Trigger jitter with 3204

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Laszlo
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Trigger jitter with 3204

Post by Laszlo »

Hello,

I just tested my new 3204 unit it has a trigger jitter (the waveform is dancing left and right). Can it be helped?
I tried several sw versions (including latest beta), no change.
These screens show the internal generator.

Thanks,
Laszlo
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pico.zip
screen shots
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ziko
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Post by ziko »

Hi there will be a bit of jitter on the signal generator output. However this jitter will be the same for any frequency really. The signal generator is there as an additional instrument, however it is not there to completely replace a dedicated signal generator.

Kind regards
Ziko

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Laszlo
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Post by Laszlo »

Hi there,

Actually the situation is similar with other signals. I tried it with a quartz oscillator of 4MHz and the signal is jumping left and right by about 20ns around the trigger diamond. At the moment I cannot provide screenshots.

Thanks,
Laszlo

ziko
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Post by ziko »

Hi Laszlo,

Upon further investigation, this is a trigger bug. I have reported it to the software engineers.

Kind regards
Ziko

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Laszlo
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Post by Laszlo »

Hi Ziko, thank you. I hope it will be solved soon since it is pretty annoying. I thought it is not a hw problem since the ETS mode is working fine.
Kind regards, Laszlo

Robin
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Post by Robin »

Hi

Here is an updated DLL file that you can copy to your PicoScope folder. This should solve the triggering problem.

Robin
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ps3000.zip
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Laszlo
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Post by Laszlo »

Hi,

Problem is solved. Thank you for reacting this fast. You are most proficient.

Laszlo

tbbenton
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Is this problem isolated to the 3000 series?

Post by tbbenton »

Robin wrote:Hi

Here is an updated DLL file that you can copy to your PicoScope folder. This should solve the triggering problem.

Robin
I see triggering "jitter" on my 2203 with PicoScope 6.2.2.2 and I wonder if this could be the same problem. I imagine that the 3000.dll will not help 2000 series installations.

Thanks,

Tom

Robin
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Post by Robin »

Hi

ps3000.dll will not help you. Can you post a settings file saved when you get this jitter? I will try and reproduce it.

Thanks

Robin

tbbenton
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I'll post settings tonight.

Post by tbbenton »

Robin wrote: Can you post a settings file saved when you get this jitter?
Thanks Robin,

I'll get back to the lab this evening to post the settings. In the meantime I can say that the sync issue is seen with ch A connected to the output. auto trigger, auto setup, defaults otherwise, generator running square wave anywhere up to 100 kHz. (I was using 20 kHz.) The jittering looks worse as the frequency is increased, so I think it's a fixed time amount, but I haven't measured to verify. See attached file I captured this morning.
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sync_issue.png
20 kHz, persistent mode shows jitter
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tbbenton
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settings file is attached

Post by tbbenton »

The settings file is attached. Strangely, the the web form wont allow attached files with the .pssettings extension. So I zipped it in windows.

Thanks,

Tom
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sync_issue.zip
zipped pssettings file for sync issue
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Robin
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Post by Robin »

Hi Tom

This doesn't look like a trigger issue because your persistance image shows the trace passing through the trigger point correctly. The descrepancy is with the falling edge.

Are you using the scope's signal generator? Have you tried any other signal generators?

Robin

tbbenton
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It may be the generator

Post by tbbenton »

Hi Robin,

Yes. I tried an external signal generator and the trace was steady up past 100 kHz, so your thought that it might be the generator is spot on.

Feel free to start another thread or pm me.

Thanks

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