Spur at 4.275 GHz on ZS-407
Hello Erik and everyone.
I've recently purchased a TinySA Ultra+ from a local vendor and the unit has an issue.
It is a ZS-407 with HW version V0.5.4 and S/N SU-407-25011571.
It has a spur at ~4.275 GHz that is present regardless of the Spur Removal or Sample Rep settings:?
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 ?  ?
 ? 
When I narrow the frequency bandwidth to 100kHz and turn off Spur Removal, I see that the "spur" is actually five pulses:?
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The instrument passes the self test and calibration successfully.
This issue was present in the factory firmware (I believe it was V1.4-195) and is still present after upgrading to the latest V1.4-197.
The vendor has checked a few other units they have in stock and they show the same spur:
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The vendor assures me that the units are genuine and that they get them directly from ZeenKo.
I also have an older TinySA Ultra (up to 5.3 GHz, ZS-405 maybe, it has no model number on it) and it has no such anomalies.
So my questions are:
- Is this device really genuine?
- Is this a known issue?
- Is it faulty hardware?
- How can this be fixed (if it's possible)?
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Thank you!
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Best wishes,
Andrew
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PS: This is the device in question:
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Re: WinSpectrum III spectrum analyzer question
Thank you for the suggestion to create a dedicated group for WinSpectrum III.
Unfortunately, we don’t have the time required to maintain a separate support group.
However, anyone interested in WinSpectrum III (both 32-bit and 64-bit versions) is welcome to visit:
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There you’ll find the latest versions and updates, as well as a way to contact us if needed.
We greatly appreciate all the feedback and suggestions shared by the members of groups.io/g/tinysa.
Kind Regards
Xavier Junqué
Juan M0WWA
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Re: WinSpectrum III spectrum analyzer question
Would it be possible to create a separate WinSpectrum support group on groups.io?
No problem to point people to that separate group from here.
--
Designer of the tinySA
For more info go to
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WinSpectrum III spectrum analyzer question
Hi,
I'm beginning to use WinSpectrum III and I don't know how to switch
inputs from the application. I works ok if I switch them in the tiny.
Best regards,
Ignacio
--
Este correo electrónico ha sido analizado en busca de virus por el software antivirus de Avast.
www.avast.com
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Re: WinSpectrum III spectrum analyzer application designed for Windows users working with Tiny SA Ultra+
Fair enough, least not vulnerable being kept off the internet. I believe Win10 support finishes up soon. Cheers Dave
On Mon, 24 Mar 2025, 1:45?pm John Cunliffe W7ZQ via , <w7zq= [email protected]> wrote: Dave, some do some don't, unfortunately some of the old R&S and HP do not work. I don't mind using an older OS in the shop,I do not need the newest, after all that computer never goes out to the internet it is on its own network without internet connectivity.
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John
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Re: WinSpectrum III spectrum analyzer application designed for Windows users working with Tiny SA Ultra+
Dave, some do some don't, unfortunately some of the old R&S and HP do not work. I don't mind using an older OS in the shop,I do not need the newest, after all that computer never goes out to the internet it is on its own network without internet connectivity.
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John
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Re: WinSpectrum III spectrum analyzer application designed for Windows users working with Tiny SA Ultra+
Hi John, Have you tried?running?the old apps in Compatibility mode under win10/11,?I had a similar?prob?and?worked?fine in?compatibility mode.
Dave?
Dave, there are two versions, one for WIN 10/11 and one for legacy devices like WIN7 and XP. Since most of my gear in my hobby shop needs WIN7, XP and in a few cases DOS I am maintaining the shop computer at that level. WIN10/11 just throw up trying to run those old programs.
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John
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Re: WinSpectrum III spectrum analyzer application designed for Windows users working with Tiny SA Ultra+
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Re: WinSpectrum III spectrum analyzer application designed for Windows users working with Tiny SA Ultra+
? Tested on Windows XP (Virtual Machine)
Just a quick note to confirm that the current 32-bit version of WinSpectrum III has been successfully tested on a Windows XP virtual machine (VirtualBox).
The application runs smoothly, including full USB communication with the tinySA analyzer, real-time plotting, and logging features.
If you're working in a legacy environment or testing on older systems, this version should work without issues.
? The required STMicroelectronics VCP driver (VID_0483, PID_5740) is already included in the ZIP package.
This is the same driver used for Windows 7 (32-bit), and it installs without problems on XP.
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Re: WinSpectrum III spectrum analyzer application designed for Windows users working with Tiny SA Ultra+
Dave, there are two versions, one for WIN 10/11 and one for legacy devices like WIN7 and XP. Since most of my gear in my hobby shop needs WIN7, XP and in a few cases DOS I am maintaining the shop computer at that level. WIN10/11 just throw up trying to run those old programs.
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John
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Re: WinSpectrum III spectrum analyzer application designed for Windows users working with Tiny SA Ultra+
The developers may have more qf an idea but I wouldn't expect recently developed S/W to reliably function on a OS less than Win10.
Dave
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Re: WinSpectrum III spectrum analyzer application designed for Windows users working with Tiny SA Ultra+
I played around with a win7 computer in XP mode the 32bit version and my original ultra.
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Markers do not work at all, no matter what information entered.
