Frequency Response Analyzer with Bode Plots

[hexamer]

Thank you for reporting your experience. Can you tell me what error code you're getting during initialization?

Sure, this is the error message I see with 5444D scope (serial number obscured **** by me)

Code: Select all

ps5000aSetChannel( 16384, 2, 0, 0, 0, 0 );Fatal error: Failed to disable channel: 290
Status: 5444DMSO S/N: IO716/**** successfully initialized.

Looking a little closer at this now. I think the issue reported by both whichislovely and lazy_electron may be a real issue (not just under-powered USB ports).

In the error reported: ps5000aSetChannel( 16384, 2, 0, 0, 0, 0 );Fatal error: Failed to disable channel: 290

The code is trying to disable channel C (2), which should be valid since power is not applied. Since I don’t see this happening on my PS5444A, it makes me wonder if something is different on a PS5000D scope (both reporters).

Can anyone confirm whether they see this issue on a PS5000D scope? Simply try to connect to your PS5000D series scope with no auxilliary power applied.

[mnni]

Hi Aaron

I got both an 5000D and 5000A version

And yes there is a issue with the detection of auxiliary Power for the 5000D but i am not sure if it also goes for the A/B versions as i just updated to newest SDK before i stepped on this issue at home, the A version is at work where i used it in a fuel cell stack impedance measurement application where i measure the impedance on multiple cell groups in the stack at the same time with very good results.

anyway i had a brief look in the code when i stepped on to the issue and i think maybe Picoscope have added new functions to detect power status of the scope, but i didn't go more into it than this as i have been busy with other stuff.

[bengarbuttchiaro]

Hi,
can you confirm whether this issue makes the FRA unusable with the 5000D series? or that it just requires the external power connected or otherwise.

If there's a workaround I may be looking to buy one of these ASAP, otherwise I'll have to look elsewhere..
Thanks

[Martyn]

The Set Channel command will return the following error code if the channel is either Chan C or Chan D if the power supply is not connected, even if you are just disabling it

Code: Select all

#define PICO_CHANNEL_DISABLED_DUE_TO_USB_POWERED    0x00000122UL

[vichiker]

Does this program support the 6403D? I downloaded the FRA4PicoScope_0.7.3b.msi file but I see nothing happens. I do not see where can execute the downloaded file or see any icon where to open the FRA4 window. Thank you so much for your kind help. I am not a software geek. It is very difficult to me to go through this process.

[hexamer]

Does this program support the 6403D? I downloaded the FRA4PicoScope_0.7.3b.msi file but I see nothing happens. I do not see where can execute the downloaded file or see any icon where to open the FRA4 window. Thank you so much for your kind help. I am not a software geek. It is very difficult to me to go through this process.

Hello and sorry for the delayed response. Seems I'm not getting notifications on this thread.

The code has been setup to handle a PS6403D ever since I first made a release in 2014, but I don't see anyone reporting success with that scope, and I don't have anything in that family to test with. So, it's entirely possible there's a bug preventing its use. Here are a few questions to help diagnose:

1. Does the PicoScope application successfully open the scope?
2. Did you install the latest 32 bit SDK?
3. There are a couple bugs I've fixed since 0.7.3b which haven't made it into a released version yet:
   - If you have neither the SDK or PicoScope application installed Fra4PicoScope will silently crash on open
   - If the app does not find a scope, it will ask you if you want to use a demo scope. The dialog box for that question sometimes goes to the background and it makes it look like the app crashed. Try a alt-tab or minimize all windows to see if you can find it.
4. Can you post the Fra4PicoScope log text for me to see what you mean by "nothing happens"?

Thank you,

Aaron.

[hexamer]

Hi,
can you confirm whether this issue makes the FRA unusable with the 5000D series? or that it just requires the external power connected or otherwise.

If there's a workaround I may be looking to buy one of these ASAP, otherwise I'll have to look elsewhere..
Thanks

It should only require that DC power is applied. I am investigating a fix for this issue, so the next release should remove such restriction.

[Donny001]

Hi Mr. hexamer,
I met a problem when using Picoscope 5444D-034 with FRA version 0.7.3b.
The program can detect the scope but can not initiate the scope and it gives an error message as below picture . Could you please help to check what the issue maybe?
I need to use this scope to test my DC-DC converter loop gain.
Thank you and hope to get your response soon.

[hexamer]

Hi Mr. hexamer,
I met a problem when using Picoscope 5444D-034 with FRA version 0.7.3b.
The program can detect the scope but can not initiate the scope and it gives an error message as below picture . Could you please help to check what the issue maybe?
I need to use this scope to test my DC-DC converter loop gain.
Thank you and hope to get your response soon.

