Dear David,

How to automatically (bash/wget) fetch file from the server when it's name changes with every release then?

On 22/12/2023 05:10, Zilvinas, LY2SS wrote:

(since topic is about updates)
I would like to ask if it is possible to make an general name f.e. latest.bin
latest.dfu etc in the server.
This would be very easy to get update scripted on client side.

p.s. Thank you for the great tool!

I see no need for that. The TinySA app accepts the full file name as
downloaded. I always use the .bin.

David
--
SatSignal Software - Quality software for you
Web:
Email: davidtaylor@...
Twitter: @gm8arv

On 22/12/2023 02:31, Bob Ecclestone wrote:

I think if Erik just annotates "V" to "Vrms", then there is no confusion as to
which "volt" the instrument is displaying.

Agreed - that's all that's needed.

David
--
SatSignal Software - Quality software for you
Web:
Email: davidtaylor@...
Twitter: @gm8arv

On Thu, Dec 21, 2023 at 11:20 PM, Akai Moto wrote:

Just use dots "v1.4.137", no need to use the dash.

This mixed format comes directly from the git --describe command, which is the most correct versioning b/c it increments the part after the dash with every commit, no need to do it manually (with the danger of forgetting etc.) in an extra edit.

(since topic is about updates)
I would like to ask if it is possible to make an general name f.e. latest.bin latest.dfu etc in the server.
This would be very easy to get update scripted on client side.

p.s. Thank you for the great tool!

开云体育

Hi,
I know you are closing this subject Erik, but I think we need to make a couple of things clear here.

The relationship between Vrms, Vavg, Vpeak, Vp-p is very dependant on waveform.
For a pure sine wave, for Vpeak multiply Vrms by [root 2] and for Vp-p multiply Vrms by [2 x root 2].
For a squarewave, for Vpeak, multiple Vrms by 2.0 and for Vp-p multiply by 4. And Vaverage also equals Vrms.

So trying to correlate a peak-peak voltage reading on a scope compared to a spectrum analyser is very difficult, if not impossible.
In the case of a square wave, we have the classic diminishing odd harmonics.
So which harmonic do you want to correlate exactly with the scope reading? The fundamental you say. So what happens to all the extra "volts" due to the harmonics?
Can you (the operator) determine the harmonic distortion of a waveform on a scope. Unless it is gross, I certainly can't.

I think if Erik just annotates "V" to "Vrms", then there is no confusion as to which "volt" the instrument is displaying.
It is then up to the operator to interpret, and manipulate, that reading as they see fit.

Erik has already included a lot of measurement capability into this instrument that we once had to pay gazzillions of extra dollars for from the Big Guys.
Channel Power is just one that comes to mind.

So lets not get too carried away requesting semantic features and use these instruments as their design dictates.
A scope measures voltage relative to time, a spectrum analyser measures power relative to frequency.

Whether we are hobbyists or professional engineers, it is up to us to interpret the measurements we make.
Occasionally, both groups will misinterpret the results. That is our fault, not the instruments fault.

Just my 2 cents(rms) worth:-)

Cheers...Bob VK2ZRE

That's interesting. From my personal perspective, not saying you are right or wrong, in 40+ years of working with RF I have never measured any kind of volts with a SA. Even probing circuits with a HP high impedance active probe it was still dB. All of my RF generators are calibrated in dB and RMS volts. The only place I use P-P is when it is called out in circuit diagrams or voltage charts, and then the tools of choice are a scope or a milliVolt meter. Which are typically the instruments specified for the reference reading if they are specified at all. It is worthy of note that a 50 Ohm input impedance SA will likely read differently than a high impedance scope.

I see that Erik is going to accommodate your request. Happy measuring! :)

73

-Jim
NU0C

On Thu, 21 Dec 2023 22:04:08 +0100
Ma?l H?rz via groups.io <mh-nexus@...> wrote:

I am curious, what is your use case for measuring P-P with a spectrum
analyzer?

Just like you mentioned yourself:

P-P is easy to measure and not dependent on waveform purity but does
not translate easily to power in a scope if not a pure sine wave.
With a spectrum analyzer you always have a sine wave at the
fundamental frequency of a complex wave.

Main reason: Vpp is easy to measure (and see) on scopes.

A simple use case is looking at the output of a generated signal at a
desired frequency and seeing if the different instruments agree and get
a feeling how they correlate, visually. Some simple signal generator
chips specify their output in terms of Vpeak/Vpp. Yes, you could convert
it to dBm, but sometimes Vpp is just more "direct".

Similarly, you might want to look at an oscillator and see quickly how
close its Vpp is compared to the fundamental frequency shown on the
spectrum analyzer. You can then dig deeper to find out the causes, such
as overlayed noise/distortions etc, and see what other frequency
components exist. But first you can have a first high level impression
how much your signal reaches its expected output level.