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The curser does not stay hidden and shows up every time there is a change, to fix it one has to uncheck the curser and? then re-check it.
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The points seem to be fixed at 460 or less? no matter if it is single sweep or continues sweep.
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I could not get the waterfall to work, activating the function just freezes everything.
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There have been a few strange disconnects during the testing that I have not yet associated with a special combination of commands.
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That said, I like the large display it is easy on my old eyes given time, this could evolve into something nice and useful.
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John
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Re: WinSpectrum III spectrum analyzer application designed for Windows users working with Tiny SA Ultra+
Well done developing WinSpectrum, easy to use. The only very minor issue I've found is when selecting the Marker tab, the Accept and Cancel options are in Spanish, tested with 64bit Win11,? WinSpectrum version 3.0.1.2??
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Keep up the good work
Cheers Dave VK3DPM
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Re: Output impedance of RF sinewave generator (Tiny Ultra)
Using an external attenuator is the preferred method with any RF generator.
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Some measure the output and use it as feedback to control the RF level, so that it is consistent over a large frequency range.
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This can be messed up when feeding highly reactive loads, so by adding an attenuator into the path, it helps ensure the generator always sees something close to 50 ohms, regardless of the actual load.
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Don't consider modifying the Ultra, you will just add a whole load of additional problems.
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Regards,
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Martin
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On Fri, Mar 21, 2025 at 10:24 AM, R. Maris wrote:
I'll order a 50 ohms BNC attenuator
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Re: Output impedance of RF sinewave generator (Tiny Ultra)
Of course, adding a resistor in an RF-path with impedance target is quite dangerous (only 0402 would constitute a limited risk). Regarding the 'roughly' 50 ohms output impedance: I forgot to mention that an only very minor drop in amplitude below 150 MHz when the load termination is halved (related to the first approach with one termination resistor should be an indication of an output impedance lower than - say - 20 ohms. Before doing final measurements, I have updated the firmware (for the first time) - the firmware could have improved things, you never know.
I'll order a 50 ohms BNC attenuator (yet I see that they are simple series resistors and not a black box with voltage divider - that fits exactly). A good opportunity to also order the defective LNA.
-- An infrequent user of tinySA4 ?
On Fri, 21 Mar 2025 09:59:19 +0100, Erik Kaashoek via groups.io <erik@...> wrote:
Please do not modify the tinySA HW, you will make it worse.
The output impedance is roughly 50 ohm but for best impedance matching you can consider adding a 6 dB external attenuator.
I never do this myself as the output impedance without external attenuator is good enough for me.
Keep in mind the output level is not adjusted when doing calibration, by default is uses the factory settings. There are several settings you can adjust to improve the output level accuracy if needed.
Have a look at the wiki.
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--
Designer of the tinySA
For more info go to
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Re: Output impedance of RF sinewave generator (Tiny Ultra)
Please do not modify the tinySA HW, you will make it worse.
The output impedance is roughly 50 ohm but for best impedance matching you can consider adding a 6 dB external attenuator.
I never do this myself as the output impedance without external attenuator is good enough for me.
Keep in mind the output level is not adjusted when doing calibration, by default is uses the factory settings. There are several settings you can adjust to improve the output level accuracy if needed.
Have a look at the wiki.
?
--
Designer of the tinySA
For more info go to
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Re: WinSpectrum III spectrum analyzer application designed for Windows users working with Tiny SA Ultra+
A 64 bits update is now available. Additionally, following your suggestion Stephen, a 32-bit version targeting .NET Framework 2.0 has been added for better compatibility with older systems. Feel free to download the one that best fits your setup.
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Re: Output impedance of RF sinewave generator (Tiny Ultra)
That means that the output is low impedance, i.e. not 50 ohms? Could I insert a resistor at an appropriate place behind the mux, in the signal path from the generator?
On Thu, 20 Mar 2025 21:43:59 +0100, Erik Kaashoek via groups.io <erik@...> wrote:
For good output impedance you must insert a attenuator of at least 6 dB
--
Designer of the tinySA
For more info go to
-- Erstellt mit Operas E-Mail-Modul:
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Re: Output impedance of RF sinewave generator (Tiny Ultra)
For good output impedance you must insert a attenuator of at least 6 dB
--
Designer of the tinySA
For more info go to
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Output impedance of RF sinewave generator (Tiny Ultra)
Today, as I was going to measure the frequency (sensitivity) plot of a 500 MHz Keysight oscilloscope, I found that the measured amplitude was going to increase by approx. 6 dB from approx. 150 to 300 MHz, and then drops down somewhat. Despite a direct connection using SMA-BNC adapter and direct coupling without coax cable and a 50 ohms scope input. At any case: the behaviour got (expectedly) a bit worse when I selected a high impedance input while using a BNC T-connector for termination with a BNC 50 ohms termination resistor.
After doing some experiments, I discovered this: with the latter configuration I also switched the internal 50 ohms to active state (resulting termination: 25 ohms). It was a nice surprise that the amplitude shown on the screen was really constant over the whole range that was used (up to 500 MHz), while the amplitude under 150 MHz was fairly the same as in the case of a single 50 ohms termination.
The question: what about the output impedance of the generator??
Rob
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Xavier Junqué i de Fortuny
John Cunliffe W7ZQ