's the
API level. When the Play Store says that an app is not compatible with the
version of Android on your phone, it's the API version shipped with that
version of Android and how far back it supports, as well as the minimum API
version the application was built to require Nothing more, nothing less.
Has zero to do with the kernel. The play store has no idea what kernel your
phone is running.

I posted the page with the proof (compatibility levels for each Android
release). For the record, I've been an android developer, kernel hacker,
and reverse engineer for over ten years. XKCD "Recognized Developer" for my
contributions to the rooting community.

The same thing is true for Apple applications. I build TQSL software for
MacOS, with OSX 10.10 as the minimum allowed API version. If you're running
anything 10.10 or later, it'll work fine - which means several different
kernel versions from 10.10 to 15.2 - but if you try to use 10.9 it'll fail
as the userland libraries don't have the API interfaces that the
application needs. 10.10 came out in 2014, so Apple has maintained
kernel compatibility for 10 years.)
As Tim said, the kernel changes but remains largely backward compatible.
The userland libraries do not.

And finally, Windows - same issue, but much more tedious due to DLL Hell.
The same application works from Windows XP to Windows 11 without changes
(That's what, 23 years of kernel updates and no compatibility issues.) .The
kernel doesn't matter.

-Rick

On Mon, Dec 30, 2024 at 7:21 PM Jerry Stuckle via groups.io <ai0k=
ai0k.net@groups.io> wrote:

Well, first of all, Linux is only one OS out there, so it is not really
a great reference. There are many other OS's out there, several of
which I've worked on, from embedded systems to mainframes.

But I never said an update to libc forced a kernel update. In fact,
just the opposite. The kernel is the lowest level and everything must
interface to it. And while developers do their best to maintain
compatibility, it's not always possible. This is why sometimes an
application requires a certain library version.

If what you are saying is true, why is it I (at the latest kernel level)
can't install it but other can?

73,
Jerry, AI0K

--
Rick Murphy, D. Sc., CISSP-ISSAP, K1MU/4, Annandale VA USA

Sure, I'm an engineer. I've been using professional VNAs for some
40-years. I salute the creators of the NANOVNAs! It works just like the
professional units and quite intuitive to me. Keep it up. I have no
problem with the "complexity" of the NANOVNAs.

You would be much happier with the Rig Expert offerings as they are
designed as a technician tool at the top of the tower.

Leave the NANOVNAs alone.

Dave - WØLEV

On Mon, Dec 30, 2024 at 7:29 PM Kirk Kleinschmidt, NT0Z via groups.io
<sohosources@...> wrote:

OP: Your thoughts are legit, but you will face lots of opposition from
existing users and from the developers, as these VNAs are designed to have
every possible feature and are built to perform just enough above the
lowest possible performance standards to keep costs to a minimum and folks
buying.

THEY ARE NOT BUILT AT ALL FOR EASE OF USE.

As a comparison, compare and contrast a ham radio built by hams, but
incorporating DSP/SDR elements...to an SDR built by non-ham programmers. :)
One is easy to use while the other is like using C++ as a radio
interface...in a translated language...with inverted colors...
My phone has a dual interface, which would be welcome on hobbyist VNAs. In
full-feature mode it's the latest and greatest version of Android. In
"easy" mode it lacks many features but is super easy to use for common
tasks.
Hint, hint, developers?
Regards,
Kirk, NT0ZRochester, MN

My book, "Stealth Amateur Radio," is now available from
www.stealthamateur.com and on the Amazon Kindle (soon)

On Sunday, December 29, 2024 at 09:40:37 AM CST, aeternus.arcis via
groups.io <aeternus.arcis@...> wrote:

Hello.
I just wanted to ask if there is any interest from the community or the
developers to make the menu easy for radio amateurs, for people that are
not engineers? Currently the menu is a big mess with a lot of options and
sub-options and so on. So if you want to make a simple measure, you have to
go in many menus to change many settings. I know this gives a lot of
control, but I will be very nice to have a few buttons on the main screen,
like a main menu, that take you to the most used measurements, with all of
the settings already set, with bigger font and a few buttons to change some
settings only to that current measurement. I also do not know if this is
something that the hardware supports.

