Frequency Response Analyzer with Bode Plots

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hexamer
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Re: Frequency Response Analyzer with Bode Plots

Post by hexamer » Sun Jun 16, 2019 7:59 pm

Andreas_ wrote:
Fri May 31, 2019 6:50 am
Hello Aaron,

thats fine for me

thanks

Andreas
Andreas,

I've made this fix and incorporated into a new released version: https://bitbucket.org/hexamer/fra4picoscope/downloads/FRA4PicoScope%200.6.2b.msi"

Please let me know how this works out.

Thanks,

Aaron.

hexamer
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Re: Frequency Response Analyzer with Bode Plots

Post by hexamer » Sun Jun 16, 2019 8:11 pm

Hello All,

I've made a new release of the application, available here:
https://bitbucket.org/hexamer/fra4picoscope/downloads/FRA4PicoScope%200.6.2b.msi

I've you've been downloading the latest release candidates, the main update in this one is support for the PS5000D scopes against the official SDK, version 10.6.13.97. To use this release, you should have the 32 bit version of this SDK installed: https://www.picotech.com/download/software/sr/PicoSDK_32_10.6.13.97.exe

It may work with the latest PicoScope Application installed, but it's not the way I've tested it :)

As usual, since I don't have a lot of scopes to test with, I appreciate all problem reports. For that matter, all feedback is welcome :)

Jeremi
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Re: Frequency Response Analyzer with Bode Plots

Post by Jeremi » Tue Aug 13, 2019 12:07 pm

Hi Aaron,
I'm trying to work with your app using a 64bit python process, so far proving tricky. Any hints on that? Or maybe a planned release of a 64bit dll?
Thanks,
Jeremi

whichislovely
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Re: Frequency Response Analyzer with Bode Plots

Post by whichislovely » Mon Sep 30, 2019 2:59 pm

Hello!

I am trying to use PicoScope5443D with the latest version FRA4PicoScope 0.6.2b.msi. I have two problems though.

1) There is a fatal error saying
"ps5000aSetChannel( 16384, 2, 0, 0, 0, 0 );Fatal error: Failed to disable channel: 290
Status: 5443D S/N: GX150/0121 successfully initialized."

2) When I try to set start frequency to be 100.0 it outputs the following error:
"Start frequency must be >= inf Hz
Error: Invalid inputs."
which confuses me.

Thanks in advance.

philbard
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Re: Frequency Response Analyzer with Bode Plots

Post by philbard » Tue Oct 15, 2019 7:32 pm

Hi All,

Sorry for what may be a very low level question, I'm new to oscilloscopes and am considering buying a 2000 or 2200 series Pico in order to do Bode Plots on guitar pickups, as I build my own for my line of guitars. I understand that the plot capability isn't available stock on the device, but see that this forum topic deals with a software workaround for that. My question: does the current version support the low end Pico models, if not what is the least expensive device that will run it? Thanks in advance for any help... Cheers Phil

hexamer
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Re: Frequency Response Analyzer with Bode Plots

Post by hexamer » Wed Nov 06, 2019 1:00 am

philbard wrote:
Tue Oct 15, 2019 7:32 pm
Hi All,

Sorry for what may be a very low level question, I'm new to oscilloscopes and am considering buying a 2000 or 2200 series Pico in order to do Bode Plots on guitar pickups, as I build my own for my line of guitars. I understand that the plot capability isn't available stock on the device, but see that this forum topic deals with a software workaround for that. My question: does the current version support the low end Pico models, if not what is the least expensive device that will run it? Thanks in advance for any help... Cheers Phil
I can tell you that I regularly use it with PS2204A, if that helps. I also occassionally us it with a PS2408B. Between these two, Fra4PicoScope is tested with both the PS2000 and PS2000A API. While I can't guarantee that all 2000 series scopes will work, it's pretty likely they will. And, if you have trouble, I can probably help out.
Last edited by hexamer on Wed Nov 06, 2019 2:45 am, edited 1 time in total.