Hi Donny,

I hope I can help you, but I can't predict how far we'll get with this. From what I can tell, the PS5444D-034 model is the PicoScope hardware sold by Vector for their "Option .Scope" product. I can't tell for sure, but I would guess that it does not identify the same as a PS5444D, which is why it can't be opened.

I don't know what other differences there may be in its firmware / operation vs a standard PS5444D, so I could not guarantee that it would even work for FRA. If you want to try at your own risk I could make a special version of the FRA application to try for yourself. However, if we run into issues, I can't promise I have the time to investigate.

Thank you,

Aaron.

[Nicosten]

Hello,

I have a customer from a large aero company who tested the FRA in comparison with desktop instruments.
The advantage of the Pico based FRA is the portable solution vs desktop.
Now he sees two improvements to bring its performance at the same level:
1- we would like to see the signal in real time during the plot construction - running PicoScope concurrently or having a signal display window helps the operator to rapidly 'see' a device saturation in real-time.
2- it would help to have graphical tools to inspect the curves , like zooming or point by point scrolling.

[hexamer]

Nicosten,

Those are both excellent suggestions. The second one is already implemented, but I haven't made a release yet. I'll post some screenshots so you can see what is available. On the first one, I've previously envisioned having a separate window to display the (already existing) diagnostic time domain plots as the FRA is progressing. Because the data capture needs to be in block mode it would only update the plots once the whole waveform for a frequency point is captured. However it seems that would solve the problem posed.

Thank you,

Aaron.

[stereovintage]

Hi Aaron,

After a few weeks of testing some 2406B, i encountered a problem with the FRA4PicoScope application.
Although we have installed the SDK32 bit, the application keeps giving the same error "Signal generator plugin not configured".

We tested it on different PCs with Win 7, Win 10 and Win 11 and encountered the same problem.
I attach files with screenshots: https://1drv.ms/b/s!AjcChqVMGWQ6iqok-RQ ... g?e=C6yKJl

Thank you,
Fabio

[hexamer]

Hi Aaron,

After a few weeks of testing some 2406B, i encountered a problem with the FRA4PicoScope application.
Although we have installed the SDK32 bit, the application keeps giving the same error "Signal generator plugin not configured".

We tested it on different PCs with Win 7, Win 10 and Win 11 and encountered the same problem.
I attach files with screenshots: https://1drv.ms/b/s!AjcChqVMGWQ6iqok-RQ ... g?e=C6yKJl

Thank you,
Fabio

Hi Fabio,

I think I know what's going on and can help.

1) Firstly, the external signal generator option (File->Connect Signal Generator) is probably not relevant for you since you have a PS2406B which has a signal generator. That feature is for scopes without a signal generator or where you need to use an external signal generator with greater capability than the one built into the scope. And to use it you need to have developed or acquired a plugin. To date, I know of no one besides myself that's done that

2) I think the problem your experiencing is that with the default settings (start frequency = 1 Hz, low noise mode with 16 cycles), the initial step of the FRA can take at least 16 seconds. And it can take even longer depending on the circuit and auto-ranging. Maybe it looks to you like the application is doing nothing and so you cancel? If you want to get more frequently updated info on what's going on, go into the verbosity settings (Tools -> Settings -> Log Verbosity) and turn on things like Step Trial Progress and Sample Processing Diagnostics.

Thanks,

Aaron.

[stereovintage]

Hi Aaron,

in the meantime, thanks for the useful and accurate information you provided me!
As you had guessed, the problem of not starting the Plots was due to the fact that i stopped the operation after about 30-45 seconds.
I noticed that on the first start the minimum time on this PC is about 55 seconds.

I also wanted to ask if there is a setting to set the x scale of the frequency in linear?

Thank you,
Fabio

[hexamer]

I am happy to announce a new release of FRA4PicoScope: https://bitbucket.org/hexamer/fra4picos ... 0_beta.msi

The primary new features are:

• Cursor/ruler and automatic measurements for FRA Plots
  • Two separate cursors can be positioned with click/drag and nudge to take arbitrary measurements
  • Delta frequency provided for measuring filter bandwidth
  • Automatic measurements for -3 dB, Gain margin, and Phase margin points
• Custom plot title and font size
• Added support for newest 6000E scopes: PS6405E, PS6425E, PS6406E, PS6426E
• Ability to run with partially installed Picotech SDK
• Allow installation to alternative location

Full details, including a list of bugs fixed, can be found here: https://bitbucket.org/hexamer/fra4picos ... %20History

Thanks a ton to several people at Pico for all their help:
Trevor (I told you for years I'd get Cursors/Rulers implemented ), Martyn, Andrew, Doug, Derek and anyone else who fielded a question behind the scenes!

And a sincere thank you to several people on the forum who reported bugs and enhancement ideas: mnni, kaimex, whichislovely, lazy_electron, Nicosten, and yosi. Many of you spent significant time and effort to document issues in great detail.