--

*Dave - WØLEV*


--
Dave - WØLEV

Well, first of all, Linux is only one OS out there, so it is not really a great reference. There are many other OS's out there, several of which I've worked on, from embedded systems to mainframes.

But I never said an update to libc forced a kernel update. In fact, just the opposite. The kernel is the lowest level and everything must interface to it. And while developers do their best to maintain compatibility, it's not always possible. This is why sometimes an application requires a certain library version.

If what you are saying is true, why is it I (at the latest kernel level) can't install it but other can?

73,
Jerry, AI0K

Great references, thanks!

About differences TDR and VNA TDR
https://incompliancemag.com/time-domain-measurement-tdr-or-vna/
https://coppermountaintech.com/what-is-the-difference-between-tdr-and-vna-time-domain-measurement/

Also about VNA TDR options
https://helpfiles.keysight.com/csg/m9485a/applications/timedomain.htm

On Dec 30, 2024, at 10:33, Roger Need via groups.io <sailtamarack@...> wrote:

On Mon, Dec 30, 2024 at 01:58 AM, G8HUL wrote:

The Tx does not see an SWR it sees an impedance, it is the transmission line
that has the standing waves and that must be based on the impedance of the
line NOT the load that the Tx 'likes to see'.

Yes it is the transmission line that has the standing waves on it. However as I stated in my previous post the transmitter power amplifier is designed for a specific load which is 50 ohms for ham transmitters. Modern solid state transmitters contain a circuit that calculates SWR based on the load impedance at the output connector on the Tx. The Tx circuitry cuts back on the output power as the SWR rises.

Maybe. It kind of depends on the amplifier - some just fold back when the voltage at the output terminals gets too high (to protect the transistors). That is, the protection circuit on most amps doesn’t actually calculate the SWR - it protects the devices against whatever the limiting parameter is (voltage is the quick death, current or heat is the slow death).

Imagine an amplifier with zero output impedance.

OP: Your thoughts are legit, but you will face lots of opposition from existing users and from the developers, as these VNAs are designed to have every possible feature and are built to perform just enough above the lowest possible performance standards to keep costs to a minimum and folks buying.

THEY ARE NOT BUILT AT ALL FOR EASE OF USE.

As a comparison, compare and contrast a ham radio built by hams, but incorporating DSP/SDR elements...to an SDR built by non-ham programmers. :)
One is easy to use while the other is like using C++ as a radio interface...in a translated language...with inverted colors...
My phone has a dual interface, which would be welcome on hobbyist VNAs. In full-feature mode it's the latest and greatest version of Android. In "easy" mode it lacks many features but is super easy to use for common tasks.
Hint, hint, developers?
Regards,
Kirk, NT0ZRochester, MN

My book, "Stealth Amateur Radio," is now available from www.stealthamateur.com and on the Amazon Kindle (soon)

You'll probably get along much better with a RigExpert analyzer.
I use this one:
https://rigexpert.com/products/antenna-analyzers/aa-230-zoom-option-ble/
and I think it's what you're looking for.
However, NanoVNA offers much more possibilities of use, it just needs to be
learned.

73!
Costin, YO8RCD <https://yo8rcd.blogspot.com/>


În lun., 30 dec. 2024 la 20:43, Roger Need via groups.io <sailtamarack=
yahoo.ca@groups.io> a scris:

On Mon, Dec 30, 2024 at 12:45 AM, <aeternus.arcis@...> wrote:

All I asked was a possibility of simplified menu without removing the advanced
options. For everyone that thinks it is more complicated than it needs to be,
which I know is not just me.