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Re: Frequency Response Analyzer with Bode Plots

Post by hexamer » Wed Nov 06, 2019 1:13 am

whichislovely wrote:
Mon Sep 30, 2019 2:59 pm
Hello!

I am trying to use PicoScope5443D with the latest version FRA4PicoScope 0.6.2b.msi. I have two problems though.

1) There is a fatal error saying
"ps5000aSetChannel( 16384, 2, 0, 0, 0, 0 );Fatal error: Failed to disable channel: 290
Status: 5443D S/N: GX150/0121 successfully initialized."

2) When I try to set start frequency to be 100.0 it outputs the following error:
"Start frequency must be >= inf Hz
Error: Invalid inputs."
which confuses me.

Thanks in advance.
Sorry for the slow reply.

Error 290 is described in the API manual as:
PICO_CHANNEL_DISABLED_DUE_TO_USB_POWERED
USB power not sufficient to power all channels

I have occasionally had similar issues on my PS5444A where one of my PC's USB port is unable to supply enough power even for just 2 channels (admittedly I don't always use the supplied Picotech USB cable). Any combinations of the following might help:

1) Plug the scope into to AUX DC power
2) Use the Picotech USB cable if you're not already
3) Try a different USB port on your computer
4) Try a USB 3.0 port if your computer has one

I'm not sure if the second issue is a cascade issue from the first, or something different. If you continue to get it, I can help you diagnose further.

Thanks,

Aaron.

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Re: Frequency Response Analyzer with Bode Plots

Post by hexamer » Wed Nov 06, 2019 1:16 am

Jeremi wrote:
Tue Aug 13, 2019 12:07 pm
Hi Aaron,
I'm trying to work with your app using a 64bit python process, so far proving tricky. Any hints on that? Or maybe a planned release of a 64bit dll?
Thanks,
Jeremi
I suspect that's the issue (similar reason why 64bit Excel won't work, see a few posts earlier). I certainly hope to release a 64bit version of the Dll some day, but can't predict when.

teutel
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Re: Frequency Response Analyzer with Bode Plots

Post by teutel » Tue Nov 12, 2019 9:56 am

Hi Aaron,

I have a "newbie question" regarding compatibility with Windows 10 64 bit. As there have been discussions about issues related to 64 bit systems: Does your software work on my Win 10 pro 64 bit, or do I have to build the system based on an older windows PC with a 32 bit OS?

Kind regards,
Teuvo

hexamer
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Re: Frequency Response Analyzer with Bode Plots

Post by hexamer » Tue Nov 12, 2019 3:58 pm

teutel wrote:
Tue Nov 12, 2019 9:56 am
Hi Aaron,

I have a "newbie question" regarding compatibility with Windows 10 64 bit. As there have been discussions about issues related to 64 bit systems: Does your software work on my Win 10 pro 64 bit, or do I have to build the system based on an older windows PC with a 32 bit OS?

Kind regards,
Teuvo
The standalone application runs fine on both 32-bit and 64-bit windows. The application is a 32-bit application, but 64-bit windows runs 32-bit applications. There is no compelling reason to make the application 64 bit.

The issues people are reporting are when they're using the DLL version of FRA4PicoScope and trying to interface it to other 64-bit components. Currently the DLL is only built for 32-bits. I hope to supply a 64-bit DLL some day.

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Re: Frequency Response Analyzer with Bode Plots

Post by lech226@gmail.com » Wed Nov 13, 2019 9:16 am

Hello hexamer.
I am very interested in this project and I have read it from pages 1-30, thank you for your research and development.
Personally, I often make (diy) some vacuum tube amplifier to listen to music with the frequency of 20hz-20khz for 2 speakers Left and Right.
Let me ask is with PS2204A and FRA4PicoScope can evaluate my product ?
With the scenario being for one amplifier channel: input signal (sine wave general) [img][/img]is 2Vpp into amplifier RCA and Channel A of PS2204A is connected to the amplifier Speaker output).