Or you might have a sine wave that is split up with a directional
coupler, and compare outputs easily on the scope and on the spectrum
analyzer (and their respective power levels). I don't need to
characterize the full frequency spectrum/harmonics/other frequency
components always. Often simple sine waves are enough for many experiments.

--

73

-Jim
NU0C

Erik,

While you’re in such an accommodating mood (!), I wonder if you’d consider adding the Ham Band shading feature to the Ultra, preferably with a CONFIG choice of band plan to match all the countries where the device is sold. (I think it would only take three.) I’m sure many users are hams, and would find this feature very handy.

We assume the SA4 is running the latest fimware v1.4-137 , and re-calibrated ?

Thanks Istvan for the SA4 changelog file.

Attached here is the modified file (my edits for just version syntax). They now match the filenames.

It's just me from being in world of code versions, I don't like use of mixed chars, like the dot and the dash "v1.4-137", etc. Just use dots "v1.4.137", no need to use the dash.

[MAJOR] dot [minor] dot [updates/fixes]

Cheers.

Let's close this subject.
I will consider adding Vpp as one of the units if it fits in the various output fields
--

A given voltage (or current) that doesn’t specify peak, peak-to-peak, RMS or average is, by default, assumed to be RMS. Knowing people have different needs doesn’t change that. If you need P-P, simply multiply the RMS value by 2.828. Everyone has a cell phone with a calculator, so adding P-P (or avg) to the tinySA would just make the already complex menu tree needlessly more complex. Just so you can compare it with your scope? Really?

I am curious, what is your use case for measuring P-P with a spectrum
analyzer?

Just like you mentioned yourself:

P-P is easy to measure and not dependent on waveform purity but does
not translate easily to power in a scope if not a pure sine wave.
With a spectrum analyzer you always have a sine wave at the
fundamental frequency of a complex wave.

Main reason: Vpp is easy to measure (and see) on scopes.

A simple use case is looking at the output of a generated signal at a
desired frequency and seeing if the different instruments agree and get
a feeling how they correlate, visually. Some simple signal generator
chips specify their output in terms of Vpeak/Vpp. Yes, you could convert
it to dBm, but sometimes Vpp is just more "direct".

Similarly, you might want to look at an oscillator and see quickly how
close its Vpp is compared to the fundamental frequency shown on the
spectrum analyzer. You can then dig deeper to find out the causes, such
as overlayed noise/distortions etc, and see what other frequency
components exist. But first you can have a first high level impression
how much your signal reaches its expected output level.

Or you might have a sine wave that is split up with a directional
coupler, and compare outputs easily on the scope and on the spectrum
analyzer (and their respective power levels). I don't need to
characterize the full frequency spectrum/harmonics/other frequency
components always. Often simple sine waves are enough for many experiments.

You can’t be an EE then. Am I right?

So because I want to compare what I read visually on a scope's screen
and don't follow what you are used to, I am not a professional....

Just respect that people have different needs. Thanks

I am curious, what is your use case for measuring P-P with a spectrum analyzer?

73

-Jim
NU0C

On Thu, 21 Dec 2023 18:11:20 +0100
Ma?l H?rz via groups.io <mh-nexus@...> wrote:

Given the non-perfect mapping of a scope to a spectrum analyzer, I think
it makes sense to assume you only compare pure sine waves, and as such
Vpp would be helpful.

You can’t be an EE then. Am I right?

Depends on the waveform.

Would that conversion factor be correct for any wave form? E.g. is the
power of the fundamental of any wave form always only related to the Vpp
as observed on a scope, or does it also depends on the shape of the wave
form?

I have no definite answer to the question regarding the fundamental, but
at least for the non-decomposed signal, it depends on the waveform.
For example, for triangular waves, the conversion formula would be
different from sine waves:
Vpp = 2*sqrt(3)*Vrms
vs
Vpp = 2*sqrt(2)*Vrms

However many scopes measure Vrms simply by probing at 0.707 of the peak
voltage at some horizontal point/trigger point. So that would not be the
correct value for signals that aren't completely periodic, either.

Aside from scopes in FFT mode, I haven't seen them offering measurements
in dBm.

Given the non-perfect mapping of a scope to a spectrum analyzer, I think
it makes sense to assume you only compare pure sine waves, and as such
Vpp would be helpful.

Would that conversion factor be correct for any wave form? E.g. is the power of the fundamental of any wave form always only related to the Vpp as observed on a scope, or does it also depends on the shape of the wave form?
--

Vpeak = Vrms * 1.414
Vpp = 2*Vpeak

Or more precisely Vpp = Vrms * 2 * sqrt(2) for a pure sine wave, as
mentioned in