A developer named Reald did make a big font version with SWR display about 4 or 5 years ago and you could try that out and see if it works for you. The links are in archive posts. A simplified menu been discussed several times in this group over the years and no one stepped up to do it. Not enough interest I guess as most of us like all the VNA features. The code is open source so feel free to modify it to do what you want.

Roger

On Mon, Dec 30, 2024 at 01:58 AM, G8HUL wrote:

The Tx does not see an SWR it sees an impedance, it is the transmission line
that has the standing waves and that must be based on the impedance of the
line NOT the load that the Tx 'likes to see'.

Yes it is the transmission line that has the standing waves on it. However as I stated in my previous post the transmitter power amplifier is designed for a specific load which is 50 ohms for ham transmitters. Modern solid state transmitters contain a circuit that calculates SWR based on the load impedance at the output connector on the Tx. The Tx circuitry cuts back on the output power as the SWR rises.

The amount of reflected power will depend on the mismatch between the line impedance (75 ohms) and the
impedance of the load. The design impedance of the Tx is irrelevant.

Yes the mismatch between the line impedance and the load is what determines the VSWR at the load and the reflected power. However the design impedance of the transmitter is relevant. This TX source impedance will determine how much of the reflected power will be reflected back to the load. If it is 50 ohms none will be reflected back but transmitters are not designed with a 50 ohm source impedance.

Leaving the settings at 50ohms may well give you an equivalent SWR of the
impedance that the Tx sees, but tells you nothing about they standing waves on
the 75ohm line. For Example, if a 1:1 SWR was indicated with a 50 ohm setting
you might believe that there were no standing waves on the 75 ohm line, which
would not be correct.

Yes that is true but the transmitter will be able to output its full rated power with the SWR = 1. And if the transmission line used has low loss there will be little power lost in the transmission line.

Roger

Yes, it is not labeled 'TDR' in the menus. Instead it is appropriately labeled 'Transform', since it is not a true TDR, but simulation of a TDR via Fourier Transform. On the menus: Display -> Transform. Usually the "Low Pass Impulse" is an appropriate selection. There are some videos you can find online that describe its use. Also messages in this group from a long time ago. It requires setting up the frequency scan range appropriately for the corresponding time-length you require, which can be a bit counter-intuitive, and you need to take care to set it appropriately to avoid aliasing, which would give a false answer. But it works very well once you know how to set it up.
Stan KC7XE

Does the nanoVNA have a TDR function? For some reason I thought it did, but
I can't find it in the menu.

Zack W9SZ

<https://www.avast.com/sig-email?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=webmail>
Virus-free.www.avast.com
<https://www.avast.com/sig-email?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=webmail>
<#DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2>

It has long been established that R&L electronics is one of the most
reputable sources of the NanoVNA, if not THE most reputable source. This
link brings up a search on all the variants of the NanoVNA that they have
available -- and at the lowest prices I have seen, IMHO:

https://www2.randl.com/index.php?main_page=advanced_search_result&search_in_description=1&keyword=NanoVNA

-- Rich WB2GXM

On Sun, Dec 29, 2024 at 11:56 AM VE6LX via groups.io <dclarke2=
telus.net@groups.io> wrote:

there seems to be a debate as to where or how to purchase a nanoVNA. They
are all made in various factories in Mainland China. the issue is not so
much (in my mind) if it is a clone as in reality they are al a clone of the
original open source work. It is more of finding and dealing with a
reputable source. or use another intermediary such as Amazon where if there
is a problem you can return the item to Amazon. this a all beside
attempting as a new comer to the technology choosing which of the multiple
firmware versions supported or not supported software versions. This is on
the nanoVNA.com site they list the vendors they deal with the supply a
known product,
Those of us who have worked with the Lab Grade Network Analyzers will be
amazed with the actual performance of a similar device we can now hold in
our hands that for instance we can use to test our antennas. The lab grade
device does not lend itself to working in the field (I actually had one
equipped in a purpose built field work case) While the Lab Grade is a
wonderful piece of kit you cannot beat the fact you can now hold in you
hand a device you can use while at the top of a tower attached directly to
the antenna in question.
As long as you obtain one that works and you become accustomed to the
controls and learn the techniques of using the device you will be very
pleased with have the convenience of delving into the mystery of wonderful
world of antennas and how to improve them beyond the simple SWR at the
desired operating frequency. I hope that helps. Dave VE6LX

