Waveforms Logic: Narrow pulses disappear when zooming out

[soerenbnoergaard]

Hi,

I have just bought a Digital Discovery and have started using it to measure some narrow pulses (10-20 ns).

I am sampling at 200 MHz and when I zoom in to the data, all the pulses show up as expected:

However, when zooming out, the pulses start to disappear from the display:

I guess the data is getting under-sampled when the pulses are narrower than 1 pixel on the display. I believe I have heard this described as "aliasing" which also occur on some digital oscilloscopes.

In other tools and on newer oscilloscopes, data like this would be shown as a black rectangle, showing the positive and negative peak within each pixel, I guess. This would be very useful when using the screenshots for documentation as the missing pulses appear quite misleading.

Is there an option in Waveforms to get this behavior? I have tried some of the different Graphics options (speed/quality) but they do not appear to have any effect on this.

I am using Digilent Waveforms version 3.19.5.

Thanks!

[attila]

Hi @soerenbnoergaard

This should be fixed in newer software versions.
Currently the latest is the public release (WF app/Help/Check for Update) but beta versions are posted more often.

https://digilent.com/reference/software/waveforms/waveforms-3/start

 

[soerenbnoergaard]

Hi @attila

That is excellent!

After clicking "Check for Updated", I downloaded Waveforms 3.20.1, and indeed the problem has been fixed.

The traces now looks like this when zoomed out:

Thank you so much for the quick response!