I look forward to your answer.
sorry if there's any confusing description
Thank you very much.
Attachments
PS2204A.png

hexamer
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Re: Frequency Response Analyzer with Bode Plots

Post by hexamer » Wed Nov 13, 2019 11:25 pm

lech226@gmail.com wrote:
Wed Nov 13, 2019 9:16 am
Hello hexamer.
I am very interested in this project and I have read it from pages 1-30, thank you for your research and development.
Personally, I often make (diy) some vacuum tube amplifier to listen to music with the frequency of 20hz-20khz for 2 speakers Left and Right.
Let me ask is with PS2204A and FRA4PicoScope can evaluate my product ?
With the scenario being for one amplifier channel: input signal (sine wave general) is 2Vpp into amplifier RCA and Channel A of PS2204A is connected to the amplifier Speaker output).

I look forward to your answer.
sorry if there's any confusing description
Thank you very much.
I'm impressed that you read all 30 pages! Here are a few thoughts for your situation:

FRA4PicoScope is compatible with PS2204A and should have plenty enough stimulus frequency range for your application.

One thing your picture does not show is what's fed into channel A. Based on the fact that you show the amplifier output fed into channel B, you should also feed the signal generator into Channel A. It really doesn't matter which channel you assign for input and output (A vs. B) because you can assign that in the application.

I don't know how many watts your amplifier/speaker is designed for, but also be aware that the PS2204A has an input voltage range of +/- 20V. If your amplifier output is greater than that, you'll want to put the output channel B scope probe in x10 attenuation mode and select the same in the application.

I also assume your amplifier inputs and outputs share a common ground - otherwise be aware of ground loops.

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Re: Frequency Response Analyzer with Bode Plots

Post by lech226@gmail.com » Thu Nov 14, 2019 3:29 am

Hi Hexamer.
Have nice day and thank you very much for your reply.
That's great to me. I would to buy 2204A one.
My amplifier just around 10W with 8R spearker load. In some case, it would be 15W-30W so I'll notice the maximum of PS2204A inputting is +/-20V.
I have one question that the process of capture the requency respone to build a graph, means that capture is sine wave is not distorted, isn't it ?
Sorry if there's any confusing description
Thank you very much.

hexamer
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Re: Frequency Response Analyzer with Bode Plots

Post by hexamer » Fri Nov 15, 2019 12:29 am

lech226@gmail.com wrote:
Thu Nov 14, 2019 3:29 am
Hi Hexamer.
Have nice day and thank you very much for your reply.
That's great to me. I would to buy 2204A one.
My amplifier just around 10W with 8R spearker load. In some case, it would be 15W-30W so I'll notice the maximum of PS2204A inputting is +/-20V.
I have one question that the process of capture the requency respone to build a graph, means that capture is sine wave is not distorted, isn't it ?
Sorry if there's any confusing description
Thank you very much.

Can you help me understand what you mean by "distorted"?

The overall process works like this:

1) The application instructs the signal generator to generate a sine wave at single frequency.
2) Then a capture is simultaneously made on both the input channel and output channel.
3) Each of those captures is processed by a DFT, tuned to select the stimulus frequency.
4) The output of each DFT is a complex number describing the amplitude and phase measured.
5) The amplitude response is the amplitude of the output divided by the amplitude of the input
6) The phase response is the phase of the output minus the phase of the input
7) Repeat the process for the next frequency
8) Plot the magnitude and phase responses vs frequency

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Re: Frequency Response Analyzer with Bode Plots

Post by lech226@gmail.com » Fri Nov 15, 2019 1:52 am

Hi hexamer.
Thanks for your reply.
I mean. for example:
- Input 1Vpp 1khz -> Vacuum tube amplifier -> 8Vpp output with perfect Sine Wave -> Capture
- Input 1Vpp 15khz -> Vacuum tube amplifier -> 8Vpp output with Sine Wave was cut off the head (not perfect Sine wave output) -> Capture

in the both case, 8Vpp Output capture but the second one is Distortion.

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