Are you trying to use 75 ohm coax with a transmitter designed for 50 ohm?
If so you should be not be using the DiSlord impedance setting which changes the system impedance to 75 (or 77) ohms.
You want the SWR measurement to be based on what the transmitter will see.

The Tx does not see an SWR it sees an impedance, it is the transmission line that has the standing waves and that must be based on the impedance of the line NOT the load that the Tx 'likes to see'. The amount of reflected power will depend on the mismatch between the line impedance (75 ohms) and the impedance of the load. The design impedance of the Tx is irrelevant.

Leaving the settings at 50ohms may well give you an equivalent SWR of the impedance that the Tx sees, but tells you nothing about they standing waves on the 75ohm line. For Example, if a 1:1 SWR was indicated with a 50 ohm setting you might believe that there were no standing waves on the 75 ohm line, which would not be correct.

73
Jeff G8HUL

I think some people are missing the point, or just do not want any changes to the way they are doing things. Which I said is not what I want to do. When I buy something, I learn everything about it. That does not mean that it is doing the things in the best way. I know how it works. I watched the videos. I am really grateful for that, to those people, because without them it would be even worse to learn this. All I asked was a possibility of simplified menu without removing the advanced options. For everyone that thinks it is more complicated than it needs to be, which I know is not just me. But this is a lot like in Linux - when someone suggests GUI for a terminal program, all of the people that use only terminal jump that he should learn the terminal or just use Windows.

SWR was just an example. It is not the only thing I need and after all, this is not only about me.

I understand about support being more difficult. I think something can be done about that, but it needs time. It is not easy for sure.

So, thanks for the suggestions. Like I said, I watched videos and read guides. I learned and I am still learning. But that does not make it simpler. So if someone is ever interested in simplifying this menu, contact me. I do not want to be a programmer, but can help with the design.

Bottom right hand corner of menu indicates it is for Hugen’s (Zeenko) -H and -H4 with older version 1.1 firmware by DiSlord

I said that they are a layer away - apps go through the system shared libraries to access kernel functions in most cases, so reallynare well isolated. 36 years in *nix as a professional, including System-V at the source level, taught by AT&T, (If Win*/MS does something tupid, I'm not at all surpised . . . ). Essentiallynhave my own Linux distro, and can't recall a libc update forcing a kernel update (or the opposite) other than the change away from a.out binary format. I do load software from my own source builds wherever possible though, due to app symbol/lib version issues . . .).

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

Tim,

I've worked on multiple APIs in the 50+ years I've been programming (including as an IBM employee) on everything from MS-DOS 1.0 to mainframe operating systems like MVS.

Yes, few applications interface directly with the kernel. But the API consists of two parts - the interface and the implementation.

The interface is what the applications see. The implementation is how it interacts with the kernel and other resources. A change in the kernel can definitely change the implementation (which is why you have version-specific libraries).

But sometimes the changes in the kernel can't be covered by the implementation without changes to the interface. And yes, it does happen which is why application sometimes have version specific libraries.

So you can't say that changes in the kernel do not affect applications. They definitely can. That may or may not be the problem here but not knowing the reason for the rejection the biggest thing I see between being able to download or not is the kernel version.

Jerry, AI0K

Of course, given that they’re not resistive 50 ohms on both sides, the fact that there’s a “mismatch” might not be a big deal - For instance, a DC power supply has a 0 ohm output impedance, and transfers as much power to the load as it will take (given the voltage).

The whole emphasis on matching is sort of a “design help” back in the day before good modeling tools existed, and when getting gain was difficult.